000
AXPZ20 KNHC 051514
TWDEP 

TROPICAL WEATHER DISCUSSION                                     
NWS NATIONAL HURRICANE CENTER MIAMI FL                          
1605 UTC MON MAY 05 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. 

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

THE MONSOON TROUGH EXTENDS FROM 06N89W TO LOW PRES NEAR 09N112W 
TO 08N117W WHERE LOW LEVEL WINDS SUGGEST A TRANSITION TO ITCZ 
WHICH EXTENDS TO 06N120W TO 06N128W TO BEYOND 05N140W. SCATTERED 
MODERATE ISOLATED STRONG CONVECTION WAS NOTED WITHIN 90 NM N AND 
120 NM S OF TROUGH BETWEEN 89W AND 97W. SCATTERED MODERATE TO 
STRONG CONVECTION WAS NOTED WITHIN 270 NM OF TROUGH BETWEEN 97W 
AND 102W. SCATTERED MODERATE ISOLATED STRONG CONVECTION 
WAS NOTED WITHIN 90 NM E SEMICIRCLE OF LOW.

...DISCUSSION...                                       

TWO AREAS OF ACTIVE CONVECTION ARE EMBEDDED WITHIN THE MONSOON 
TROUGH. THE FIRST AREA IS ASSOCIATED WITH A SURFACE LOW CENTERED 
NEAR 09N112W. THE SECOND AREA WAS ASSISTED BY SPEED CONVERGENCE 
INTO THE MONSOON TROUGH FROM THE PREVIOUS GAP WIND EVENT. THIS 
AREA HAS A WELL DEFINED MID LEVEL CIRCULATION. THE FORECAST OVER 
THE NEXT COUPLE OF DAYS HAS A LOT OF UNCERTAINTY. THE GENERAL 
CONSENSUS OF THE GUIDANCE OVER THE PAST COUPLE OF DAYS IS FOR 
THESE AREAS OF ENHANCED VORTICITY TO MERGE...WITH THE SURFACE 
LOW SHIFTING N THEN NE WHILE INTERACTING WITH AN UPPER LEVEL 
TROUGH. HOWEVER...THERE ARE SIGNIFICANT DIFFERENCE BETWEEN 
GUIDANCE WITH THE STRENGTH OF THE LOW PRESSURE WHICH IS RELATED 
TO THE POSITION OF THE UPPER TROUGH IN RELATION TO THE SURFACE 
LOW AND THE RESULTANT SHEAR. THE TREND FOR THE ECMWF AND UKMET 
HAS BEEN TOWARD A WEAKER LOW WHILE THE GFS HAS A MUCH STRONGER 
LOW. THE OFFICIAL FORECAST WILL CONTINUE TO FOLLOW THE GFS TREND 
FOR DEVELOPMENT AND POSITION BUT WITH A NOD TO THE ECMWF/UKMET 
FOR INTENSITY FOR LATER PERIODS.
 
HIGH PRESSURE OF 1026 MB IS CENTERED N OF THE AREA NEAR 34N139W 
WITH RIDGE EXTENDING SE TO NEAR 28N116W. THE PRESSURE GRADIENT 
BETWEEN THIS AREA OF HIGH PRESSURE AND LOWER PRESSURE IN THE 
VICINITY OF THE ITCZ IS MAINTAINING GENTLE TO MODERATE 
TRADEWINDS N OF THE ITCZ W OF 120W. THE AREA OF HIGH PRESSURE 
WILL BUILD SLIGHTLY OVER THE NEXT COUPLE OF DAYS. THIS WILL 
TIGHTEN THE PRESSURE GRADIENT AND FRESHEN TRADE WINDS N OF THE 
ITCZ BY MIDWEEK. AS THE AREA OF HIGH PRESSURE BUILDS...THE 
PRESSURE GRADIENT E OF THE AREA OF HIGH PRESSURE WILL TIGHTEN 
AND STRENGTHEN WINDS N OF 28N WITHIN 180 NM W OF BAJA CALIFORNIA 
NORTE BY TUE NIGHT.

$$ 
AL