[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 302335
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT WED MAR 30 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 2330 UTC.

...THE ITCZ...

THE ITCZ AXIS IS ANALYZED FROM THE COAST OF LIBERIA NEAR 5N10W
SW ALONG 2N20W EQ30W 1S40W INTO NE BRAZIL NEAR 2S47W. ISOLATED
WEAK TO MODERATE CONVECTION IS WITHIN 180 NM ON EITHER SIDE OF
THE AXIS BETWEEN W OF 16W.

...DISCUSSION...

THE GULF OF MEXICO...
A MID-UPPER LEVEL TROUGH MOVES ACROSS THE EASTERN HALF OF THE
CONUS SUPPORTING A LOW PRESSURE SYSTEM LOCATED OVER SW GEORGIA.
A COLD FRONT EXTENDS SW FROM THE LOW CENTER ENTERING THE GULF
BASIN THROUGH JUST EAST OF PORT ST JOE FLORIDA AND CONTINUING
ACROSS THE GULF ALONG 26N90W BECOMING STATIONARY NEAR 25N92W TO
VERACRUZ MEXICO. DESPITE THE EXTENSION OF THE FRONTAL SYSTEM
...MOST OF THE INSTABILITY AND LOW-LEVEL CONVERGENCE IS FOCUSED
WITHIN 150 NM EAST OF THE FRONT N OF 27N...AFFECTING THE COASTAL
WATERS FROM SARASOTA TO CEDAR KEY. COMPOSITE DOPPLER RADAR
IMAGERY INDICATES SCATTERED MODERATE TO HEAVY SHOWERS AND
THUNDERSTORMS IN THIS REGION. THIS FRONT WILL CONTINUE TO TRACK
EAST OVER THE NEXT 24 HOURS WITH SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS MOVING SE ACROSS THE FLORIDA STRAITS OVER THE NEXT
24 HOURS.

THE CARIBBEAN SEA...
DRY AIR AND STRONG SUBSIDENCE ALOFT IS NOTED ACROSS THE
CARIBBEAN SEA THIS EVENING. AT SURFACE...FRESH TO STRONG TRADE
WINDS PERSIST WITH VERY FEW AREAS OF SHOWER ACTIVITY. THE FLOW
TURNS SE W OF 75W N OF 16N IN RESPONSE OF THE WEATHER SYSTEM
MENTIONED IN THE GULF OF MEXICO DISCUSSION. THE ONLY FEATURE OF
IMPORTANCE IS A WEAK SURFACE TROUGH MOVING ACROSS PUERTO RICO
ALONG 66W N OF 15N PROVIDING A FEW ISOLATED SHOWERS WITHIN 130
NM ON EITHER SIDE OF THE AXIS. THIS SYSTEM WILL CONTINUE TO MOVE
WNW OVER THE NEXT 24 HOURS. ALSO...SCATTERED SHOWERS ARE
EXPECTED TO DEVELOP OVER THE SW BASIN S OF 14N W OF 75W DURING
THE FORECAST PERIOD.

THE ATLANTIC OCEAN...
A MID-UPPER LEVEL TROUGH IS OVER THE EASTERN HALF OF THE CONUS
SUPPORTING A LOW PRESSURE SYSTEM MOVING OFF THE CAROLINAS AND
ANOTHER LOW PRESSURE SYSTEM LOCATED OVER SW GEORGIA. AS THE TWO
SYSTEMS MOVE OFF THE SEABOARD...SCATTERED MODERATE TO ISOLATED
STRONG CONVECTION IS ALREADY ENTERING THE FAR WESTERN ATLC W OF
74W N OF 27N. DOPPLER RADAR IMAGERY AND LIGHTNING DATA INDICATED
A LINE OF NUMEROUS SHOWERS AND SCATTERED TSTMS OCCURRING WITHIN
THIS AREA OF CONVECTION. THIS SYSTEM WILL CONTINUE TO AFFECT THE
WESTERN ATLC OVER THE NEXT 24 HOURS. A NORTH ATLC DEEP LAYER
TROUGH EXTENDS A FRONTAL SYSTEM THAT ENTERS OUR REGION AS A COLD
FRONT NEAR 32N48W CONTINUING SW ALONG 27N60W TO 28N70W. A PRE
FRONTAL TROUGH IS ANALYZED 50-100 NM AHEAD OF THE FRONT.
SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE WITHIN 70 NM ON
EITHER SIDE OF BOTH THE COLD FRONT AND PRE FRONTAL TROUGH. THIS
FRONTAL BOUNDARY IS EXPECTED TO CONTINUE TO TRACK EASTWARD WITH
CONVECTION OVER THE NEXT 24 HOURS. A WEAK SURFACE TROUGH MOVES
ACROSS PUERTO RICO ALONG 66W S OF 22N PROVIDING A FEW ISOLATED
SHOWERS WITHIN 130 NM ON EITHER SIDE OF THE AXIS. THIS TROUGH
MOVES AROUND THE EXTREME SW PORTION OF A BROAD SURFACE RIDGE
THAT EXTENDS ITS AXIS ACROSS THE EAST AND CENTRAL ATLC. HENCE...
THE REMAINDER OF THE ATLC BASIN IS UNDER THE INFLUENCE OF THIS
BROAD SURFACE RIDGE ANCHORED BY A 1027 MB HIGH CENTERED EAST OF
PORTUGAL NEAR 38N12W.

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

$$

GARCIA



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