000
AXPZ20 KNHC 041510
TWDEP 

TROPICAL WEATHER DISCUSSION                                     
NWS NATIONAL HURRICANE CENTER MIAMI FL                          
1605 UTC SUN MAY 04 2014

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS 
BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND 
METEOROLOGICAL ANALYSIS.

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC. 

...SPECIAL FEATURE...                                            

GULF OF TEHUANTEPEC GALE WARNING...GALE FORCE WINDS CONTINUE 
OVER THE GULF OF TEHUANTEPEC WITH SEAS NEAR 14 FT. THE AREA OF 
HIGH PRESSURE OVER NORTHERN MEXICO AND THE WESTERN GULF OF 
MEXICO HAS SHIFTED EASTWARD. THIS HAS LOOSENED THE PRESSURE 
GRADIENT OVER THE AREA AND IN RESPONSE WINDS HAVE STARTED TO 
DIMINISH OVER THE GULF OF TEHUANTEPEC. WINDS WILL FURTHER 
DIMINISH BELOW GALE FORCE BY THIS AFTERNOON...THEN TO 20 KT OR 
LESS BY MON AFTERNOON. 

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS FROM 07N94W TO LOW PRES NEAR 08N111W 
TO 08N120W WHERE LOW LEVEL WINDS SUGGEST A TRANSITION TO ITCZ 
FROM WHICH EXTENDS TO BEYOND 06N140W. SCATTERED MODERATE 
ISOLATED STRONG CONVECTION WAS NOTED FROM 03N TO 15N BETWEEN 94W 
AND 112W.

...DISCUSSION...                                       

THE MONSOON TROUGH IS VERY ACTIVE AS MENTIONED IN THE 
ITCZ/MONSOON TROUGH SECTION ABOVE. VORTICITY IS INCREASING ALONG 
THE TROUGH...AND IS ESPECIALLY POOLING IN TWO ISOLATED AREAS 
WITHIN THE TROUGH. THE FIRST AREA IS OF ENHANCED VORTICITY IS 
ASSOCIATED WITH THE LOW PRESSURE CENTER NEAR 09N111W WHICH HAS 
BEEN EMBEDDED WITHIN THE MONSOON TROUGH THE PAST DAY OR SO. THE 
OTHER AREA OF ENHANCED VORTICITY WITHIN THE MONSOON TROUGH IS 
NEAR 08N101W. THIS AREA IS ASSOCIATED WITH INCREASED SHEAR 
VORTICITY BETWEEN THE GULF OF TEHUANTEPEC GAP WIND EVENT AND SW 
MONSOON FLOW. THESE AREAS OF ENHANCED VORTICITY WILL BE WATCHED 
WITH CLOSE INTEREST OVER THE NEXT SEVERAL DAYS. THE SCENARIO 
DEPICTED BY GUIDANCE OVER THE PAST FEW DAYS SUGGEST THAT THESE 
VORTICITY CENTERS WILL MERGE OVER THE NEXT COUPLE OF DAYS. THIS 
MERGER WILL HELP FOR A DEEPENED AREA OF LOW PRESSURE...WHICH MAY 
LEAD TO A BREAKDOWN OF THE MONSOON TROUGH...AND FURTHER 
DEVELOPMENT OF THE SURFACE LOW. 
 
HIGH PRESSURE OF 1024 MB IS CENTERED NW OF THE AREA NEAR 34N144W 
WITH RIDGE EXTENDING SE TO NEAR 28N119W. AS A RESULT OF THE WEAK 
RIDGE AND THE DISTANCE OF THE CENTER OF HIGH PRESSURE FROM LOWER 
PRESSURE IN THE VICINITY OF THE ITCZ...THE PRESSURE GRADIENT IS 
LOOSE N OF THE ITCZ AND IS MAINTAINING GENTLE TO MODERATE 
TRADEWINDS N OF THE ITCZ. THE HIGH PRESSURE CENTER IS EXPECTED 
TO SHIFT EASTWARD AND STRENGTHEN SLIGHTLY OVER THE NEXT COUPLE 
OF DAYS. THIS WILL SLIGHTLY TIGHTEN THE PRESSURE GRADIENT OVER 
THE AREA AND RESULT IN MAINLY MODERATE TO LOCALLY FRESH TRADES 
JUST N OF THE ITCZ BY TUE MORNING. 
 
NW SWELLS WITH SEAS TO 8 FEET ARE MOVING THROUGH THE FAR NW 
WATERS. SEAS WILL SUBSIDE TODAY...AND WILL DECREASE BELOW 8 FT 
BY THIS EVENING.

$$ 
AL