General Tropical Discussion Thread

[Andrew]

It wouldn't head our way, would it?

Too early to tell especially if it develops farther west. Gotta love the consistency from the gfs :

[Andrew]

06z GFS:

[srainhoutx]

HPC this morning...

WHILE THE ENS MEANS OF GFS AND ECMWF ARE SIMILAR AND EITHER COULD
BE USED AFTER DAY 5 OVER CONUS THE HPC PREFERENCE IS TOWARDS THE
00Z ECMWF ENS MEAN BASED ON ITS HANDLING OF THE TROPICAL LOW
FORMATION IN THE WRN CARIBBEAN AND ITS SLOWER AND MORE WWD LIFT
NORTHWARD BY THE END OF THE PERIOD. CMC HAS BEEN CONSISTENTLY FAST
WITH ITS EJECTION INTO FL DAYS 4 AND 5 WITH THE 00Z ECMWF PICKING
IT UP BY DAY 5 AND RUNNING IT UP OFF THE ERN SEABOARD DAY 7 SAT.
UKMET HOLDS THE CIRCULATION BACK NEAR YUCATAN THURSDAY NIGHT WITH
GFS OVER CENTRAL CUBA WHERE IT ONLY SLOWLY MOVES BEFORE IT IS
PICKED UP BY LATE SATURDAY AND EJECTED NEWD. BOTH GFS AND ECMWF
ENS MEANS KEEP THE CIRCULATION CENTER IN THE ERN GLFMEX NEAR THE
WRN FL COAST BY DAY 7. WHILE HIGHLY UNCERTAIN THIS IS A BETTER
MATCH TOWARDS THE LAGGED AVERAGE FORECAST LOCATION AND THE
TENDENCY FOR MODELS TO EJECT CARIBBEAN/LOWER GLFMEX SYSTEMS TOO
FAST.

A PATTERN CHANGE FOR ERN CONUS TO COOLER AND QUITE WET WITH THE
CUTOFF LOW EARLY IN THE WEEK AND A LINGERING TROF AND COASTAL
FRONT ESPECIALLY OVER THE SERN SEABOARD LATE WEEK. WELL ABOVE AVG
TEMPS OVER WRN CONUS THIS PERIOD WITH SOME SCATTERED LOCATIONS
ESPECIALY IN THE ROCKIES HAVING NEAR RECORD HIGH TEMPS. A HEAVY
RAIN AND WIND THREAT FOR CUBA AND FLORIDA MID WEEK INTO THE
WEEKEND DEPENDING UPON THE DEVELOPMENT/TRACK AND TIMING OF THE WRN
CARIBBEAN LOW AS IT MOVES SLOWLY NORTHWARD. SEE TPC/HPC
DISCUSSIONS AND POTENTIAL FUTURE ADVISORIES.

[srainhoutx]

Interesting that the PREDICT Team is referring to the Western Caribbean system as the "Big One"...

Date (UTC): 2010/09/25 16:40
Author: Boothe
Submitted at (UTC): 2010/09/25 16:51
--------------------------------------------------------------------------------
Pouch Name: PGI46L Official Name: Matthew Initial Center Point: 15N 84W
Notes:

Matthew is definitely moving westward for the next 36+ hours,
and I was able to determine a phase speed for all of the models.
However, the critical time period is after the initial two days
when either (1) Matthew moves eastward or (2) another system
develops east of Matthew. I decided to just use a phase speed
of 0 m/s because doing so provides a better depiction of the
later system. Also, because we are not flying Matthew now, it
is not critical to get an accurate phase speed for the next two
days.


--------------------------------------------------------------------------------
ECMWF: Phase Speed: 0.0 Determination: Level tracked:

(Phase speed for early forecast: -7.6 m/s)
Track: 72h, then dissipates
ECMWF then develops a another system to the east ... probably
with most of the vorticity coming from a current position in the
southwestern Caribbean.
GFS: Phase Speed: 0.0 Determination: Level tracked:


(Phase speed for early forecast: -6.9 m/s)
Track: 120h, but uncertain at 24 hours.
Matthew weakens over land, but then moves eastward and
reintensifies to become the Big One. As it does so, the GFS
Matthew absorbs the smaller vorticity centers to the east and
southeast that ECMWF develops into the Big One.
UKMET: Phase Speed: Determination: Level tracked:


Unavailable
NOGAPS: Phase Speed: 0.0 Determination: Level tracked:

(Phase speed for early forecast: -5.8 m/s)
Track: 120h
Like GFS, NOGAPS slides Matthew east and reintensifies it as the
Big One (which would most likely be Nicole, by the way....)



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

Other potential systems:
1. Small pouch that is moving westward just to the east of
Matthew. It barely lasts 60 hours in GFS. I track it in ECMWF
out to 120 hours as it becomes the "Big One", but is this small
pouch really the origins of the Big One?

2. A pouch develops that moves eastward in the monsoonal flow
south of Matthew. GFS then turns it northward and appears at
120 hours to be starting to be absorbed by the large Matthew
circulation. ECMWF most likely develops this feature as the
eventual Big One.

3. Pouch near the islands (St. Croix) moving westward has a
small TPW max. GFS only hangs onto it for 24 hours with a
pouch, and out to 60 hours with an OW max.

4. The GFS has a weak pouch up at 16 N latitude out to 72 hours
only.

5. A "micro-midget" is tracked by both GFS and ECMWF down at
925 hPa out to 120 hours.

6. GFS tracks a pouch off of Africa, but the situation is
confused because other weaker pouches are also depicted farther
west.

[srainhoutx]

12Z Euro @ hour 48...

[srainhoutx]

12Z Euro @ hour 168...Look out Key West...

[Ptarmigan]

A complicate setup in the Caribbean leads to a uncertainty. A monsoonal low over the Caribbean and East Pacific is very concerning for Central America. This type of setup is hard to predict and could lead to a hurricane. A situation like this was Wilma in 2005 and Mitch in 1998.

[srainhoutx]

DISORGANIZED CLOUDINESS AND THUNDERSTORMS ARE LOCATED OVER THE
NORTHWESTERN CARIBBEAN SEA. SOME SLOW DEVELOPMENT IS POSSIBLE OVER
THIS AREA DURING THE NEXT COUPLE OF DAYS AS THE SYSTEM MOVES
LITTLE. THERE IS A LOW CHANCE...10 PERCENT...OF THIS SYSTEM
BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS.

[srainhoutx]

HPC:




USED THE 00Z/26 ECMWF FOR THE PRELIMINARY FRONTS AND PRESSURES FOR
DAYS 3 THROUGH 7. THE ECMWF CONTINUES TO BE IN SYNC WITH ITS
ENSEMBLE MEAN...AND BOTH HAVE SHOWN STRONG CONTINUITY FOR SEVERAL
RUNS NOW. THE GFS HAS NOT BEEN AS STABLE...NOR THE GEM GLOBAL AND
UKMET. THE CURRENT GEM GLOBAL TAKES A TROPICAL SYSTEM INTO THE
SOUTHEAST STATES...WITH THE OTHER MODELS HERDING IT INTO THE
ATLANTIC EAST OF THE STRONG BAROCLINIC ZONE. THE UPCOMING PATTERN
IS THE FLIP SIDE TO THE ONE OF THE LAST FEW MONTHS...WITH A DEEP
TROUGH OVER THE EAST AND A FULL LATITUDE RIDGE OVER THE WEST.

[wxman57]

Surface pressures are already quite low in the western Caribbean (1007-1009mb). Lowest pressure is north of Honduras/east of Belize. Banding is starting to show up on satellite imagery, and it's not Matthew's circulation. I'd say there's plenty there to initiate an invest. Development is looking likely, probably in 48-72 hrs. Northward track toward Florida and possibly into or along the East U.S. Coast seems like a good bet.

And I don't think this will be the last of the storms forming there. Low pressures will continue across the region. This may be the 2nd of 3 or 4 storms that form there over the next 2 weeks. Time for Florida's hurricane season.

srain - where are you getting those PREDICT team discussions? They seem to have so many websites set up that I can't find the main one.

[srainhoutx]

srain - where are you getting those PREDICT team discussions? They seem to have so many websites set up that I can't find the main one.

http://catalog.eol.ucar.edu/predict/

[srainhoutx]

[srainhoutx]

A lot of assets set to fly this system...

000
NOUS42 KNHC 261600
WEATHER RECONNAISSANCE FLIGHTS
CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.
1200 PM EDT SUN 27 SEPTEMBER 2010
SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)
VALID 28/1100Z TO 29/1100Z SEPTEMBER 2010
TCPOD NUMBER.....10-117

I. ATLANTIC REQUIREMENTS
1. SUSPECT SYSTEM (NORTHWEST CARIBBEAN)
FLIGHT ONE -- TEAL 70
A. 27/1800Z
B. AFXXX 01GGA INVEST
C. 27/1430Z
D. 18.0N 85.0W
E. 27/1700Z TO 27/2300Z
F. SFC TO 10,000 FT

FLIGHT TWO -- NOAA 49
A. 28/0000Z
B. NOAA9 02GGA SURV
C. 27/1730Z
D. N/A
E. N/A
F. 41,000 TO 45,000 FT

FLIGHT TWO -- TEAL 71
A. 28/0600,1200Z
B. AFXXX 0316A CYCLONE
C. 28/0245Z
D. 19.0N 85.0W
E. 28/0500Z TO 28/1200Z
F. SFC TO 15,000 FT

2. SUCCEEDING DAY OUTLOOK:
A. CONTINUE 6-HRLY FIXES IF SYSTEM DEVELOPS.
B. PROBABLE G-IV MISSION FOR 29/0000Z WITH TAKEOFF
AT 28/1730Z.
3. REMARK: THE NSF/NCAR G-V WILL FLY A 7 HR RESEARCH
MISSION INTO AND AROUND THE SUSPECT AREA BETWEEEN
41,000 AND 43,000 FT WITH TAKEOFF AT 27/1200Z.

[srainhoutx]

The 12Z GFS suggests multiple threats to Florida in the days ahead. Perhaps someone would like to start a new thread for the current Western Caribbean threat that looks to be close to an Invest.

[srainhoutx]

Next Monday, the 12Z GFS suggests another low that would be a TS/Hurricane nearing the SW coast of Florida

[Andrew]

Next Monday, the 12Z GFS suggests another low that would be a TS/Hurricane nearing the SW coast of Florida

Ridge pushes it back south. Could be something for ALL of the gulf to watch.

[Andrew]

Long Long Long Long Long range but has been relatively consistent.

[srainhoutx]

TROPICAL WAVE OVER THE CENTRAL ATLANTIC LOCATED ABOUT 1300 MILES
EAST OF THE WINDWARD ISLANDS IS PRODUCING DISORGANIZED SHOWERS AND
THUNDERSTORMS. DEVELOPMENT...IF ANY...OF THIS SYSTEM IS EXPECTED
TO BE SLOW TO OCCUR AS IT MOVES WESTWARD TO WEST-NORTHWESTWARD AT 15
TO 20 MPH. THERE IS A LOW CHANCE...10 PERCENT...OF THIS SYSTEM
BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS.

[srainhoutx]

PREDICT Team will fly their last mission tomorrow to E of the Windwards for PGI51L. ASCAT pass from today showed some vortisity in the area as well. This may be a sleeper...

[srainhoutx]

Perhaps it's me, but the tropics sure look active...