Atlantic Tropical Weather Discussion

000
AXNT20 KNHC 100004
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL  
705 PM EST MON NOV 09 2009

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL 
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS
OF SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST
FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED
ON SATELLITE IMAGERY...METEOROLOGICAL ANALYSIS...WEATHER 
OBSERVATIONS...AND RADAR.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2230 UTC.

...SPECIAL FEATURES...

TROPICAL STORM IDA IS CENTERED NEAR 28.9N 88.5W AT 10/0000 UTC 
OR ABOUT 40 MILES ESE OF THE MOUTH OF THE MISSISSIPPI RIVER AND 
ABOUT 125 MILES S OF MOBILE ALABAMA MOVING N AT 15 KT. IDA IS 
EXPECTED TO SLOW DOWN AND THE CENTER OF IDA SHOULD REACH THE NRN 
GULF COAST TONIGHT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 993 MB 
REPORTED BY AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT. 
MAXIMUM SUSTAINED WIND SPEED IS 60 KT WITH GUSTS TO 75 KT. SEE 
LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS 
MIATCMAT1/WTNT21 KNHC...OR THE PUBLIC ADVISORY UNDER AWIPS/WMO 
HEADER MIATCPAT1/WTNT31 KNHC FOR MORE DETAILS. SCATTERED STRONG 
CONVECTION IS NEAR THE CENTER FROM 29N-31N BETWEEN 87W-91W...AND 
ACROSS THE SE GULF OF MEXICO FROM 21N-26N BETWEEN 83W-85W. 
SCATTERED MODERATE CONVECTION IS E OF THE CENTER FROM 27N-33N 
BETWEEN 80W-87W. TOTAL RAIN ACCUMULATIONS OF 3 TO 6 INCHES ARE 
EXPECTED WITH MAXIMUM TOTALS OF 8 INCHES FROM CENTRAL AND ERN 
GULF COAST AND ACROSS THE SE UNITED STATES. 

...ITCZ...

THE ITCZ AXIS IS CENTERED ALONG 9N13W 5N24W 6N38W 9N50W 9N61W. 
SCATTERED MODERATE/STRONG CONVECTION IS FROM 5N-9N BETWEEN 
16W-21W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 
2N-8N BETWEEN 23W-27W. SIMILAR ACTIVITY IS FROM 6N-10N BETWEEN 
36W-39W.

...DISCUSSION...

GULF OF MEXICO...
TROPICAL STORM IDA REMAINS THE DOMINANT FEATURE IN THE GULF OF 
MEXICO. SEE SPECIAL FEATURES ABOVE. IDA IS ENCOUNTERING STRONG 
UPPER LEVEL SHEAR WHICH IS KEEPING MOST OF THE CONVECTION TO THE 
NE OF THE STORM CENTER. HOWEVER...A VERTICALLY ORIENTED OUTER 
RAINBAND WITH STRONG THUNDERSTORMS HAS DEVELOPED SE OF THE 
CENTER EXTENDING FROM THE YUCATAN CHANNEL N OF 22N BETWEEN 
83W-86W. THIS RAINBAND LIES UNDER A HIGHLY DIFFLUENT ZONE ALOFT 
BETWEEN AN UPPER LEVEL TROUGH OVER THE WRN GULF W OF 88W AND AN 
UPPER LEVEL RIDGE OVER THE FAR ERN GULF AND FLORIDA E OF 88W. 
STRONG SUBSIDENCE AND DRY AIR ALOFT OVER THE SW GULF LEAVES THE 
REMAINDER OF THE BASIN NOT INFLUENCED BY IDA EXPERIENCING 
GENERALLY FAIR WEATHER. EXPECT IDA TO MOVE INLAND TONIGHT WITH 
CONTINUED STRONG WINDS OVER MUCH OF THE BASIN...AND CONTINUED 
SHOWERS/THUNDERSTORMS NEAR THE SYSTEM. A COLD FRONT IS FORECAST 
TO TRAIL THE REMNANTS OF IDA. 

CARIBBEAN SEA...
SCATTERED SHOWERS/THUNDERSTORMS ASSOCIATED WITH AN OUTER 
RAINBAND OF IDA EXTEND ACROSS THE YUCATAN CHANNEL INTO THE NW 
CARIBBEAN N OF 19N BETWEEN 83W-87W. ISOLATED 
SHOWERS/THUNDERSTORMS ARE ALSO ACROSS THE NRN CARIBBEAN FROM 
17N-20N BETWEEN 77W-82W. ISOLATED SHOWERS/THUNDERSTORMS ARE 
ACROSS THE SW CARIBBEAN S OF 12N BETWEEN 77W-82W IN ASSOCIATION 
WITH SURFACE CONVERGENCE NEAR THE E PACIFIC ITCZ. THE TAIL END 
OF A STATIONARY FRONT EXTENDS FROM THE ATLC INTO THE NE 
CARIBBEAN ACROSS THE LEEWARD ISLANDS TO 17N63W. ISOLATED 
SHOWERS/THUNDERSTORMS ARE FROM 14N-18N BETWEEN 62W-67W. IN THE 
UPPER LEVELS...AN UPPER LEVEL RIDGE COVERS THE WRN CARIBBEAN W 
OF 73W CENTERED NEAR 18N82W. AN UPPER LEVEL TROUGH COVERS THE 
ERN CARIBBEAN E OF 73W CENTERED IN THE ATLC NEAR 26N63W. 

ATLANTIC OCEAN...
THE WRN ATLC IS DOMINATED BY A BROAD SURFACE RIDGE ANCHORED BY A 
1031 MB HIGH N OF THE DISCUSSION AREA NEAR 37N65W. THE SURFACE 
RIDGE IS SUPPORTED BY AN UPPER LEVEL RIDGE EXTENDING FROM THE NW 
CARIBBEAN ACROSS FLORIDA AND THE ERN CONUS AND INTO THE WRN ATLC 
W OF 70W. SCATTERED SHOWERS/THUNDERSTORMS ASSOCIATED WITH IDA 
EXTEND ACROSS FLORIDA AND INTO THE FAR WRN ATLC N OF 30N W OF 
77W. A STATIONARY FRONT EXTENDS FROM A 1016 MB LOW NEAR 43N30W 
ENTERING THE DISCUSSION AREA NEAR 32N44W CONTINUING ALONG 28N53W 
17N63W. SCATTERED SHOWERS/THUNDERSTORMS ARE FROM 15N-28N BETWEEN 
50W-59W. ISOLATED SHOWERS/POSSIBLE THUNDERSTORMS ARE FROM 
27N-32N BETWEEN 46W-62W. THE FRONT IS SUPPORTED BY AN UPPER 
LEVEL TROUGH BETWEEN 50W-70W CENTERED NEAR 26N63W. UPPER LEVEL 
DIFFLUENCE BETWEEN THIS UPPER TROUGH AND A BROAD UPPER LEVEL 
RIDGE COVERING THE ERN ATLC CENTERED NEAR 11N25W IS ALSO 
ENHANCING THE SHOWER/THUNDERSTORM ACTIVITY ASSOCIATED WITH THE 
FRONT. A BROAD SURFACE RIDGE COVERS THE REMAINDER OF THE ERN 
ATLC ANCHORED BY A 1030 MB HIGH NEAR 37N21W. 

$$
WALTON