000
AXNT20 KNHC 031752
TWDAT 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL 
205 PM EDT WED APR 03 2013

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...WEATHER OBSERVATIONS...RADAR...AND
METEOROLOGICAL ANALYSIS.

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1715 UTC.

...THE ITCZ/THE MONSOON TROUGH... 

THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL 
ATLC BY SIERRA LEONE NEAR 7N12W AND CONTINUES ALONG 3N18W TO 
EQ24W WHERE THE ITCZ BEGINS AND CONTINUES ALONG EQ30W 1N35W 
1S41W. CLUSTERS OF MODERATE CONVECTION SURROUND THE VICINITY OF 
THE MONSOON TROUGH FROM 4S TO 9N BETWEEN 10W AND 23W. SCATTERED 
SHOWERS ARE N OF THE ITCZ AXIS UP TO 4N BETWEEN 24W AND 30W. 

...DISCUSSION...

GULF OF MEXICO...                                                
A 1010 MB LOW PRESSURE IS LOCATED OVER THE NW GULF NEAR 28N92W 
WITH A COLD FRONT EXTENDING FROM THE LOW SOUTHWESTWARD TOWARDS 
MATAMOROS MEXICO. A WARM FRONT ALSO EXTENDS FROM THE LOW TOWARDS 
THE N-NE GULF ALONG 28N90W 27N87W 26N85W. THIS FRONTAL SYSTEM IS 
BEING SUPPORTED BY A MIDDLE TO UPPER LEVEL CUT-OFF TROUGH OVER 
THE CENTRAL PLAINS. RADAR IMAGERY INDICATE THAT WIDESPREAD HEAVY 
RAINSHOWERS AND THUNDERSTORMS ARE OCCURRING N OF 26N BETWEEN 85W 
AND 92W. EXCEPT FOR THE NW GULF IN THE VICINITY OF THE COLD 
FRONT...SOUTHEASTERLY-SOUTHERLY WIND FLOW OF TO 30 KT SPREAD 
ACROSS THE BASIN. NORTHWESTERLY WINDS OF 5-10 KT ARE W OF THE 
COLD FRONT WHILE SOUTHWESTERLY FLOW OF THE SAME MAGNITUDE 
EXTENDS E OF THE FRONT. OVER THE COURSE OF 24 HOURS...THE LOW 
AND ASSOCIATED COLD FRONT WILL DRIFT EASTWARD POSITIONING 
APPROXIMATELY ACROSS THE FLORIDA PANHANDLE AND EASTERN GULF. N-
NW WIND WILL BUILD W OF THE FRONT AND WINDS UP TO 25 KT WILL 
CONTINUE ACROSS THE BASIN. RAINSHOWERS ARE EXPECTED TO CONTINUE 
AFFECTING THE NORTHERN AND NE PORTIONS OF THE GULF. 

CARIBBEAN SEA...                         
A BROAD MIDDLE TO UPPER LEVEL RIDGE WITH AXIS EXTENDING FROM THE 
EASTERN CONUS TO VENEZUELA IS PROVIDING NEAR WESTERLY FLOW 
ACROSS THE CARIBBEAN. DRY AIR EMBEDDED IN THIS MIDDLE TO UPPER 
LEVEL FLOW IS SUPPORTING FAIR WEATHER CONDITIONS ACROSS MOST OF 
THE BASIN. EASTERLY TRADEWINDS UP TO 20 KT ARE ACROSS THE ENTIRE 
REGION BEING MAINTAINED BY A STRONG PRESSURE GRADIENT. SATELLITE 
COMPOSITE TOTAL PRECIPITABLE WATER IMAGERY INDICATE THAT 
SCATTERED SHOWERS ARE POSSIBLE S OF 15N IN SOUTHERN...CENTRAL 
AND EASTERN CARIBBEAN BEING SUPPORTED BY MOISTURE ADVECTION FROM 
THE E PACIFIC. TRADEWINDS WILL PREVAIL DURING THE COURSE OF 24 
HOURS. 

ATLANTIC OCEAN...                                               
A BROAD MIDDLE-UPPER LEVEL TROUGH N OF 27N OVER THE WEST N ATLC 
IS SUPPORTING A COLD FRONT THAT EXTENDS ALONG 30N59W 27N60W 
24N64W. SCATTERED SHOWERS LIE AHEAD OF THE FRONT FROM 24N-30N 
BETWEEN 50W AND 57W. HOWEVER ISOLATED SHOWERS ARE POSSIBLE ALONG 
THE FRONTAL BOUNDARY. A BROAD SURFACE RIDGE ANCHORED BY A 1031 
MB HIGH NEAR 31N40W SPREADS OVER THE CENTRAL AND EASTERN ATLC N 
OF 17N. THIS SURFACE RIDGE IS BEING SUPPORTED BY A MIDDLE-UPPER 
LEVEL RIDGE BETWEEN 24W AND 57W N OF 21N. WITHIN THE COURSE OF 
24 HOURS...THE FRONT OVER THE W ATLC WILL DRIFT NORTHEASTWARD AS 
A HIGH PRESSURE BUILDS OFF THE CAROLINAS.

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

$$
NR