[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 311802
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
105 PM EST THU 31 MAR 2005

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

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1645 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 7N1W 4N20W 3N40W 2N50W.  SCATTERED
MODERATE/ISOLATED STRONG CONVECTION FROM 1N-4N BETWEEN 12W-18W.
WIDELY SCATTERED MODERATE CONVECTION WITHIN 60 NM EITHER SIDE OF
THE AXIS BETWEEN 25W-38W.  SCATTERED MODERATE TO STRONG
CONVECTION S OF 2N BETWEEN 43W-51W INCLUDING COASTAL AREAS OF
BRAZIL FROM 47W TO THE FRENCH GUIANA BORDER.

...DISCUSSION...

GULF OF MEXICO...
STRONG MIDDLE TO UPPER LEVEL RIDGING CURRENTLY PREVAILS ACROSS
THE AREA EXTENDING FROM THE NW CARIBBEAN NWD OVER CUBA AND
FLORIDA THEN UP THE E COAST OF THE UNITED STATES.  THE RIDGE IS
GRADUALLY GIVING WAY TO A POTENT S STREAM CLOSED LOW EMERGING
FROM THE SW UNITED STATES.  ASSOCIATED DYNAMICS ARE MAINLY
FOCUSED N OF THE AREA WHICH IS PRODUCING NUMEROUS
SHOWERS/THUNDERSTORMS FROM THE FLORIDA PANHANDLE NEWD INTO THE
CAROLINAS.  THIS ACTIVITY SHOULD REMAIN PRIMARILY N OF THE AREA
KEEPING THE GULF RELATIVELY DRY UNTIL A COLD FRONT EMERGES OFF
THE SE TEXAS COAST TONIGHT AFTER MIDNIGHT.  THE FRONT WILL
INITIALLY BE MOISTURE STARVED BUT INCREASING LOW LEVEL
CONFLUENCE SHOULD INCREASE THE MOISTURE DURING THE DAY ON
FRIDAY.  EXPECT SHOWERS/THUNDERSTORMS TO INCREASE IN COVERAGE
AND INTENSITY DURING THE DAY AS THE FRONT SWEEPS ACROSS THE
GLFMEX EXTENDING FROM THE FLORIDA PANHANDLE TO THE BAY OF
CAMPECHE BY FRI AFTERNOON. FRONT CURRENTLY FORECAST TO CLEAR S
FLORIDA LATE SAT WITH A LINE OF SCATTERED SHOWERS/
THUNDERSTORMS.  THEREAFTER...MODERATE TO STRONG POST-FRONTAL NLY
FLOW AND DRYING THROUGHOUT THE ATMOSPHERE SHOULD CREATE RAPID
CLEARING FROM WEST TO EAST SAT NIGHT AND SUN.

CARIBBEAN SEA...
THE CARIBBEAN REMAINS UNDER STRONG MIDDLE TO UPPER LEVEL RIDING
WITH A WELL DEFINED ANTICYCLONIC NOTED IN THE UW-CIMSS SATELLITE
DERIVED WIND DATA NEAR 16N81W.  THE RIDGE IS CLIPPED ALONG THE E
SIDE BY A TROUGH DIGGING SWD OVER THE CENTRAL ATLC.  CONFLUENT
FLOW BETWEEN THESE TWO FEATURES IS PRODUCING VERY STRONG
SUBSIDENCE AND DRY/STABLE AIR ALOFT OVER THE E CARIBBEAN.  LOW
LEVEL MOISTURE HAS INCREASED DURING THE LAST FEW DAYS ESPECIALLY
ALONG A LOW LEVEL TROUGH EXTENDING FROM THE VIRGIN ISLANDS TO
THE ABC ISLANDS.  THIS IS CONTRIBUTING TO AN INCREASE IN SHOWER
ACTIVITY MAINLY WITHIN 60 NM EITHER SIDE OF THE TROUGH AXIS N OF
13N. THE TROUGH IS EXPECTED TO CONTINUE WESTWARD POSSIBLY
AFFECTING PORTIONS OF PUERTO RICO WITH SHOWERS/ISOLATED
THUNDERSTORMS DURING THE NEXT DAY OR TWO.  LOOKING FURTHER IN
TIME...NEXT COLD FRONT WILL MARCH ACROSS THE GLFMEX FRI/SAT
APPROACHING THE NW PORTION OF THE CARIBBEAN SAT.  INCREASING
CLOUDINESS AND SHOWERS/THUNDERSTORM MAY AFFECT W PORTIONS OF
CUBA...YUCATAN CHANNEL...AND THE YUCATAN PENINSULA LATE SAT.

ATLANTIC OCEAN...
MIDDLE TO UPPER LEVEL RIDING ALONG THE E COAST OF THE UNITED
STATES COUPLED WITH A TROUGH OVER THE CENTRAL ATLC IS PRODUCING
DRY NW FLOW ACROSS MUCH OF THE W ATLC WATERS.  INCREASING
MOISTURE IN THE UPPER LEVELS IS NOTED W OF 70W IN WATER VAPOR
IMAGERY COURTESY OF AN ACTIVE SUBTROPICAL JET ACROSS THE N
GLFMEX. AT THE SURFACE...990 MB LOW N OF THE AREA TRAILS A COLD
FRONT SWD OVER THE CENTRAL ATLC ENTERING THE AREA ALONG 32N47W
THEN DISSIPATING TO 23N65W.  A NARROW BAND OF SCATTERED
SHOWERS/THUNDERSTORMS IS NOTED WITHIN 90 NM AHEAD OF THE FRONT E
OF 50W AND WITHIN 150 NM AHEAD OF FRONT FROM 50W-60W.  SATELLITE
IMAGERY SHOWS A LARGE FIELD OF OPEN-CELLULAR STRATOCUMULUS
CLOUDS BEHIND THE FRONT TO THE BAHAMAS INDICATED RELATIVELY
STABLE CONDITIONS.   OVER THE E ATLC...DEEP-LAYERED RIDGING
PREVAILS ACROSS MOST OF THE AREA WITH 1021 SURFACE HIGH PRESSURE
CENTERED NEAR 26N41W AND RIDGE AXIS EXTENDING SW TO JUST N OF
PUERTO RICO. A MIDDLE TO UPPER LEVEL TROUGH CLIPS THE FAR NE
PORTION OF THE AREA NEAR THE CANARY ISLANDS WITH ATTENDANT COLD
FRONT N OF THE AREA.  POST-FRONTAL TROUGH ENTERS THE AREA ALONG
32N23W SW TO 25N30W. A FEW WIDELY SCATTERED SHOWERS/ISOLATED
THUNDERSTORMS LIE JUST AHEAD OF THE TROUGH N OF 28N.
ELSEWHERE...DRY/TRANQUIL CONDITIONS PREVAIL.  IN FACT...LATEST
VISIBLE SATELLITE IMAGERY INDICATES A VERY DRY AIRMASS
ORIGINATING FROM AFRICA S AND E OF A LINE FROM W SAHARA TO
10N45W.

$$
RHOME




WWWW
This weather bulletin was brought to you by:
www.nashvilleweather.net