000
AXPZ20 KNHC 021542
TWDEP 

TROPICAL WEATHER DISCUSSION                                    
NWS NATIONAL HURRICANE CENTER MIAMI FL                           
1605 UTC THU MAY 02 2013

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 
1315 UTC.

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

THE MONSOON TROUGH AXIS EXTENDS FROM 09N84W TO 09N94W. ITCZ AXIS 
CONTINUES FROM 09N94W TO 08N110W TO 06N120W TO 04N140W. NUMEROUS 
MODERATE TO ISOLATED STRONG CONVECTION IS WITHIN 195 NM S OF THE 
MONSOON TROUGH AXIS E OF 85W. SCATTERED MODERATE CONVECTION IS  
WITHIN 180 NM S OF THE ITCZ AXIS BETWEEN 92W AND 95W. SCATTERED 
MODERATE CONVECTION IS WITHIN 150 NM EITHER SIDE OF THE ITCZ 
AXIS BETWEEN 112W AND 134W.
 
...DISCUSSION... 

A COLD FRONT WILL MOVE THROUGH THE GULF OF MEXICO FRI AFTERNOON 
WITH STRONG HIGH PRES BUILDING BEHIND THE FRONT. THE HIGH WILL 
TIGHTEN THE PRES GRADIENT ACROSS SOUTHERN MEXICO RESULTING IN 
GALE FORCE WINDS THROUGH THE GULF OF TEHUANTEPEC FRI AFTERNOON. 
THE GALE WARNING WILL REMAIN IN EFFECT UNTIL SATURDAY MORNING.  

A TIGHT PRESSURE GRADIENT BETWEEN THE SW UNITED STATES AND THE 
GULF OF CALIFORNIA IS GENERATING NW WINDS UP TO 25 KT N OF 30N 
THIS MORNING. THIS EVENT IS EXPECTED TO DIMINISH BY FRIDAY 
MORNING AS THE PRESSURE GRADIENT WEAKENS. DURING THAT PERIOD 
SEAS ARE EXPECTED TO BE UP TO 8 FT. 

THE GALE FORCE WINDS W OF THE NORTHERN CALIFORNIA COAST HAVE 
WEAKENED BUT N SWELLS AND SEAS UP TO 10 FT CONTINUE FROM 26N-32N 
BETWEEN 120W AND 137W. THESE SWELLS ARE EXPECTED TO SUBSIDE THIS 
EVENING.  

HIGH MID-TO LOW-LEVEL MOISTURE COMBINED WITH UPPER LEVEL 
DIVERGENCE ASSOCIATED WITH UPPER LEVEL RIDGING IS ENHANCING  
NUMEROUS MODERATE TO ISOLATED STRONG CONVECTION WITHIN 195 NM S 
OF THE MONSOON TROUGH AXIS E OF 85W. THIS CONVECTION IS EXPECTED 
TO CONTINUE THROUGH EARLY SATURDAY SUPPORTED BY UPPER LEVEL 
DIVERGENCE. 

$$
NR