January: Increasing Clouds/Rain & Warmer To End Month

[srainhoutx]

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
633 AM CST MON JAN 9 2012

TXC339-091300-
/O.CON.KHGX.TO.W.0003.000000T0000Z-120109T1300Z/
MONTGOMERY TX-
633 AM CST MON JAN 9 2012

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 700 AM CST FOR
MONTGOMERY COUNTY...

AT 630 AM CST...THE IAH TERMINAL DOPPLER RADAR CONTINUED TO INDICATE
STRONG ROTATION WITHIN A STORM BETWEEN MAGNOLIA AND THE LAKE CONROE
DAM...OR 9 MILES WEST OF CONROE...MOVING NORTHEAST AT 25 MPH. THIS
STORM COULD PRODUCE A TORNADO...DAMAGING WINDS AND HAIL.

OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO LAKE
CONROE DAM...PANORAMA VILLAGE AND WILLIS

[srainhoutx]

Rotation increasing in Washington County cell. TOR Warning may be needed soon.

[srainhoutx]

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
640 AM CST MON JAN 9 2012

TXZ210>212-226-227-091345-
AUSTIN-COLORADO-FORT BEND-WALLER-WHARTON-
640 AM CST MON JAN 9 2012

...SIGNIFICANT WEATHER ADVISORY...

AT 638 AM CST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM 7 MILES SOUTHWEST OF
BELLVILLE TO 11 MILES WEST OF SEALY TO 20 MILES SOUTHWEST OF EAGLE
LAKE...MOVING EAST AT 20 MPH.

PEA SIZE HAIL...WINDS GREATER THAN 40 MPH...HEAVY DOWNPOURS...ARE
POSSIBLE WITH THESE STORMS.

LOCATIONS IN THE PATH OF THESE STORMS INCLUDE...ROCK ISLAND...NADA...
MONAVILLE...GARWOOD...EGYPT...CAT SPRING...SEALY...SAN FELIPE...
PATTISON...EAGLE LAKE...BROOKSHIRE AND BELLVILLE.

[srainhoutx]

Good news, MAF turned to snow 2 hours before the latest disco from NWS Midland expected...

They said coarser models shows 12Z, NAM was 15Z, and boom, 10Z it was snowing.


WooT!

MESOSCALE DISCUSSION 0009
NWS STORM PREDICTION CENTER NORMAN OK
0651 AM CST MON JAN 09 2012

AREAS AFFECTED...PORTIONS W TX.

CONCERNING...HEAVY SNOW

VALID 091251Z - 091745Z

RAIN-SNOW TRANSITION HAS BEGUN OVER LOWER PECOS REGION GENERALLY
FROM INK-FST. PRIND RATES WILL INCREASE TO 1-2 INCHES/HOUR IN
INCREASINGLY WELL-ORGANIZED PRECIP BAND INITIALLY EXTENDING FROM WRN
PECOS COUNTY NWD OVER WINKLER COUNTY. EMBEDDED TSTMS WILL OFFER
LOCALIZED/BRIEF RATES ABOVE 2 INCHES/HOUR.

SNOW AREA SHOULD PIVOT CYCLONICALLY IN KEEPING WITH EWD SHIFT OF
MID-UPPER LOW...WHILE EXPANDING IN COVERAGE BENEATH ELEVATED MOIST
CONVEYOR. THIS WILL OCCUR AS STRONGEST DEEP-LAYER ASCENT WITHIN
OPTIMAL DENDRITIC-GROWTH LAYER MOVES ACROSS REGION. EXPECT INCREASE
IN SNOW RATES OVER MAF AREA AND NWD/NEWD TOWARD PORTIONS
GARZA/LYNN/TERRY COUNTIES...WHILE HEAVY SNOW AREA SNOW
EXPANDS/SHIFTS EWD ACROSS PORTIONS PECOS/CROCKETT/REAGAN/
GLASSCOCK/HOWARD COUNTIES THROUGH 16Z. SFC TEMPS WILL CONTINUE TO
DECREASE THROUGH MID-LOW 30S F FROM W-E...FROM COMBINATION OF
BOUNDARY-LAYER CAA...WEAK WET-BULB COOLING...AND COLUMNAR DYNAMIC
COOLING. MEANWHILE RELATIVE WARM LAYER BETWEEN 700-800 MB WILL
CONTINUE TO COOL...WHILE RH INCREASES WITHIN DENDRITIC GROWTH COLUMN
AS WELL. THESE PROCESSES WILL FOSTER RAIN-SNOW CHANGEOVER IN ERN
PARTS OF DISCUSSION AREA...AND MAINTAIN SNOW AS DOMINANT
WINTER-PRECIP PHASE. OBSERVED 12Z MAF SOUNDING AND MODIFIED RUC
FCST SOUNDINGS INDICATE THIS TREND...AS WELL AS SUFFICIENTLY STEEP
MIDLEVEL LAPSE RATES TO SUPPORT MUCAPE 100-300 J/KG ROOTED NEAR 700
MB AND EXTENDING INTO ICING LAYERS SUITABLE FOR LTG GENERATION.
THEREFORE OCNL THUNDERSNOW IS EXPECTED OVER MORE OF AREA...WITH LTG
ALREADY DETECTED BETWEEN MAF-FST.

..EDWARDS.. 01/09/2012


ATTN...WFO...SJT...LUB...MAF...

[Andrew]

Out around Montgomery wind direction looks favorable for some rotation but the current storm does look to be decreasing in intensity. That could be a hotspot later on though along with a lot of our northern and western counties. Things do seem to be making there way south so everyone needs to keep their eye on things.

Current Radar:

1-9-2012.png

1 Hour totals:

1-9-2012 (2).png

[srainhoutx]

SPC issues Slight Risk for Severe Storms...

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0643 AM CST MON JAN 09 2012

VALID 091300Z - 101200Z

...THERE IS A SLGT RISK OF SVR TSTMS TODAY OVER THE MIDDLE AND UPPER
TX COAST INTO SWRN LA...

...SYNOPSIS...

MID- AND UPPER-LEVEL LOW CENTERED NEAR OR S OF ELP WILL BEGIN TO
ACCELERATE EWD LATER TODAY IN RESPONSE TO THE APPROACH OF AN
AMPLIFYING UPSTREAM SYSTEM OVER THE PACIFIC NW. AN ASSOCIATED JET
STREAK OVER NRN MEXICO WILL PROGRESS THROUGH BASAL PORTION OF UPPER
LOW...REACHING THE TX COAST INTO SABINE RIVER VALLEY BY TONIGHT. IN
THE LOW LEVELS...A WEAK SURFACE LOW ANALYZED NEAR COT AS OF 12Z WILL
CONCURRENTLY DEVELOP ENEWD NEARLY PARALLEL TO THE TX COAST BEFORE
CURVING NWD/NWWD WHILE OCCLUDING OVER THE SABINE VALLEY. ASSOCIATED
BAROCLINIC ZONE OVER TX WILL LIKELY CONTINUE TO SAG SLOWLY SWD
--AIDED BY CONVECTIVE OUTFLOW-- WHILE REMAINING QUASI-STATIONARY
OVER CNTRL PARTS OF LA...MS AND AL. MEANWHILE...SEGMENT OF BOUNDARY
TRAILING SURFACE LOW WILL ADVANCE MORE RAPIDLY SEWD/SWD AS A COLD
FRONT.

...MID/UPPER TX COAST INTO SWRN LA...

12Z CRP SOUNDING INDICATES THAT LOW-LEVEL AIR MASS HAS MOISTENED
CONSIDERABLY OVERNIGHT WITH DEWPOINTS NOW IN THE UPPER 60S TO AROUND
70 F AND A ML MIXING RATIO OF 14.5 G/KG. GIVEN THE OBSERVED STEEP
MIDLEVEL LAPSE RATES...LOCAL ENVIRONMENT IS ALREADY MODERATELY
UNSTABLE WITH MLCAPE VALUES OF 1000-2000 J/KG. EXPECT WARM SECTOR
TO SHRINK TOWARD THE TX COAST TODAY AS COMPOSITE SURFACE BOUNDARY
ADVANCES SEWD. NONETHELESS...THE STRONGER THAN FORECAST INSTABILITY
WITHIN THE NARROWING WARM SECTOR WILL BE MORE THAN SUFFICIENT TO
SUPPORT EMBEDDED SUPERCELL STRUCTURES GIVEN 40-50 KT OF DEEP-LAYER
SHEAR AND EFFECTIVE SRH OF 100-200 M2/S2. THE GREATEST THREAT FOR A
COUPLE OF TORNADOES...LOCALLY DAMAGING WINDS AND HAIL IS EXPECTED TO
RESIDE FROM THE MID/UPPER TX COAST INTO SWRN LA TODAY.

FOR ADDITIONAL NEAR-TERM GUIDANCE...SEE MCD 8.

...LOWER MS VALLEY/CNTRL GULF STATES...

12Z SOUNDINGS OVER THE LOWER MS VALLEY INDICATE THAT ONLY MODEST
DAYTIME HEATING WILL BE REQUIRED TO BOOST MLCAPE VALUES TO AROUND
1000 J/KG WITH LITTLE OR NO REMAINING CIN. WHILE LARGE-SCALE
FORCING FOR ASCENT WILL REMAIN WEAKER THAN THAT OVER TX...PERSISTENT
LOW-LEVEL WAA AND CONVERGENCE ALONG QUASI-STATIONARY BOUNDARY SHOULD
BE SUFFICIENT TO INITIATE WIDELY SCATTERED TSTMS LATER TODAY. GIVEN
THE PRESENCE OF 40-50 KT WLY FLOW IN THE MIDLEVELS...SUFFICIENT
VERTICAL SHEAR WILL EXIST TO SUPPORT ROTATING STORMS CAPABLE OF
LOCALLY DAMAGING WINDS AND PERHAPS SOME HAIL.

[srainhoutx]

Damage reports in Trinty County from HGX. Also watching cell near Cat Springs as strong downdrafts are showing up.

[srainhoutx]

Folks in Western Harris and Ft Bend Counties heads up. Storm complex moving E along I-10 with 2 inch per hour raindfall rates. Also some rotation noted in NW Harris County with cell near Hockley/Cypress.

[srainhoutx]

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
717 AM CST MON JAN 9 2012

THE NATIONAL WEATHER SERVICE IN LEAGUE CITY HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
SOUTHEASTERN AUSTIN COUNTY IN SOUTHEAST TEXAS...
SOUTHEASTERN COLORADO COUNTY IN SOUTHEAST TEXAS...
NORTHWESTERN FORT BEND COUNTY IN SOUTHEAST TEXAS...
SOUTHERN WALLER COUNTY IN SOUTHEAST TEXAS...
NORTHERN WHARTON COUNTY IN SOUTHEAST TEXAS...

* UNTIL 800 AM CST

* AT 712 AM CST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING WINDS IN
EXCESS OF 60 MPH. THESE STORMS WERE LOCATED ALONG A LINE EXTENDING
FROM SEALY TO EAGLE LAKE TO 17 MILES SOUTHWEST OF EAGLE LAKE...AND
MOVING EAST AT 20 MPH. SMALL HAIL IS ALSO POSSIBLE.

* LOCATIONS IN THE SEVERE THUNDERSTORM WARNING INCLUDE BUT ARE NOT
LIMITED TO EAGLE LAKE...WALLIS...SIMONTON...EAST BERNARD AND
BROOKSHIRE.

[srainhoutx]

Heads up Ft Bend County. Bow echo now suggested.

[Katdaddy]

Wicked dark green skies in downtown Houston. Bow echo headed eastward toward Harris County.

[biggerbyte]

Ft. Bend County... Lookout. Bow Echo coming your way. Expect very strong wind as that area of storms passes by.

[ticka1]

Wicked dark green skies in downtown Houston. Bow echo headed eastward toward Harris County.

Katdaddy do you still work in Allen Center? I'm on the 7th floor - trying to keep an eye on the weather - I am watching that cell come down I-10 towards downtown. It is severe.

[srainhoutx]

HGX monitoring couplet in N Whaton County.

[Katdaddy]

Yes Ticka, I still work across the street from the Allen Center. Powerful cell headed toward Houston metro.

[srainhoutx]

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
742 AM CST MON JAN 9 2012

TXC015-089-157-473-481-091400-
/O.CON.KHGX.SV.W.0001.000000T0000Z-120109T1400Z/
FORT BEND TX-WALLER TX-WHARTON TX-AUSTIN TX-COLORADO TX-
742 AM CST MON JAN 9 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 800 AM CST
FOR COLORADO...AUSTIN...WHARTON...WALLER AND FORT BEND COUNTIES...

AT 738 AM CST...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING
WINDS IN EXCESS OF 60 MPH. THESE STORMS WERE LOCATED ALONG A LINE
EXTENDING FROM SAN FELIPE TO 7 MILES WEST OF EAST BERNARD TO NADA...
OR ALONG A LINE EXTENDING FROM SEALY TO 10 MILES SOUTHEAST OF EAGLE
LAKE TO 13 MILES NORTHWEST OF EL CAMPO...MOVING EAST AT 20 MPH.

OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
EGYPT...WALLIS...PATTISON...HUNGERFORD...SIMONTON...ORCHARD...
KENDLETON AND BROOKSHIRE

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DOPPLER RADAR HAS INDICATED SOME WEAK ROTATION WITHIN THIS STORM.
WHILE NOT IMMEDIATELY LIKELY...A TORNADO MAY STILL DEVELOP. IF A
TORNADO IS SPOTTED...ACT QUICKLY AND MOVE TO A PLACE OF SAFETY IN A
STURDY STRUCTURE...SUCH AS A BASEMENT OR SMALL INTERIOR ROOM.

[srainhoutx]

E-mail update from Jeff:

SPC has just upgraded all of SE TX into a slight risk for severe thunderstorms today.

Moist and unstable warm sector has moved inland and currently resides along and SE of a line from Lufkin to Brenham to NW of Victoria. Air mass south of this line is extremely moist with surface dewpoints of 65-70 degrees. Low level winds are remaining backed to the SE this morning as surface low pressure develops over SW TX. Numerous cells this morning have produce low level rotation and a couple have produced actual wind damage. Air mass over the area is slightly more unstable than models suggest and this is leading to a slight increase in the threat for severe weather and tornadoes. Extremely low cloud bases and favorable helicity values of 300-400 in the surface to 3km level is suggestive of good low level rotation within supercells. Any tornadoes that form will be on the weak side and likely rain wrapped with the extremely moist air mass. Warning lead times will be on the low side. This is the type of set up that produces quick short lived tornadoes with little to no warning.

Additionally, a line of thunderstorms with leading edge bows over southern Austin and northern Wharton Counties currently will likely produce strong winds of 50-60mph into Waller, Wharton and Fort Bend Counties over the next 1-2 hours. The forward bow on the Doppler velocity data over southern Austin County currently is fairly impressive and wind damage is likely in progress along I-10 in this region.

Doppler Radar is also showing storm totals now approaching 4-5 inches over SW Montgomery County where an HP supercell has elongated into a nearly stationary line of heavy rainfall. Significant run-off is likely being generated in this area given the impressive short term rainfall rates of +2.0 inches.

[weatherag]

Hearing claps of thunder in Richmond.....spike in reflectivity between Wallis and East Bernard.

[wxman57]

Update from Jeff Lindner:

"SPC has just upgraded all of SE TX into a slight risk for severe thunderstorms today.

Moist and unstable warm sector has moved inland and currently resides along and SE of a line from Lufkin to Brenham to NW of Victoria. Air mass south of this line is extremely moist with surface dewpoints of 65-70 degrees. Low level winds are remaining backed to the SE this morning as surface low pressure develops over SW TX. Numerous cells this morning have produce low level rotation and a couple have produced actual wind damage. Air mass over the area is slightly more unstable than models suggest and this is leading to a slight increase in the threat for severe weather and tornadoes. Extremely low cloud bases and favorable helicity values of 300-400 in the surface to 3km level is suggestive of good low level rotation within supercells. Any tornadoes that form will be on the weak side and likely rain wrapped with the extremely moist air mass. Warning lead times will be on the low side. This is the type of set up that produces quick short lived tornadoes with little to no warning.

Additionally, a line of thunderstorms with leading edge bows over southern Austin and northern Wharton Counties currently will likely produce strong winds of 50-60mph into Waller, Wharton and Fort Bend Counties over the next 1-2 hours. The forward bow on the Doppler velocity data over southern Austin County currently is fairly impressive and wind damage is likely in progress along I-10 in this region.

Doppler Radar is also showing storm totals now approaching 4-5 inches over SW Montgomery County where an HP supercell has elongated into a nearly stationary line of heavy rainfall. Significant run-off is likely being generated in this area given the impressive short term rainfall rates of +2.0 inches."

[Andrew]

The cell heading for fort bend is very impressive. Radar is sending back a 71.5dbz feedback.