[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 191145
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT SAT MAR 19 2011

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTION 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1045 UTC.

...ITCZ...

THE ITCZ AXIS IS ALONG 7N11W 2N20W CROSSING THE EQUATOR AT 25W
THEN CONTINUES ALONG 2S30W INTO NE BRAZIL NEAR 5S38W. SCATTERED
MODERATE TO STRONG CONVECTION IS INDICATED FROM THE EQUATOR TO
2N BETWEEN 18W AND 28W. SCATTERED MODERATE ISOLATED STRONG
CONVECTION WAS NOTED FROM 2N TO 5N BETWEEN 8W AND 15W. ISOLATED
MODERATE CONVECTION IS NOTED WITHIN 45 NM EITHER SIDE OF A LINE
FROM 2N30W TO 3N37W.

...DISCUSSION...

GULF OF MEXICO...
A 1025 MB SURFACE HIGH PRESSURE LOCATED OVER THE NORTH CENTRAL
GULF NEAR 28N88W DOMINATES MOST OF THE GULF OF MEXICO AND THE
STATE OF FLORIDA PRODUCING FAIR WEATHER CONDITIONS...EXCEPT FOR
OVERCAST LOW CLOUDS ALONG THE COAST OF MEXICO AND SE TEXAS.
WINDS ARE LIGHT AND VARIABLE NEAR THE HIGH PRES CENTER...WITH
MODERATE TO FRESH EASTERLY AND WINDS ON THE SOUTHERN PERIPHERY
OF THE HIGH WITH SOUTHEASTERLY RETURN FLOW OVER THE WESTERN GULF
WATERS. THE BAND OF TRANSVERSE HIGH CLOUDS NOTED EARLIER OVER
THE SOUTHERN GULF HAS BECOME LESS DEFINED AS THE AREA MOVES SE
INTO THE FAR NW CARIBBEAN. MODERATE TO STRONG SUBSIDENCE AND THE
IMPLIED DRY AIR MASS IS SEEN N OF 25N INCLUDING THE GULF COAST
STATES AND FLORIDA WHERE MILD AND DRY WEATHER CONDITIONS ARE
EXPECTED TO CONTINUE THROUGH TODAY. THE SURFACE RIDGE IS
FORECAST TO REMAIN NEARLY STATIONARY OVER THE NEXT SEVERAL DAYS
AND CONTINUE TO PROVIDE OVERALL STABLE WEATHER CONDITIONS.

CARIBBEAN SEA...
AN UPPER LEVEL ANTICYCLONIC CIRCULATION CENTERED IN THE TROPICAL
ATLANTIC NEAR 7N32W EXTENDS A RIDGE OVER MOST OF THE CARIBBEAN
WITH SW WINDS ALOFT OVER THE BASIN. MODERATE TO STRONG
SUBSIDENCE IS ASSOCIATED WITH THIS RIDGE LIMITING THE
DEVELOPMENT OF ANY DEEP CONVECTION. SHALLOW MOISTURE EMBEDDED IN
THE TRADE WIND FLOW WILL CONTINUE TO AFFECT THE REGION
GENERATING ISOLATED TO SCATTERED PASSING SHOWERS. A BAND OF LOW
LEVEL CLOUDS WITH EMBEDDED SHOWERS IS NOTED WITHIN 120 NM OF THE
COAST OF COLOMBIA.
SURFACE HIGH PRES LOCATED OVER THE NE GULF AND PORTIONS OF THE
SW NORTH ATLANTIC CONTINUES TO PRODUCE A LARGE AREA OF FRESH TO
STRONG NE TRADES OVER MUCH OF THE CARIBBEAN WITH THE STRONGEST
WINDS NEAR THE COAST OF COLOMBIA. A SHIP WITH CALL SIGN ZCDF4
REPORTED NE WINDS OF 25-30 KT WITHIN THE PAST HOUR. ANOTHER SHIP
WITH CALL SIGN 5RDK2 REPORTED NE WINDS OF 25 KT. NE WINDS OF 2O
KT CAN BE FOUND OVER THE NW CARIBBEAN AND JUST SOUTH OF
DOMINICAN REPUBLIC. LOW LEVEL NE WINDS ARE BANKING CLOUDS OVER
PANAMA AND COSTA RICA. THE SURFACE FLOW IS FORECAST TO REMAIN
QUITE BRISK THROUGH THE WEEKEND AND INTO MON AS A STRONG HIGH
PRES BUILDS OVER THE W ATLANTIC.

ATLANTIC OCEAN...
HIGH PRES AT THE SURFACE AND ALOFT DOMINATES THE WESTERN ATLC W
OF 65W WITH MOSTLY FAIR WEATHER CONDITIONS. THE COMBINATION OF
THIS HIGH AND GENERAL TROUGHINESS ALONG 60W IS RESULTING IN
FRESH NE WINDS ACROSS THE SOUTHERN BAHAMAS AND THE GREATER
ANTILLES. THESE WINDS ARE FORECAST TO PERSIST THROUGH SAT
NIGHT...AND INCREASE LATER TODAY AND MON AS STRONG HIGH PRESSURE
BUILDS IN FROM THE NORTH. SURFACE DATA AND A 0200 UTC ASCAT PASS
INDICATED NE WINDS OF 20 KT NEAR THE SE BAHAMAS AND 25 KT WINDS
IN THE WINDWARD PASSAGE. AN UPPER LEVEL TROUGH WITH AXIS
EXTENDING FROM A SMALL BUT VIGOROUS UPPER-LEVEL LOW NEAR 29N59W
TO 22N64W. THE UPPER LOW WAS SWEEPING TO THE ESE AT 10-15 KT.
UPPER DIFFLUENCE AHEAD OF THE UPPER LEVEL TROUGH AND LOW IS
AIDING IN THE DEVELOPMENT OF EXPANDING AREA OF DEEP LAYERED
CLOUDINESS WITH SCATTERED SHOWERS AND TSTMS ALONG AND WITHIN 300
NM TO THE N OF A STATIONARY FRONT WHICH EXTENDED FROM 21N45W TO
25N50W TO A DEVELOPING 1012 MB LOW NEAR 25N54W. A 1014 MB LOW
WAS LOCATED FURTHER NW NEAR 28N58W WITH A SURFACE TROUGH
EXTENDING SWD THROUGH 25N58W TO 22N62W. ANOTHER SURFACE TROUGH
EXTENDED FROM 21N58W TO 15N59W. FURTHER EAST...A STATIONARY
CUT-OFF LOW IS NEAR 36N30W WITH A NEGATIVELY TILTED TROUGH
EXTENDING S AND SE TO NEAR 24N23W. THIS UPPER LEVEL FEATURE IS
PROVIDING MARGINAL SUPPORT FOR A SURFACE TROUGH THAT ENTERS THE
DISCUSSION AREA NEAR 31N25W THEN CONTINUES SW TO 22N31W. A 1026
MB HIGH PRES SITUATED NEAR 34N43W IS BUILDING SE IN THE WAKE OF
THE SURFACE TROUGH.

FOR ADDITIONAL INFORMATION PLEASE VISIT
HTTP://WWW.HURRICANES.GOV/MARINE

$$
COBB





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