000
AXNT20 KNHC 041803
TWDAT 

TROPICAL WEATHER DISCUSSION                                    
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
205 PM EDT MON MAY 04 2015

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.

...ITCZ/MONSOON TROUGH...  
                                   
THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 07N12W TO 
05N13W TO 03N19W WHERE THE ITCZ BEGINS AND CONTINUES ALONG 
02N35W TO THE COAST OF NORTHERN BRAZIL NEAR 01N50W. SCATTERED 
MODERATE AND ISOLATED STRONG CONVECTION ARE FROM THE EQUATOR TO 
08N BETWEEN THE PRIME MERIDIAN AND 17W. WIDELY SCATTERED 
MODERATE CONVECTION IS FROM 03S TO 07N BETWEEN 17W AND 51W.  

...DISCUSSION...

GULF OF MEXICO...                                               
A SHARP MIDDLE TO UPPER LEVEL TROUGH IS OVER THE EASTERN GULF 
WITH AN AXIS EXTENDING FROM 30N88W TO THE WESTERN TIP OF CUBA 
NEAR 22N85W AND OVER THE NORTHWESTERN CARIBBEAN SEA. THE UPPER 
LEVEL TROUGH SUPPORTS A SURFACE TROUGH FROM 29N90W TO 24N89W. 
UPPER LEVEL DIFFLUENCE ON THE BACK SIDE OF THE UPPER TROUGH AND 
CONVERGENCE ASSOCIATED WITH THE SURFACE TROUGH SUPPORTS CLUSTERS 
OF THUNDERSTORMS WITHIN 40 NM OF EITHER SIDE OF THE TROUGH AXIS. 
ANOTHER SURFACE TROUGH EXTENDS ACROSS THE NW CARIBBEAN AND 
WESTERN CUBA AND OVER THE FL STRAITS TO NEAR 23N81W. INTERACTION 
OF THIS SURFACE TROUGH WITH THE UPPER TROUGH IS PRODUCING 
SCATTERED MODERATE CONVECTION WITH THUNDERSTORMS FROM THE COAST 
OF CUBA TO 25N FROM THE BAHAMAS WESTWARD TO 85W. ANTICYCLONIC 
SURFACE FLOW OF 10 TO 15 KT AROUND HIGH PRESSURE OFF THE EASTERN 
US COAST DOMINATES THE BASIN. OVER THE NEXT 24 HOURS THE TROUGH 
OVER THE NORTH-CENTRAL GULF IS FORECAST TO MOVE WEST AND WEAKEN. 
THE UPPER LEVEL TROUGH OVER THE EASTERN GULF WILL CONTINUE TO 
INTERACT WITH A SURFACE TROUGH LIFTING NORTH OUT OF THE FLORIDA 
STRAITS AND THE BAHAMAS. THIS INTERACTION WILL CONTINUE TO 
SUPPORT CONVECTION OVER THE SOUTHEASTERN GULF THROUGH TUESDAY. 

CARIBBEAN SEA...                                               
AN UPPER TROUGH EXTENDS OVER THE EASTERN GULF OF MEXICO AND THE 
EASTERN TIP OF CUBA AND THE NORTHWESTERN CARIBBEAN TO THE COAST 
OF NORTHERN HONDURAS. THE UPPER TROUGH SUPPORTS THE REMNANTS OF 
A FORMER STATIONARY FRONT...NOW A SURFACE TROUGH...THAT EXTENDS 
FROM THE FLORIDA STRAITS AND WESTERN CUBA OVER THE NORTHWESTERN 
CARIBBEAN FROM 20N83W TO 20N85W TO 16N86W. SCATTERED SHOWERS AND 
THUNDERSTORMS ARE FROM 16N TO 10N BETWEEN 81W AND 86W. SCATTERED 
MODERATE CONVECTION IS FROM 20N TO CUBA BETWEEN 77W AND 86W. 
ELSEWHERE...SCATTERED THUNDERSTORMS OVER THE SW CARIBBEAN S OF 
11N ARE ASSOCIATED WITH A SURFACE TROUGH THAT IS OVER 
NORTHWESTERN COLOMBIA AND PACIFIC WATERS. MODERATE TO FRESH 
TRADE WINDS DOMINATE MUCH OF THE CARIBBEAN BASIN THIS AFTERNOON. 
OVER THE NEXT 24 HOURS CONVECTION WILL CONTINUE TO BE LIKELY 
ACROSS THE NORTHWESTERN CARIBBEAN. 
 
...HISPANIOLA...                                              
DRY AND STABLE AIR ALOFT IS MOVING NORTHWESTWARD OVER THE ISLAND 
TODAY. THIS IS SUPPORTING GENERALLY FAIR WEATHER THAT IS 
EXPECTED TO CONTINUE THROUGH TUESDAY. 

ATLANTIC OCEAN...                                              
AN UPPER TROUGH OVER THE EASTERN GULF SUPPORTS A SURFACE TROUGH 
THAT EXTENDS FROM THE NORTHWESTERN CARIBBEAN TO THE FLORIDA 
STRAITS NEAR 24N81W. ANOTHER SURFACE TROUGH...FORMERLY A 
STATIONARY FRONT...EXTENDS FROM THE TAIL END OF A FRONTAL SYSTEM 
NEAR 24N69W TO 21N75W. THESE SURFACE TROUGHS ARE INTERACTING 
WITH THE UPPER TROUGH TO SUPPORT A LARGE DISORGANIZED AREA OF 
SCATTERED MODERATE CONVECTION FROM THE NORTHWESTERN CARIBBEAN 
AND CUBA NORTH TO 26N BETWEEN 71W AND THE FLORIDA KEYS. EAST TO 
NORTHEAST SURFACE WINDS OF 25 KT ARE OCCURRING ACROSS THIS AREA 
OF CONVECTION. FARTHER EAST...A COLD FRONT ENTERS OUR AREA OF 
DISCUSSION NEAR 32N46W TO 27N57W WHERE IT TRANSITIONS TO A 
STATIONARY FRONT TO 24N69W. SHOWERS ARE POSSIBLE WITHIN 50 NM OF 
THE FRONTS. HIGH PRESSURE OF 1023 MB CENTERED NEAR 26N46W COVERS 
THE REMAINDER OF THE CENTRAL ATLC S OF 32S WITH FAIR WEATHER. A 
COLD FRONT EXTENDS OVER THE EASTERN ATLC FROM 32N13W TO 24N35W. 
SHOWERS ARE POSSIBLE WITHIN 50 NM OF THE FRONT. OVER THE NEXT 24 
HOURS CONVECTION IS EXPECTED TO CONTINUE OVER THE BAHAMAS AND 
OFFSHORE WATERS OF THE FLORIDA PENINSULA AS THE UPPER TROUGH 
CONTINUES TO INTERACT WITH SURFACE TROUGHING. 
 
FOR ADDITIONAL INFORMATION PLEASE VISIT 
HTTP://WWW.HURRICANES.GOV/MARINE

$$
LATTO