Hurricane Re-Analysis Project

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Ptarmigan
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Hurricane Re-Analysis Project
http://www.aoml.noaa.gov/hrd/data_sub/re_anal.html

They have not done 1931 to 1943, which would be interesting. I know the 1932 Freeport Hurricane was rather small.

I looked at the Re-Analysis and noticed some interesting things.
1886 Indianola Hurricane radius of maximum wind (RMW) of 15 nautical miles (nm).
1900 Galveston Hurricane had RMW of 14 nm.
There is no radius of closed isobar (ROCI) for them.

1915 Galveston Hurricane had RMW of 25 nm and was quite large with ROCI of 325 nm.
1919 Florida/Texas Hurricane had RMW of 35 nm and ROCI of 250 nm.
1945 Texas Hurricane had RMW of 20 nm and ROCI of 150 nm. A rather small storm.
1949 Texas Hurricane had RMW of 15 nm and ROCI of 200 nm.

Andrew had RMW of 15 nm and ROCI of 125 from Best Track and closest to landfall.
Katrina had RMW of 20 nm and ROCI of 300 nm from Best Track and closest to landfall.
Ike had RMW of 30 nm and ROCI of 325 nm from Best Track and closest to landfall.

ftp://rammftp.cira.colostate.edu/demari ... k_atlc.txt
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Ptarmigan
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1931-1935 Re-Analysis
1931: http://www.aoml.noaa.gov/hrd/hurdat/metadata_1931.html
1932: http://www.aoml.noaa.gov/hrd/hurdat/metadata_1932.html
1933: http://www.aoml.noaa.gov/hrd/hurdat/metadata_1933.html
1934: http://www.aoml.noaa.gov/hrd/hurdat/metadata_1933.html
1935: http://www.aoml.noaa.gov/hrd/hurdat/metadata_1935.html

1933 gains two storms, loses two storms, and two storms combined. So, there is only 20 storms in 1933. I expected more, in the neighbor of 24 to 28. The Freeport 1932 Hurricane is a Category 4 with 150 mph winds at landfall and made landfall at 10 PM CST. It is likely Houston did feel major hurricane force winds.

#/Date Time Lat Lon Max Saffir RMW Central States
Wind Simpson Pressure Affected
8/14/1932 0400Z 29.0N 95.2W 130kt 4 10nmi 935mb CTX4,BTX1


The 1932 Hurricane was quite small with radius of maximum wind of 10 nautical miles.
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Ptarmigan
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I think some hurricanes of 1960s will lose their Category 5 status.
Ethel-Not likely a Category 5 due to central pressure. At most, was a Category 2 hurricane.

Carla-The central pressure with 175 mph winds is 936 millibars, while at landfall it was 931 millibars with 150 mph winds. Carla was a large hurricane, so the wind speed had to be lower.

Here is a surface wind analysis for Carla when it had central pressure of 936 millibar. It shows that Carla's peak at the time was 105 mph or Category 2. It is a large hurricane that time.
ftp://ftp.aoml.noaa.gov/hrd/pub/hwind/O ... tour08.png
ftp://ftp.aoml.noaa.gov/hrd/pub/hwind/O ... tour08.png

Donna (1960), Hattie (1961), and Beulah (1967) I expect will still be Category 5. Hattie I think is stronger than what was recorded.
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Reanalysis of Ten U.S. Landfalling Hurricanes
http://www.aoml.noaa.gov/hrd/hurdat/10_ ... icanes.pdf

Thr 1934 Louisiana Hurricane is Category 2 at landfall.

The 1938 New England Hurricane is updated as Category 3 at landfall on New York and Connecticut. It was a full blown major hurricane at landfall.

The 1944 Great Atlantic Hurricane is updated to Category 3 at landfall for North Carolina; Category 2 at landfall on New York and Rhode Island.

The 1945 Texas Hurricane is downgraded to Category 2 at peak and landfall.

The 1947 Fort Lauderdale Hurricane is downgraded from 135 knots to 115 knots, which is still Category 4. At Louisiana landfall. it is Category 2 with 95 knot winds. It makes a landfall in Louisiana considered worst case scenario for New Orleans area. If Katrina made landfall in the same way as the 1947 hurricane did, it would be really devastating.

Hurricane Carol (1954) is upgraded to Category 2 on North Carolina and Category 3 on New York.

Hurricane Edna (1954) is upgraded to Category 3 (110 knots) on North Carolina and Category 3 for Massachusetts.

Hurricane Hazel (1954) us upgraded to Category 3 on South Carolina and North Carolina.

Hurricane Donna (1960) is downgraded at peak of Category 4. No change for Florida and North Carolina. Slight downgrading for New York from 90 to 85 knots, which is Category 2.

Hurricane Gloria (1985) is upgraded for North Carolina landfall from 90 to 95 knots. No change for New York.
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Hurricane #2 (1941) was re-analyzed and shown to be a Category 3 hurricane at landfall. It peaked as a Category 3 with 125 mph winds with central pressure of 942 millibars. It was probably lower. It was also quite a large storm radius of maximum winds of 20 nautical miles or 23 miles. Just a week earlier, Tropical Storm #1 made landfall on the Upper Texas Coast. How often do you have two tropical cyclones hitting the same region within a week?
http://www.aoml.noaa.gov/hrd/hurdat/metadata_1941.html

Code: Select all

1941 Storm 2

31550 09/16/1941 M=10  2 SNBR= 696 NOT NAMED   XING=1 SSS=3                     
31550 09/17/1941 M=11  2 SNBR= 696 NOT NAMED   XING=1 SSS=3
         **        **

The 16th is removed from HURDAT
31555 09/16*  0   0   0    0*  0   0   0    0*257 836  35    0*255 845  35    0*

31560 09/17*252 854  35    0*250 863  35    0*247 871  40    0*246 880  45    0*
31560 09/17*  0   0   0    0*  0   0   0    0*237 880  25    0*246 885  30    0*
            *** ***  **      ***      **      *** ***  **          ***  **

31565 09/18*248 889  50    0*254 895  60    0*259 896  65    0*260 893  70    0*
31565 09/18*253 890  30    0*257 895  35    0*259 896  35    0*260 893  40    0*
            *** ***  **      ***      **               **               **

31570 09/19*260 889  70    0*258 886  75    0*256 883  75    0*253 881  75    0*
31570 09/19*260 890  45    0*258 888  50    0*255 886  55    0*252 885  55    0*
                ***  **          ***  **      *** ***  **      *** ***  **

31575 09/20*249 880  80    0*245 878  80    0*241 876  80    0*234 876  80    0*
31575 09/20*248 884  55    0*245 882  60    0*241 880  60    0*236 877  60    0*
            *** ***  **          ***  **          ***  **      *** ***  **

31580 09/21*230 882  80    0*234 887  80    0*240 892  80    0*244 896  80    0*
31580 09/21*233 879  60    0*238 882  65    0*244 887  70    0*248 893  70    0*
            *** ***  **      *** ***  **      *** ***  **      *** ***  **

31585 09/22*249 900  80    0*254 907  75    0*259 916  75    0*263 926  75    0*
31585 09/22*251 901  75    0*254 909  80    0*259 919  85    0*263 929  90    0*
            *** ***  **          ***  **          ***  **          ***  **

31590 09/23*266 937  75    0*271 946  70    0*277 953  70    0*283 955  70    0*
31590 09/23*267 939  95    0*272 948 100    0*277 953 105    0*283 955 110    0*
            *** ***  **      *** *** ***              ***              ***

31595 09/24*290 955  60  977*298 954  55    0*316 947  45    0E343 927  35    0*
31595 09/24*290 956  85    0*298 956  65    0*315 949  40    0*335 932  35    0*
                ***  **          ***  **      *** ***  **     **** ***  

31600 09/25E369 909  35    0E395 882  35    0E422 855  30    0E445 828  30    0*
31600 09/25*360 911  35  989E388 887  35  988E424 859  40  985E449 826  50    0*
           **** ***      *** *** ***      *** *** ***  **  *** *** ***  **

The 26th and 27th are new to HURDAT
31602 09/26E476 789  55    0E503 747  50    0E530 705  45    0E556 675  45    0*
31603 09/27E582 660  45    0*  0   0   0    0*  0   0   0    0*  0   0   0    0*

31605 HRCTX3
31605 HRCTX3BTX2
            ****

U.S. Landfall: 9/23/1941 - 22Z - 28.8N, 95.6W - 100 kt - 958 mb - 1007 mb OCI 
- 250 nm ROCI - 20 nm RMW

Minor track changes and major intensity changes are analyzed for this 
hurricane that made landfall in Texas.  A major alteration is made with 
genesis, delayed for a day.  A major change is also made to the timing of 
dissipation, delayed for a day.  Evidence for these alterations comes from 
the Historical Weather Maps Series, the COADS ship database, Monthly Weather 
Review, USWB/NHC microfilm of synoptic weather maps, Original Monthly Records 
from NCDC, monthly climatological data summaries from NCDC, U.S. Weather 
Bureau operational advisories, Dunn and Miller (1960), Ellis (1988), Schwerdt 
et al. (1979), Ho et al. (1987), Jarrell et al. (1992) and Connor (1956).

September 16: HWM indicates a spot low near 24N, 86W. HURDAT lists this as a 
Tropical storm with 35kt winds at 25.7N, 83.6W at 12Z. Ship highlights: No 
gales or low pressures. Station highlights: No gales or low pressures.

September 17: HWM indicates a closed low with a pressure of at most 1010mb 
near 25N, 86W. HURDAT lists this as a Tropical storm with 40kt winds at 
24.7N, 87.1W at 12Z. Ship highlights: No gales or low pressures. Station 
highlights: No gales or low pressures. 

September 18: HWM indicates a Tropical Storm with a pressure of at most 
1005mb near 24.9N, 89.5W. HURDAT lists this as a Category 1 Hurricane with 
65kt winds at 25.9N, 89.6W at 12Z. The MWR Tracks of lows showed a center at 
25.5N, 89W (am) with a pressure of 1006mb. Ship highlights: No gales or low 
pressures. Station highlights: No gales or low pressures. "This hurricane was 
first noted as a disturbance of slight intensity about 180 miles south of 
Port Eads, La., on September 18. For 48 hours the center drifted gradually 
southward toward the Yucatan coast with winds increasing to gale force" 
(MWR).  "Date...Sept. 18-26.  Place where first reported...About 180 miles south 
of Port Eads, La" (MWR).

September 19: HWM indicates a Hurricane with a pressure of at most 1000mb 
near 25N, 88.9N. HURDAT lists this as a Category 1 Hurricane with 75kt winds 
at 25.6N, 88.3W at 12Z. The MWR Tracks of lows showed a center at 25N, 88W 
(am) with a pressure of 1003mb. Microfilm at 12Z analyzes a closed low of at 
mosr 999 mb centered near 25.5N, 89.0W. Ship highlights: 40kt SE with a 
pressure of 1003mb at 25.5N, 88W at 1230Z (USWB); 40 kt SE with 1000 mb at 
1830Z at 26.0N, 89.0W (USWB). Station highlights: No gales and low pressures. 

September 20: HWM indicates a Hurricane with a pressure of at most 1000mb 
near 24N, 88.3W. HURDAT lists this as a Category 1 Hurricane with 80kt winds 
at 24.1N, 87.6W at 12Z. The MWR Tracks of lows showed a center at 24.5N, 
88.5W (am) and at 23N, 88W (pm).  Microfilm at 12Z analyzes a closed low of 
at most 1002 mb centered near 23.9N, 88.4W. Ship highlights: 35kt ENE with a 
pressure of 1002mb at 24.9N, 87.7W at 20Z with a max wind of 50 kt E (MWR). 
Station highlights: No gales or low pressures. "During the night of September 
20-21 the storm turned, and moving northward retraced its path until, on the 
evening observation of the 21st, it was again near the regions where first 
detected" (MWR).

September 21: HWM indicates a Hurricane with a pressure of at most 990mb near 
24N, 89W. HURDAT lists this as a Category 1 Hurricane with 80kt winds at 24N, 
89.2W at 12Z. The MWR Tracks of lows showed a center at 23N, 90W (am) and at 
24N, 91W (pm). Microfilm at 12Z analyzes a closed low of at most 1002 mb 
centered in the general vicinity of 23.8N, 88.9W.  Ship highlights: 993 mb at 
09Z at 24.2N, 88.4W and 70kt at or near 09Z at or near 24.2N, 88.4W (USWB); 
45kt E with a pressure of 999mb at 25.3N, 87W at 1230Z (USWB). Station 
highlights: No gales or low pressures.  "Eastern Sun - (24.15-88.25) 4am - 
passed through center of storm - force 12 (no directions given) - barometer 
29.32 ([9]92[.]9mb)" (USWB).

September 22: HWM indicates a Hurricane with a pressure of at most 990mb near 
25.5N, 92W. HURDAT lists this as a Category 1 Hurricane with 75kt winds at 
25.9N, 91.6W at 12Z. The MWR Tracks of lows showed a center at 25N, 92W (am) 
and at 26N, 94W (pm).  Microfilm at 12Z analyzes a closed low of at most 993 
mb centered near 26.1N, 91.9W. Ship highlights: 30 kt NW with 991 mb at 21Z 
at 26.8N, 94.1W (MWR); 55kt W with a pressure of 999mb at 26.6N, 94.5W (no 
time given) (USWB); 70 kt NE before 2359Z in the vicinity of 27.1N, 93.7W 
(MWR). Station highlights: 22 kt NE with 1005 mb at 22Z at Corpus Christi NAS 
(27.7N, 97.3W) (OMR); 37 kt NE around ~2330Z at Port Arthur (29.9N, 93.9W) 
(OMR). "A ship near 27°06' N, 93°42' W, on September 22 reported a northeast 
wind, force 12, and a low barometer reading of 985.8mb. On the coast, Texas 
City reported the highest recorded wind velocity, 83 miles per hour. 
Estimated winds up to 100 miles per hour came from several points nearer the 
storm center" (MWR). 

September 23: HWM indicates a Hurricane with a pressure of at most 985mb near 
27.1N, 95.3W. HURDAT lists this as a Category 1 Hurricane with 70kt winds at 
27.7N, 95.3W at 12Z. The MWR Tracks of lows showed a center at 28N, 95.5W 
(am) with a pressure of 985mb and at 29N, 95W (pm).  Microfilm at 12Z 
analyzes a closed low of at most 987 mb centered near 27.4N, 95.3W.  Ship 
highlights: 40 kt E with a pressure of 986mb at 27.1N, 93.7W at 00Z (MWR, 
USWB); 20kt WSW with a pressure of 986mb at 26.7N, 94.6W at 01Z (USWB); 70kt 
S with a pressure of 1000mb at 28.7N, 94W at 18Z (MWR). Station highlights: 
42 kt SE around ~1930Z at Galveston (OMR); 52 kt at Port Aransas (27.8N, 
97.1W) (Connor); 991 mb at Port Lavaca (28.6N, 96.6W) at 22Z (Connor); 977 mb 
at Matagorda (28.7N, 96.0W) at 2225Z (USWB). "It then took a northwestward 
course through the western Gulf of Mexico and moved inland on the Texas coast 
near Matagorda at 3:25pm (CST) on September 23" (MWR). "Recurving to the 
northeastward after crossing the Texas coast the storm center passed slightly 
west of Houston. The lowest pressure registered along the path of the 
hurricane, 970.5mb, was observed at Houston Airport at 11:08pm of the 23rd. 
The passage of the low pressure was accompanied by winds estimated at 75 
miles per hour; a recorded velocity becoming impossible because of power 
failure" (MWR).  "Tropical cyclones in Texas, Sept. 23, Matagorda, Minimal, 4 
killed, damage $6,000,000" (minimal is equivalent to winds of 74-100 mph and 
central pressure 983-996 mb - Dunn and Miller).  "Sept. 23 - Hurricane made 
landfall near Freeport with 90 mph winds, tide of 9.9', and barometer 28.31 
[958.7 mb].  Extremely high tides were reported along the entire coast from 
Matagorda to Galveston.  Four lives were lost, and property damage was 
estimated at $6.5 million" (Ellis).  "Sept. 23 - 1011 mb environmental 
pressure, 93 kt max sustained winds at landfall" (Schwerdt et al.).  "Sept. 
23 - 959 mb central pressure, 970 mb pressure at Houston, 21 nm RMW, 13 kt 
[speed] at landfall, landfall 28.8N, 95.6W" (Ho et. al).  "1941, Sep, TX 3N, 
958 mb central pressure" (Jarrell et al.).  "Sep. 23 - Center crossed coast 
near Matagorda.  Pressures: Houston 28.66" [971 mb], Galveston 29.26" [991 
mb], AOE 29.25" [991 mb], ship at 27N 97.3W 29.11" [986 mb], Port Aransas 
29.41" [996 mb], Corpus Christi 29.47" [998 mb], Port Lavaca 29.25" [991 mb].  
Estimated lowest 28.30" [958 mb].  Winds: Houston 75 mph [65 kt], Texas City 
83 mph [72 kt], ship 27N, 93.7W 75 mph [65 kt], NAS Corpus Christi NNW 58 mph 
[50 kt], Port Aransas 60 mph [52 kt], PAH SE 73 mph [63 kt], Grand Isle E 35-
40 mph [30-35 kt].  Tides: Matagorda 10.8 ft, Galveston 7.0 ft, Sargent 9.9 
ft, Port O'Connor 5.9 ft, Aransas Game Refuge 5.0 ft, Shell Island Reef 6.5 
ft, Frenier 5.6 ft, Cameron 5 ft, Sabine 5.7 ft, Anahuac 7.0 ft, LaPorte 8.0 
ft, Texas City 7.5 ft, Freeport 10.6 ft, Port La Vaca 6.4 ft, Ft. Point 5.6 
ft" (Connor).  "Maximum wind velocity reported...Force 12 NE., a ship, 83 miles 
per hour, Texas City, Tex.  Lowest barometer reported...970.5 mb, a ship.  
Coast lines crossed...Texas.  Place of dissipation...Southern Quebec Province.  
Intensity...Full hurricane.  Remarks...4 lives lost; $2,000,000 property damage; 
crop losses estimated in excess of $5,000,000" (MWR).  

September 24: HWM indicates a closed low with a pressure of at most 990mb 
near 31.8N, 94.5W. HURDAT lists this as a Tropical storm with 45kt winds at 
31.6N, 94.7W at 12Z. The MWR Tracks of lows showed a center at 32N, 94W (am) 
with a pressure of 982.4mb and at 36N, 92W (pm). Microfilm at 12Z analyzes a 
closed low of at most 990 mb centered near 31.6N, 95.0W. Ship highlights: 
35kt SW with a pressure of 1001mb at 28.8n, 94W at 1230Z (USWB). Station 
highlights: 988 mb (min p) at Galveston Airport and 991 mb (min p) at 
Galveston WBO (29.3N, 94.8W) both at 04Z (OMR); 53 kt S (max w/1-min/35m) at 
Galveston at 0420Z (OMR); 72kt at Texas City (29.4N, 94.9W) likely around 
~04Z (MWR); 63 kt at Ellington Field (29.6N, 95.2W) (WB advisories); 52 kt E 
(max w/5-min/58 m) at ~0430Z and 970 mb (min p) at 0508Z at Houston (29.8N, 
95.4W) (MWR/OMR); 973 mb (min p) at 0510Z at Richmond (29.6N, 95.8W) 
(Connor); 975 mb at 0530Z at Alvin (29.6N, 95.3W) (Connor); 63 kt SE (fastest 
mile/41m) around ~0530Z and 996 mb (min p) at 0820Z at Port Arthur (OMR); 39 
kt S ( 5-min/41m) at Port Arthur around ~1130Z (OMR); 35 kt SE (max w/5-
min/69m) around ~1530Z and 990 mb (min p) at 1615Z at Shreveport (32.5N, 
93.8W) (OMR); 18 kt S with 992 mb at 1830Z at Shreveport; 991 mb (min p) at 
Little Rock, AR (34.7N, 92.3W) likely around 22Z or 23Z (climo). "The 
following excerpts from a report by G. P. Rusmisel, of the Galveston office, 
relate to conditions at that station during the approach and passage of the 
storm: By late afternoon of the 22nd the sky became completely overcast with 
low clouds of bad weather which predominated throughout the remainder of the 
storm. Tides became to rise on the 21st and more rapidly to a crest of 6.7 
feet at 8pm and 10pm CST on the 22nd, then falling to 5 feet at 1 pm of the 
23rd. Tides rose again thereafter to a crest of 7 feet at 9 and 10pm CST on 
the 23rd, after which they subsided rapidly. The sea was rather light at about 
10 swells per minute until the storm moved toward the Texas coast, after 
which an increase set in becoming very heavy and reaching 5 swells per minute 
at the height of the storm. Tidewater covered all of the Galveston Island 
beaches, much of the island beyond the seawall, and entered the lower 
residential and business sections as backwater from the bay. Tidewater also 
covered the municipal airport to a depth of approximately 1 to 3 ft and was 
about 6 inches deep on the floor of the airport administration building and 
in the C. A. A. communications station room, putting that office out of 
commission until after the water receded and power and telephone service was 
restored the evening of the 25th" (MWR). 

September 25: HWM indicates a closed low with a pressure of at most 990mb 
centered just SW of Grand Rapids, MI near 43N, 86W with fronts running 
through the low. HURDAT lists this as an Extratropical cyclone with 30kt 
winds at 42.2N, 85.5W at 12Z. The MWR Tracks of lows showed a center at 
42.5N, 86W (am) with a pressure of 987.3mb and a center at 48N 77W (pm). 
Microfilm at 12Z analyzes a closed low of at most 987 mb near the HWM 
position with fronts analyzed attached to the low.  Ship highlights: No gales 
or low pressures. Station highlights: 15 kt W with 993 mb at 0030Z at Little 
Rock, AR (USWB); 36 kt SW (max w) at Evansville, IN likely around ~12Z (MWR); 
986 mb (min p) at Grand Rapids, MI likely around ~13Z (MWR); 44 kt W (max w) 
at Fort Wayne, IN likely around ~14Z (MWR); 15 kt NW with 986 mb at 1830Z at 
Alpena, MI (USWB); 56 kt SW (max w) at Buffalo, NY likely around ~20Z [but 49 
kt max w after converting to 10m 1-min] (MWR).  "Progressive movement of the 
storm increased rapidly as the center moved up the Mississippi Valley and 
passed over the Canadian boundary in the Lake region. Available sources 
estimate property damage at well over $2,000,000. The rice crop in the region 
affected was ruined, and has been estimated as a loss of $4,000,000. About 25 
to 30 percent of the cotton crop had been picked in this section. Half of 
that remaining in the fields has been reported lost. It is noteworthy that, 
so far as is known, only four lives were lost, either directly or indirectly, 
as a result of this storm which traversed a low-lying region where without 
warning thousands would have been left to the mercy of wind and tide" (MWR). 

September 26: HWM analyzes a tropical storm of at most 985 mb centered near 
53N, 63.5W with fronts running through the cyclone.  HURDAT no longer lists a 
system on this day.  The MWR tracks of lows shows a position near 53N, 70.2W 
(am) and a position near 58N 66W (pm).  Station highlights: 30 kt W with 1004 
mb at Buffalo, NY at 0030Z (USWB); 25 kt W with 1002 mb at Toronto, Canada at 
0030Z (USWB); 15 kt SSE with 997 mb at Montreal, Canada at 0030Z (USWB); 15 
kt S with 1000 mb at Caribou, ME at 0630Z (USWB); 30 kt SW with 996 mb at 12Z 
at 48.4N, 68.6W (HWM); ~20 kt SE with 994 mb at 12Z at 53.7N, 57.1W (HWM).

September 27: HWM analyzes a closed low of at most 975 mb centered near 65N, 
60.5W with an occluded front extending from near the low southeastward to a 
triple point near 60N, 49W.  HURDAT did not previously list a system on this 
day.  The MWR tracks of low shows a final position near 63N, 65W with a 988 
mb pressure (am).  Station highlights: 40 kt NW with 986 mb at 12Z at 61.4N, 
64.9W (HWM).

A tropical wave or trough slowly began to form into a more concentrated area 
of low pressure on 15-16 September near the western tip of Cuba moving slowly 
north-northwestward.  Good observational coverage on the 16th and early on the 
17th indicates that a well-defined, closed circulation was not yet present.  
HURDAT originally began the cyclone at 12Z on the 16th in the eastern Gulf of 
Mexico.  Observations from the microfilm map at 12Z on the 17th indicate a 
possibility that the low might have been closed by then.  Therefore, genesis 
is now shown at 12Z on the 17th (24 hours later than originally) in the 
central Gulf.  Sufficient observational coverage provides evidence that the 
intensity was only a tropical depression at 12Z the 17th and the 00Z the 18th 
microfilm maps.  Data on the 18th at 00Z suggests a central pressure of at 
most 1008 mb which yields of wind speed of at least 30 and 28 kt, 
respectively, according to the Brown et al. (2006) southern and north of 25N 
pressure-wind relationships.  A 30 kt intensity is selected for 00Z on the 
18th (down from 50 kt originally - a major change).  Although the first low 
pressure was not observed until 00Z on the 19th with the first 35 kt gale 
observed at 06Z the 19th, the cyclone is analyzed to have become a tropical 
storm at 06Z on the 18th (36 hours later than originally - a major change) 
because of the slightly sparser data coverage near the center of the 18th.  
For the track, the cyclone meandered slowly from the 18th - 21st in the south-
central Gulf of Mexico making a small clockwise loop on the 18th and 19th.  It 
was at 26N, 89W on the 19th at 00Z, and then it moved south to 23.3N, 87.9W by 
the 21st at 00Z.  From that point, it moved west-northwestward toward the 
Texas coast, where it made landfall late on the 23rd.  The largest track 
change for the entire existing portion of the track (17th-25th) is less than 1 
degree.  For the intensity in the Gulf of Mexico, major downward intensity 
adjustments of 20 to 30 kt are analyzed at all times from 00Z on the 18th - 
00Z on the 21st.  On the 19th at 00Z, a 1005 mb peripheral pressure suggests 
winds of greater than 37 and 34 kt for south and north of 25N, respectively; 
45 kt is analyzed (down from 70 kt originally).  At 12Z on the 19th, a 40 kt 
wind was observed.  Also at 12Z, a peripheral pressure of 1000 mb suggests 
winds greater than 47 and 44 kt for south and north of 25N.  This ship - 
which also measured 35 kt E - was about 30 nm northwest of the cyclone.  A 
second ship that observed 40 kt SE with 1003 mb at the same time was about 40 
nm east of the cyclone.  These observations are not consistent with a 75 kt 
hurricane as originally shown in HURDAT, but are consistent with around a 55 
kt tropical storm.  On the 21st, a 993 mb pressure was recorded around 09Z.  
It is uncertain whether this was a central pressure measurement.  The first 
hurricane force wind from a ship also occurred on the 21st sometime around 09Z 
(it is unclear whether the "force 12" report occurred at the same time as the 
993 mb pressure).  The cyclone is analyzed to have reached hurricane 
intensity at 06Z on the 21st (66 hours later than originally - a major 
change), based upon interpolation from the 55 kt at 12Z on the 19th and 
subsequent landfall as a 100 kt major hurricane two days later.  This is 
consistent with the available (but ambiguous) observations on the 21st.  On 
the 23rd at 00Z, with the cyclone 22 hours away from making landfall in Texas, 
a 986 mb peripheral pressure was recorded, suggesting winds of greater than 
65 kt according to the north of 25N pressure-wind relationship.

The hurricane made landfall on the Texas coast between Matagorda Bay and 
Freeport at 28.8N, 95.6W on 23 September at 22Z.  The landfall point is also 
the recurvature point of this hurricane (95.6W was the farthest west the 
cyclone reached).  The city of Matagorda (28.7N, 96.0W) recorded a pressure 
of 977 mb at either 2125Z or 2225Z but there is no wind data available for 
Matagorda so it is uncertain whether the RMW was experienced there.  Ho et 
al. lists a landfall RMW of 21 nm, and Matagorda was located about 25 nm west 
of the analyzed center at closest approach.  A run of the Schloemer equation 
utilizing the assumption that Matagorda was located about 5 nm outside of the 
RMW yields a central pressure of 953 mb, while assuming that Matagorda was 
about 10 nm outside of the RMW (with an RMW of 15 nm) yields 939 mb.  Seven 
hours after landfall, Houston recorded a 970 mb pressure at 0508Z on the 24th.  
Wind data from Houston indicates that the center passed about 20 nm west of 
the station and that the 970 mb value was not a central pressure and likely 
not inside the RMW, as no lull occurred at the time of the lowest pressure.  
(This is not certain, however, as the wind record from Houston is provided in 
hourly averages with peak 5 min winds to have occurred within the hour.  A 
lull that lasted less than an hour could have occurred but not recorded.)  
Runs of the Schloemer equation indicate a central pressure at that time 
(seven hours after landfall) of 948 mb assuming that Houston was at the RMW. 
(The 948 mb calculation is independent of the RMW size when the RMW equals 
the radius from the center of the pressure measurement in the equation).  If 
the central pressure was indeed that low several hours after landfall, the 
landfall central pressure would have been significantly lower.  Ho et al.'s 
inland pressure decay model for the Gulf coast would suggest a value close to 
900 mb at landfall and even a value of 935 mb by using the Florida decay 
model (which fills slower and may be somewhat reasonable to use given that 
the hurricane would have been paralleling Galveston Bay somewhat).  
Therefore, somewhat conservatively, a 942 mb central pressure is chosen for 
landfall.  A 942 mb central pressure equals 113 kt according to the Brown et 
al. north of 25N pressure-wind relationship and 118 kt for its intensifying 
subset.  Climatological RMW for this central pressure and landfall latitude 
is 17 nm, so this system is close to average assuming an RMW of 20 nm.  The 
outer closed isobar of 1007 mb is substantially lower than usual with a 
rather large radius of 250 nm, while the hurricane was moving at a near 
average 12 kt.  Thus a 110 kt intensity is selected for landfall (somewhat 
below the pressure-wind relationship), maintaining this as a high end 
Category 3 for north Texas.  The highest observed winds were 78 kt at 
Freeport and 72 kt at Texas City.  Major upward intensity adjustments of 20-
40 kt are implemented from 00Z on the 23rd - 00Z on the 24th.  A peak lifetime 
intensity of 110 kt is analyzed at 18Z on the 23rd through the 22Z landfall 
(original peak was 80 kt from 00Z/20th - 00Z/22nd).  A run of the parametric 
wind model suggests that 92 kt winds occurred on the coast at the border of 
Central Texas and North Texas (28.6N, 96.0W), which is very near where the 
left edge of the RMW passed.  Therefore, a Category 2 impact is added to 
HURDAT for Central Texas.  Runs of the Kaplan and DeMaria inland decay model 
yield 85, 63, 42 and 28 kt for 00, 06, 12 and 18Z on the 24th.  Highest 
observed winds within 2 hr of synoptic times are: 78 kt at 00Z, 72 kt at 06Z, 
37 kt at 12Z and 32 kt at 18Z.  Analyzed intensities are 85, 65, 40, and 35 
kt (originally 60, 55, 45, and 35 kt).  The center moved northeastward 
through northwestern Louisiana and Arkansas between 12Z on the 24th - 00Z on 
the 25th and it was accelerating.  The cyclone is analyzed to have become 
extratropical at 06Z on the 25th centered over southern Illinois.  A 35 kt is 
analyzed from 18Z on the 24th through 06Z on the 25th.  This cyclone produced 
tropical storm impacts in Louisiana and Arkansas.  Tropical storm impacts are 
not analyzed for Mississippi, Tennessee, Kentucky, Missouri, or Illinois 
because the strongest winds, located a short distance SSE of the center, were 
not experienced in any of those states while the system was still tropical.  
Maximum winds observed after converting to 10m 1-min were: 32 kt at 
Shreveport, 30 kt at Little Rock, 29 kt at Memphis, and 25 kt at Cairo, IL.  
After that, the cyclone reintensified as an extratropical system.  Damaging 
winds occurred across portions of the Upper Midwest and into western New 
York.  On the 25th, the following central pressure values are analyzed and 
added to HURDAT: 989, 988 and 985 mb at 00, 06 and 12Z.  A 986 mb pressure 
was recorded at Grand Rapids, MI.  After converting to 10m 1-min, the 
following winds were recorded on the 25th: 40 kt at Detroit; 44 kt at Fort 
Wayne, IN around 14Z; 42 kt at Dayton, OH; and 49 kt at Buffalo, NY around 
20Z.  The cyclone is analyzed to have reintensified to 50 kt by 18Z on the 
25th when the center was over Lake Huron reaching a peak of 55 kt at 00Z on 
the 26th.  HURDAT originally showed dissipation after 18Z on the 25th.  
Dissipation is delayed by 30 hours until after 00Z on the 27th - a major 
change, as the analyses from HWM indicate that the system continued moving 
northeastward.  This assessment is also consistent with the MWR Tracks of 
Lows analysis through 00Z on the 27th.  The final point at 00Z on the 27th is 
58.2N, 66.0W as a 45 kt extratropical cyclone as the cyclone was absorbed by 
a larger extratropical system after that time.  
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Ptarmigan
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A year later, another major hurricane makes landfall on Upper Texas Coast, Hurricane #3 or Matagorda Hurricane. Like 1941, two tropical cyclones made landfall on the Upper Texas Coast weeks earlier, in this case about 2 weeks earlier with Hurricane #2. Could we see a season where two tropical systems make landfall just weeks apart on the Upper Texas Coast? Yes, just look at 1941 and 1942.
http://www.aoml.noaa.gov/hrd/hurdat/metadata_1942.html

Code: Select all

U.S. Hurricane:
Aug 30th - 09Z - 28.3N 96.6W - 100 kt - Category 3 - 950 mb - 1007 mb 
OCI - 250 nm ROCI

Major track and intensity changes are analyzed for this hurricane that 
made landfall in the central Texas coast.  Additionally, a major 
alteration is to remove the first two days.  Also, one additional day 
is added at the end of the cyclone's lifetime.  Evidence for these 
alterations comes from the Historical Weather Maps Series, the COADS 
ship database, Monthly Weather Review, USWB/NHC microfilm of synoptic 
weather maps, the Original Monthly Records from NCDC, the Mexican 
synoptic maps, Texas Climatological Data, Connor (1956), Ho et al. 
(1987), and Jarrell et al. (1992).

Storm 3 (Old Storm 2)

August 20: HWM indicates a spot low near 12.5N, 59.5W. Ship 
highlights: No gales or low pressures. Station highlights: No gales or 
low pressures. 

August 21: HWM indicates a closed low with a pressure of at most 
1010mb near 14N, 60W. HURDAT lists this as a Tropical Storm with 35kt 
winds at 13.9N, 60.8W at 12Z. Micro shows a closed low pressure of at 
most 1011mb at 12.5N, 61.5W at 12Z. Ship highlights: No gales or low 
pressures. Station highlights: No gales or low pressures. "The wave, 
from which this storm formed, passed over the Windward Islands near 
Santa Lucia on August 21, attended by heavy squalls but with no 
indications of organized circulation" (MWR). 

August 22: HWM indicates a spot low near 14N, 63.5W. HURDAT lists this 
as a Tropical Storm with 35kt winds at 14.1N, 65.4W at 12Z. Micro 
shows a closed low pressure of at most 1011mb at 13.5N, 63.5W at 12Z. 
Ship highlights: No gales or low pressures. Station highlights: No 
gales or low pressures.

August 23: HWM indicates a closed low of at most 1010mb near 16N, 76W. 
HURDAT lists this as a Tropical Storm with 40kt winds at 14.8N, 70.3W 
at 12Z. Micro does not show an organized system. Ship highlights: No 
gales or low pressures. Station highlights: No gales or low pressures. 

August 24: HWM indicates a spot low pressure near 16.5N, 79.5W. HURDAT 
lists this as a Tropical Storm with 55kt winds at 15.7N, 75W at 12Z. 
Ship highlights: No gales or low pressures. Micro shows a spot low at 
17.5N, 79.8W at 12Z. Station highlights: No gales or low pressures. 
"Moving rapidly westward through the central Caribbean Sea, the wave 
formation passed south of Jamaica during the night of the 24th, where 
its progress became slower and the first indications of development 
were noted" (MWR). "Carson from Navy - 11 pm 8/23/42. 'Ship 50-60 
miles S of SE tip Dominican Republic 1 am - Wind force 6 - pressure 
one inch below normal reading" (Micro).

August 25: HWM indicates a spot low pressure near 16N, 81.5W. HURDAT 
lists this as a Category 1 Hurricane with 75kt winds at 16.8N, 79.3W 
at 12Z. Micro shows a closed low pressure of at most 1008mb at 17.4N, 
80.6W at 12Z. Ship highlights: No gales or low pressures. Station 
highlights: No gales or low pressures. Aircraft highlights: Special 
plane report, 40-45 kt, 1000 mb at 18Z (USWB).  "Special Report from 
Navy.  Plane from Grand Caymen reports that at 2 pm - pressure was 
999.7 Mbs.  Wind 40 to 45 knots.  (From Carson by phone 11.15 pm)" 
(USWB).

August 26: HWM indicates a Tropical Storm with a pressure of at most 
1005mb near 17N, 82.5W. HURDAT lists this as a Category 2 Hurricane 
with 85kt winds at 17.9N, 81.9W at 12Z. The MWR Tracks of lows showed 
a center at 17N, 79W (am) with a pressure of 1003.4mb and at 17.5N, 
80W (pm). Micro shows a closed low pressure of at most 1008mb at 
17.5N, 82W at 12Z. Ship highlights: No gales or low pressures. Station 
highlights: No gales or low pressures. 

August 27: HWM indicates a Tropical Storm with a pressure of at most 
1000mb near 19N, 85W. HURDAT lists this as a Category 2 Hurricane with 
90kt winds at 19.4N, 84.6W at 12Z. The MWR Tracks of lows showed a 
center at 18N, 82W (am) with a pressure of 1003.4mb and at 19N, 86W 
(pm). Micro shows a closed low pressure of at most 1002mb at 18.5N, 
85W at 12Z. Ship highlights: No gales or low pressures. Station 
highlights: 15kt W with a pressure of 1003mb at Swan Islands at 0Z 
(USWB); 25kt S with pressure of 1005 mb at 6Z at Swan Islands at 06Z 
(USWB); 40kt NNE with a pressure of 1004mb at 18Z near 20.5N, 86.9W 
(USWB); 40kt NE with a pressure of 996mb at Cozumel, Mexico at 21Z 
(USWB); and 35kt NNW at Cozumel, Mexico at 22Z (USWB). "It passed 
north of Swan Island as a moderate storm but with definite indications 
of rapidly increasing intensity, and crossed the tip of Yucatan 
Peninsula during the night of August 27, attended by full hurricane 
winds" (MWR). "A moderate tropical weather disturbance to the 
southward of Jamaica, moving to westward between the 24th and 25th 
causing heavy rainfall over the Island and considerable flood damages. 
The barometric pressure fell about 0.150 inch below the normal, also 
low pressure reported at Morant Point and Negril Point Lighthouses, 
Beyond a heavy rainsquall ay Kingston and Morant Point, there was no 
very severe damage, owing to gale winds over the island" (JAMAICA).


August 28: HWM indicates a Tropical Storm with a pressure of at most 
1000mb near 23N, 89.5W. HURDAT lists this as a Category 2 Hurricane 
with 90kt winds at 22.2N, 88.8W at 12Z. The MWR Tracks of lows showed 
a center at 20.5N, 89.5W (am) with a pressure of 999.9mb and at 22N, 
91W (pm). Micro shows a closed low pressure of at most 1002mb at 
22.5N, 88.5W at 12Z. Ship highlights: No gales or low pressures. 
Station highlights: 10kt NNE with a pressure of 1002mb at Progreso at 
0Z (USWB); 989mb with 40 kt NE at Cozumel at 00Z (USWB); 10kt W with a 
pressure of 1005mb at Merida (21N, 89.8W) at 12Z (HWM); 20kt W with a 
pressure of 1004mb at Pregreso at 18Z (USWB). "Passing into the Gulf 
of Mexico, and moving northwestward in an almost straight line it 
reached the Texas coast, approximately two days later, as a large and 
severe storm attended by full hurricane winds over a path nearly 150 
miles in width" (MWR). "Evidence of this disturbance began to appear 
at Galveston the afternoon of the 28th. A bank of cirrus clouds began 
to appear on the southern horizon. The movement was slow and difficult 
to observe but appeared SSW or SW. These clouds had become at the tame 
of the 7:30pm EST observation. The Gulf of Mexico also presented 
evidence of disturbed conditions late on the 28th with the tide 
somewhat above normal and a moderately rough sea with a count of about 
8 swells per minute at the foot of 25th street." (OMR). 

August 29: HWM indicates a Tropical Storm with a pressure of at most 
995mb near 25.5N, 93W. HURDAT lists this as a Category 3 Hurricane 
with 100kt winds at 25.5N, 92.8W at 12Z. The MWR Tracks of lows showed 
a center at 23N, 93W (am) and at 25N, 95W (pm). Micro shows a closed 
low pressure of at most 1008mb at 25N, 93W at 12Z. Ship highlights: No 
gales or low pressures. Station highlights: 24kt N with a pressure of 
1004mb at Corpus Christi Naval Air Station (27.7N, 97.3W) at 21Z 
(MAR); 40kt E at Galveston (29.3N, 94.8W) no time given (OMR); 40kt 
NNE at Foster Field (28.9N, 96.9W) no time given (OMR). 


August 30: HWM indicates a closed low of at most 990mb near 29.5N, 
98W. HURDAT lists this as a Tropical Storm with 60kt winds at 29.3N, 
97W at 12Z. The MWR Tracks of lows showed a center at 27N, 97W (am) 
with a pressure of 993.2mb and at 29N, 99.9W (pm). Micro shows a 
closed low pressure of at most 990mb at 29N, 97.5W at 12Z. Ship 
highlights: No gales or low pressures. Station highlights: A fairly 
complete calm with a pressure of 952mb at Seadrift (28.4N, 96.7W) at 
0955Z (MWR); A pressure of 983mb at San Antonio (Min P) at 1615Z 
(OMR); 64kt NE (1-min wind) at San Antonio at 16Z (OMR); A pressure of 
986mb at Corpus Christi (27.8N, 97.4W) at 0830Z (OMR). 77kt ENE at 
Kelly Field (29.4N, 98.5W) no time given (OMR); 74kt NNE at Foster 
Field (28.9N, 96.9W), no time given (OMR). "The lowest barometer at 
the Galveston airport, 5 miles southwest of the city office, was 29.49 
inches at 1:30am EST on the 30th. Winds were easterly at Galveston on 
the 28th, shifting to northeast most of the 29th except the last few 
hours which were east. Southeasterly winds prevailed on the 30th and 
most of the 31st. The maximum velocity of SE-50 occurred at 4:57am EST 
on the 30th and the extreme velocity was 61" (Galveston OMR). "Tides 
continued to increase throughout the 29th until a maximum of 7.6 feet 
on the U.S. Engineer gage at Fort Point was reached at 3am EST on the 
30th. The beach and a considerable portion of the Island west of the 
city was inundated. Tide water covered the Municipal Airport and 
entered the Administration Building.  Water covered the Galveston-
Houston highway at the "Y" on the mainland 10 miles from the city 
until late afternoon of the 30th, and since the Bolivar ferry service 
was suspended, the city was entirely cut off by highway" (Galveston 
OMR). "The barometer began to fall slowly during the afternoon of the 
28th and a rapid fall set in about 10am EST, on the 29th. The lowest sea 
level pressure at the city office was 29.53 inches at 12:55am EST on 
the 30th, and thereafter the barometer rose rapidly until 1 pm EST and 
more slowly thereafter" (Galveston OMR). "The tropical disturbance of 
August 29-30, 1942, was undoubtedly one of the most severe on record 
on the Texas coast with gales and hurricane winds over a path at least 
250 miles wide, and storm tides along the coast from near the central 
region of the path northeastward into southwestern Louisiana" 
(Galveston OMR). "Seadrift, in Calhoun County, where a fairly complete 
calm occurred, reported the lowest pressure along the coast, 951.6mb, 
August 30, at 4:55am. The highest wind at Seadrift was estimated at 
115 miles per hour. Hurricane winds accompanied the storm as far 
inland as Atascosa County. At San Antonio, 120 miles from the coast, 
the storm still retained great strength and caused considerable 
damage" (MWR). "Estimates of damage from the hurricane have been 
placed at $11,500,000 to property and $15,000,000 to crops" (MWR).  
"During the early morning hours of August 30, a tropical disturbance 
of hurricane proportions swept inland over the Matagorda Bay section, 
moved rapidly west-northwestward, and finally diminished over the 
Edwards Plateau region during the late afternoon.  Winds estimated in 
excess of 100 mile per hour occurred along the coast from Austwell to 
Matagorda, and hurricane proportions of the storm were retained as far 
westward as Atascosa County.  Winds of gale force extended well into 
the Edwards Plateau region, and covered a wide area on either side of 
the path of the storm center.  Eight deaths were attributed to the 
storm.  Damage estimated at $11,500,000 occurred to property, while 
crops, principally cotton and rice, suffered damage estimated at 
$15,000,000.  Due to the rain accompanying and following the storm, 
several thousand freshly shorn goats were lost in the Edwards Plateau 
region" (Texas).  "Landfall near Seadrift, estimated lowest pressure 
950 mb (just lower than the 952 mb observed in Seadrift), movement WNW 
13 kt" (Connor). "Aug TX, 3C, 950 mb" (Jarrell et al.). "Aug. 30, 
1942, 951 mb central pressure at landfall, based upon observed 952 mb 
at Seadrift, 18 nm RMW, 14 kt motion, landfall point 28.5N, 96.2W" (Ho 
et al.)

August 31: HWM indicates a closed low of at most 1005mb near 31N, 
103W. HURDAT lists this as a Tropical Depression with 20kt winds at 
32.2N, 101W at 12Z. The MWR Tracks of lows showed a center at 31N, 
101W (am) with a pressure of 999.7mb and at 32N, 105W (pm). Micro 
shows a closed low pressure of at most 999mb at 32N, 103W at 12Z. Ship 
highlights: No gales or low pressures. Station highlights: 15kt W with 
a pressure of 1003mb at Alpine (30.4N, 103.7W) at 12Z (HWM); 17kt S 
with a pressure of 1004mb at San Antonio (29.4N, 98.5W) at 03Z (OMR); 
15 kt NW and 1000 mb at Pecos (31.4N 103.5W) (USWB). "Much damage was 
done by the wind in the vicinity of San Antonio and southward to the 
coast from which came the storm. About $1,500,000 damage resulted from 
torn roofs, windows, sings, windmills, etc. Many trees were uprooted 
or broken by the wind. Many airplanes were destroyed due to lack of 
hanger space, although the planes were well anchored. Power lines were 
down over many sections of the city and southward to the coast" (San 
Antonio OMR). 

September 1: HWM indicates a closed low of at most 1005mb near 33N, 
105W. Micro shows a closed low pressure of at most 1002mb at 31.5N, 
104W at 0Z. Station highlights: 10kt S with a pressure of 1004mb at 
Alpine at 0Z (USWB); 10kt NE with a pressure of 1004mb at Roswell at 
0Z (USWB), and 10kt NW with a pressure of 1005mb at El Paso at 0Z 
(USWB).

Genesis for this major hurricane is delayed by more than two days.  As 
is commonplace during the 1942 hurricane season, almost no ship 
observations were available either in real-time or for the reanalysis 
efforts.  As the system crossed the Lesser Antilles, the observations 
are fairly conclusive that a closed low had not yet developed within 
the strong easterly wave.  Thus the positions on the 21st are removed 
from HURDAT (which began at 06Z on this date originally).  This 
revision is very consistent with the Monthly Weather Review writeup 
for the hurricane as well.  Knowing when genesis did occur over the 
next few days is problematic, as the system was traversing the open 
waters of the Caribbean.  The first indications that a tropical 
cyclone had formed - while still ambiguous - were a report on the 
night of the 23rd in the microfilm which indicated 25 kt winds south of 
Dominican Republic.  More substantial evidence is from Jamaica on the 
24th, which also is in agreement with the Monthly Weather Review 
writeup.  Thus the first entry into HURDAT is now at 12Z on the 23rd as 
a 30 kt tropical depression, though the exact genesis time remains 
uncertain.  Track changes were made for all of the remaining days of 
its existence.  Major track changes were introduced on the 23rd to the 
25th based primarily upon station observations.  A "special report" 
from a Navy aircraft at 18Z on the 25th indicated 1000 mb and wind 40 
to 45 kt (unknown whether this was a surface wind estimate or flight 
level estimate and also unknown if it was measured simultaneous to the 
1000 mb pressure).  This pressure indicates maximum winds of at least 
47 kt from the Brown et al. south of 25N pressure-wind relationship.  
The intensity is reduced to 50 kt, a major reduction from the 80 kt 
originally.  (It is noteworthy that this was one of the first - if not 
the very first - set of quantitative aircraft observations taken 
within a tropical cyclone.)  The modification to the position on the 
26th put the cyclone's center 40 nm northeast of Swan Island around 00Z 
on the 27th.  Swan Island at that time only reported 1003 mb with 15 kt 
W winds.  Thus the intensity is brought down at that time to 60 kt, 
from 90 kt originally.  Likewise, the intensities now have major 
downward revisions from 12Z on the 24th through 06Z on the 27th.  The 
cyclone made landfall in the Yucatan of Mexico around 03Z on the 28th.  
While no specific observations showing hurricane conditions occurred 
in Yucatan, the Monthly Weather Review impacts do suggest a hurricane 
landfall.  90 kt is retained in HURDAT for the Mexican landfall, 
making this a Category 2 impact.  A run of the Kaplan and DeMaria 
inland wind decay model gave 69 kt at 06Z.  Intensity at this time is 
reanalyzed to be 70 kt, down from 85 kt originally.  The hurricane 
moved back over water to the Gulf of Mexico after just six hours over 
land.  No inner core measurements were then available until the 
hurricane made a second landfall in the United States nearly two days 
later.

The hurricane made landfall in Texas around 09Z on the 30th at 28.3N 
96.6W.  A likely central pressure of 952 mb was observed in Seadrift, 
Texas almost an hour later.  The central pressure at landfall may have 
been slightly deeper - 950 mb.  This is in agreement with the original 
Connor estimate of 950 mb, which was repeated in the Jarrell et al. 
tech memo.  950 mb suggests maximum winds at landfall of 105 kt from 
the Brown et al. north of 25N pressure-wind relationship.  The RMW of 
~20 nm is about the same as climatology for this latitude and central 
pressure (Vickery et al.).  The hurricane was moving at a near average 
12 kt at landfall, but had a rather large outer closed isobar of 1007 
mb with ROCI of 250 nm.  Thus the intensity at landfall is estimated 
to be 100 kt, making this a Category 3 landfall for central Texas 
("BTX3").  HURDAT originally had 70 kt at the 06Z slot, which makes 
this a major intensity boost.  A run of the Ho et al. parametric wind 
model suggests peak winds of about 90-95 kt at the western end of the 
north Texas coast (which starts east of Matagorda Bay).  Thus north 
Texas ("CTX") is listed as Category 2 impact from this hurricane.  
After landfall, the hurricane was able to maintain significant 
strength well-inland as noted by the 983 mb peripheral pressure 
observation and 64 kt 1 min NE wind around 16Z on the 30th at San 
Antonio.  This peripheral pressure suggests maximum winds of at least 
69 kt from the north of 25N pressure-wind relationship.  Given its 
overland location, this would be equivalent to at least 60 kt given 
over land conditions.  Runs of the Kaplan and DeMaria inland decay 
model suggest intensities of 74 kt at 12Z on the 30th, 50 kt at 18Z, 
and 33 kt at 00Z on the 31st.  Peak observed winds within 2 hr of 
synoptic time are 53 kt at 12Z, 64 kt at 18Z, and no tropical storm 
force winds at 00Z.  The intensities are reanalyzed to be 85 kt at 
12Z, 65 kt at 18Z, and 45 kt at 00Z (up from 60, 45, and 35 kt, 
originally).  (It should be noted that the Kelly Air Force Base, where 
a 77 kt wind was reported, is southwest of the San Antonio Airport and 
downtown San Antonio.  This would put it closer to the center than the 
San Antonio observation and supports the 85 kt at 12Z.)  Thus major 
intensity upgrades were also made at 12Z and 18Z on the 30th.  
Observations from HWM and the microfilm maps indicate that the cyclone 
continued west-northwestward through 12Z on the 1st of September as a 
weakening tropical cyclone.  In fact, Pecos, Texas recorded 1000 mb 
with NW 15 kt at 12Z on the 1st.  This peripheral pressure suggests 
maximum winds of at least 44 kt from the Brown et al. north of 25N 
pressure-wind relationship.  Given that this is valid over a water 
exposure, a lower intensity value of 35 kt is analyzed at this time. 
The system weakened to a tropical depression - as no extratropical 
transition occurred - around 18Z on the 1st and continued through 12Z 
on the 2nd.  Thus an additional 24 hours are added to the lifetime of 
this system - another major change.

----------------------------------------------------------------------


31940 08/25/1942 M= 9  3 SNBR= 703 NOT NAMED   XING=0 SSS=0
31940 08/25/1942 M=10  4 SNBR= 703 NOT NAMED   XING=0 SSS=0
                   **  *

31945 08/25*  0   0   0    0*275 625  65    0*286 630  65    0*302 635  75    0*
31945 08/25*  0   0   0    0*275 625  65    0*286 630  65    0*300 634  75    0*
                                                                   ***

31950 08/26*314 635  90    0*323 631  95    0*332 622  95    0*342 604  95    0*
31955 08/27*351 587  90    0*356 578  90    0*359 572  85    0*363 567  85    0*
31960 08/28*368 562  80    0*373 557  80    0*377 552  75    0*382 546  75    0*
31960 08/28*368 562  80    0*373 557  80    0*378 552  75    0*382 545  75    0*
                                                                   ***

31965 08/29*388 539  70    0*391 529  70    0*392 519  65    0*391 513  60    0*
31965 08/29*386 539  70    0*389 534  70    0*390 530  65    0*391 527  60    0*
            ***              *** ***              ***              ***

31970 08/30*389 509  55    0*385 507  55    0*381 506  50    0*377 507  45    0*
31970 08/30*391 524  55    0*390 522  55    0*390 520  50    0*388 520  45    0*
            *** ***          *** ***          *** ***          *** ***

31975 08/31*373 510  45    0*370 514  45    0*367 519  45    0*365 522  45    0*
31975 08/31*385 522  45    0*382 526  45    0*380 530  45    0*378 532  45    0*
            *** ***          *** ***          *** ***          *** ***

31980 09/01*364 525  40    0*362 530  40    0*360 537  35    0*357 545  35    0*
31980 09/01*376 534  40    0*373 536  40    0*370 540  35    0*364 547  35    0*
            *** ***          *** ***          *** ***          *** ***

31985 09/02*355 555  30    0*353 567  30    0*352 579  25    0*352 595  25    0*
31985 09/02*360 552  35    0*356 565  35    0*352 579  35    0*348 592  35    0*
            *** ***  **      *** ***  **               **      *** ***  **

(September 3rd is new to HURDAT)

31988 09/03*343 602  30    0*337 607  30    0*330 610  25    0*325 612  25    0*
            *** ***  **      *** ***  **      *** ***  **      *** ***  **

31990 HR  

Minor track and intensity changes are analyzed for this hurricane over 
the central Atlantic.  A major alteration is to add an additional day 
at the end of the cyclone's lifetime.  Evidence for these alterations 
comes from the Historical Weather Maps Series, the COADS ship 
database, Monthly Weather Review, and USWB/NHC microfilm of synoptic 
weather maps.
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Ptarmigan
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Re-Analysis Of The 1955-1964 Atlantic Hurricane Seasons
https://ams.confex.com/ams/31Hurr/webpr ... 5MAR14.pdf

Hurricane Audrey is downgraded from 125 knots (145 mph) to 105 knots (120 mph). There are 12 new tropical cyclones added. I would be interested in Hurricane Carla.
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Ptarmigan
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Reanalysis of Ten U.S. Landfalling Hurricanes
http://www.aoml.noaa.gov/hrd/hurdat/10_ ... icanes.pdf

Houston only experienced tropical storm force winds in the 1945 Hurricane. The radius of maximum wind (RMW) is 18 nautical miles or 20.7 miles. It was a Category 2 at landfall with 105 mph winds. It was quite a rainmaker, where many areas saw 10 to 20 inches of rain.
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Ptarmigan
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Hurricane Camille is more intense at landfall with central pressure of 900 millibars and 175 mph winds. It may have had a low central pressure prior to landfall. Camille is more intense than previously thought. It ties with Gilbert in terms of central pressure at landfall. It is also more intense than Katrina. However, Katrina compared to Camille is much larger in terms of hurricane and tropical storm force winds. Despite Camille making landfall in the same area as Katrina, New Orleans was not flooded like Katrina.

http://www.aoml.noaa.gov/hrd/hurdat/met ... aster.html
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Ptarmigan
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1951 to 1955 Hurricane Season has been re-analyzed.
http://www.aoml.noaa.gov/hrd/hurdat/met ... aster.html

May 2015 - A complete re-analysis of the Atlantic hurricane database (HURDAT) was conducted for
the 1951 to 1955 seasons. Revisions to the hurricane database were accomplished by obtaining the original
observations collected – mainly by ships, weather stations, and the early Hurricane Hunter Navy and Army Air
Force aircraft reconnaissance planes – and assessing the storms based upon our understanding of hurricanes today.
The reanalysis also allowed “discovering” of tropical storms and hurricanes that occurred, but were not yet
officially recognized as such in the official records. Nine hurricanes were identified to have struck the
continental United States during 1951 to 1955, with one new U.S. hurricane (Hazel in 1953) identified and
two hurricanes no longer considered to be hurricane impacts in the United States (Carol in 1954 and Diane
in 1955). Originally, five of these hurricanes were considered to be a major hurricane – Category 3, 4, or 5
on the Saffir-Simpson Hurricane Wind Scale – at U.S. landfall. After the reanalysis, only two were retained
as major U.S. hurricanes: 1954's Carol that struck New York, Connecticut, and Rhode Island as a Category 3
and 1954's Hazel that struck South Carolina and North Carolina as a Category 4. Three other systems were
downgraded to a Category 2 at U.S. landfall: 1954's Edna in Massachusetts, 1955's Connie in North Carolina,
and 1955's Ione in North Carolina. The worst hurricanes during these five hurricane seasons were 1954's
Hurricane Hazel which killed as many as 1200 people in Grenada, Haiti, United States, and Canada and 1955's
Hurricane Janet which killed 681 people in Barbados, Belize, and Mexico. Janet also holds the distinction of
being the strongest hurricane observed during these seasons, reaching Category 5 with peak sustained winds of
175 mph at its landfall in Mexico. In addition, twelve new tropical storms were discovered and added into the
database for this five year period. Andrew Hagen, Sandy Delgado, Donna Sakoskie, Astryd Rodriguez, Brenden Moses,
Chris Landsea, and the Best Track Change Committee all made substantial contributions toward the reanalysis of
these hurricane seasons.
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Ptarmigan
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Re-Analysis Of The 1961-1965 Atlantic Hurricane Seasons
https://www.aoml.noaa.gov/hrd/hurdat/me ... 1-1965.pdf

1961
Carla downgraded from Category 5 to Category 4 with 125 knots/927 millibars and and made landfall 125 knots/931 millibars
Esther is upgraded to Category 5 with 140 knots/919 millibars
Frances is upgraded to Category 4 with 115 knots/948 millibars
Hattie wind is increased to 145 knots/914 millibars and made landfall 130 knots/924 millibars
7 suspected tropical cyclones

1962
New Tropical Storm in late June to early July and made landfall on North Carolina 55 knots/998 millibars
New Hurricane in late November to early December with 80 knots/992 millibars
14 suspected tropical cyclones

1963
Arlene is upgraded to Category 3 with 100 knots/969 millibars and made landfall on Bermuda 95 knots/975 millibars
Cindy downgraded to tropical storm 55 knots/996 millibars at peak and landfall on Texas
Flora increased to 130 knots/933 millibar and landfall on Haiti 130 knots and Cuba 105 knots/973 millibars
Ginny made landfall on Nova Scotia as a Category 2 hurricane 95 kt/948 millibars
New Tropical Storm in June and made landfall on North Carolina at peak of 40 knots
7 suspected tropical cyclones

1964
New Tropical Storm in July that formed from low pressure over South Carolina
New Hurricane in late July to early August with 75 knots/990 millibars
Abby increased to 60 knots/1000 millibars at landfall on Texas
Cleo remains Category 4 peak with pressure lowered to 938 millibars and made landfall on Haiti 130 knots and on Florida as Category 2 95 knots 968 millibars
Dora made landfall on Florida at 95 knots/966 millibars
Hilda made landfall on Louisiana at 90 knots/959 millibars
Isbell made landfall on Florida at 90 knots/970 millibars
14 suspected tropical cyclones

1965
New Tropical Storm in September
New Tropical Storm in late September to early October
New Tropical Storm in October that made landfall on Florida at 55 knots/1004 millibars
Anna increased to 90 knots
6 suspected tropical cyclones
Betsy made landfall on Louisiana at 115 knots/946 millibars
Elena increased to 95 knots/977 millibars
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