000
AXNT20 KNHC 231753
TWDAT 

TROPICAL WEATHER DISCUSSION...     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT WED APR 23 2008

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL 
AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN 
SECTIONS OF SOUTH AMERICA...AND THE 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1715 UTC.

...THE ITCZ...

6N11W 2N20W EQ30W CROSSING THE EQUATOR NEAR 40W INTO 
NORTHEASTERN BRAZIL NEAR 1S46W. WIDELY SCATTERED MODERATE 
SHOWERS TO ISOLATED STRONG THUNDERSTORMS WITHIN 90 NM SOUTH
OF THE EQUATOR BETWEEN 11W AND 15W...AND WITHIN 90 TO 120 NM 
NORTH OF THE EQUATOR BETWEEN 33W AND 47W.

...DISCUSSION...

GULF OF MEXICO...

BROAD UPPER LEVEL RIDGE EXTENDS ACROSS THE LOWER MISSISSIPPI 
VALLEY SOUTHWESTWARD INTO THE NORTHWESTERN GULF OF MEXICO. 
BROKEN TO OVERCAST MID-LEVEL CLOUDINESS/MOISTURE ACROSS MUCH OF 
TEXAS IS IN ADVANCE OF DEVELOPING SURFACE LOW PRESSURE CENTER 
LOCATED ACROSS EXTREME WEST TEXAS. SOUTHEASTERLY SURFACE FLOW
WILL DOMINATE THE WESTERN GULF OF MEXICO AND GRADUALLY INCREASE 
DURING THE NEXT 24 HOURS. A 1018 MB HIGH PRESSURE CENTER IS
NEAR 28N88W. THE EASTERN GULF OF MEXICO WILL REMAIN FAIRLY 
TRANQUIL AS A SURFACE RIDGE REMAINS THERE FOR AT LEAST 24 HOURS. 

CARIBBEAN SEA...

LARGELY ZONAL UPPER LEVEL FLOW REGIME DOMINATES MUCH OF THE 
CARIBBEAN SEA. MODERATE TO FRESH TRADEWINDS CONTINUE. THE SURFACE
PRESSURE GRADIENT IS VIRTUALLY NON-EXISTENT ON THE SURFACE MAP. 
ONLY THE 1012 MB ISOBAR CUTS THROUGH THE CARIBBEAN SEA. THE
VISIBLE SATELLITE IMAGERY SHOWS LOW CLOUDS MOVING CYCLONICALLY 
FROM THE SOUTHEASTERN CORNER OF THE AREA...TOWARD HISPANIOLA... 
AND CURVING TOWARD THE SOUTHWESTERN CORNER OF THE AREA.
THE LOW CLOUDS THAT ARE IN THE AREA NORTHWEST OF A LINE FROM 
JAMAICA TO THE NICARAGUA/HONDURAS BORDER ARE MOVING SOUTHWARD.
A LINE OF CONFLUENT FLOW HAS DEVELOPED A THIN CLOUD LINE ALONG
THE JAMAICA-NICARAGUA LINE WITH POSSIBLE SHOWERS. THIN HIGH 
CLOUDS MOVE FROM VENEZUELA ACROSS THE NETHERLANDS ANTILLES AND 
THE SOUTHERN LESSER ANTILLES.

ATLANTIC OCEAN...

A DEEP LAYERED UPPER LEVEL CYCLONIC CIRCULATION CENTER IS NEAR 
29N73W. BROAD AREA OF SURFACE LOW PRESSURE COVERS OPEN ATLANTIC 
OCEAN WATERS FROM 25N TO 32N BETWEEN 63W AND 73W. PAIR OF 
SURFACE TROUGHS EXTEND FROM THIS CENTER. THE EASTERN SURFACE 
TROUGH EXTENDS FROM A 1010 MB LOW PRESSURE CENTER NEAR 29N67W
TO 27N65W 24N66W 21N67W. SCATTERED MODERATE SHOWERS ARE WITHIN 
30 NM TO THE EAST-NORTHEAST OF THE TROUGH. THE WESTERN SURFACE 
TROUGH EXTENDS FROM A 1010 MB LOW PRESSURE CENTER NEAR 29N73W TO 
27N72W TO CROOKED ISLAND BAHAMAS. SCATTERED MODERATE SHOWERS AND 
ISOLATED MODERATE THUNDERSTORMS ARE WITHIN 20 NM TO THE EAST OF 
THE TROUGH. ANOTHER DEEP LAYERED LOW PRESSURE CENTER IS NORTH OF 
THE AREA OVER THE CENTRAL ATLANTIC WITH A 1006 MB LOW CENTERED 
NEAR 35N45W. A SURFACE TROUGH EXTENDS SOUTHWEST FROM THE SURFACE 
LOW TO 33N43W TO 24N50W. ISOLATED SHOWER ACTIVITY IS LOCATED 
WITHIN 20 NM TO THE EAST OF THE TROUGH. A 1024 MB HIGH PRESSURE 
CENTER IS NEAR 34N19W AND IS PROVIDING MODERATE TO FRESH TRADES 
ACROSS MUCH OF THE EASTERN ATLANTIC OCEAN. A TIGHT PRESSURE 
GRADIENT IS ALLOWING NORTH-NORTHEASTERLY WINDS OF 20 TO 30 KTS 
ALONG THE WEST AFRICAN COAST FROM THE NORTHERN MOROCCAN COAST
TO THE CAPE VERDE ISLANDS.

$$
HUFFMAN/MT