000
AXPZ20 KNHC 300925
TWDEP 

TROPICAL WEATHER DISCUSSION                                    
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
1005 UTC THU APR 30 2015

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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0900 UTC. 

...SPECIAL FEATURES...

GULF OF TEHUANTEPEC GALE WARNING...A HIGH PRESSURE RIDGE NOSING 
S-SE ACROSS NE AND EASTERN MEXICO HAS BUILT THROUGH THE ISTHMUS 
OF TEHUANTEPEC THIS MORNING...INDUCING STRONG NORTHERLY WINDS 
ACROSS THE GULF OF TEHUANTEPEC. WINDS HAVE INCREASED TO MINIMAL 
GALE FORCE N OF 14N95W THIS AFTERNOON...WHERE SEAS ARE RUNNING 9-
13 FT. WINDS ARE EXPECTED TO DIMINISH TO AROUND 30 KT LATER THIS 
MORNING...THEN GRADUALLY FALL TO NEAR 20 KT BY FRIDAY AFTERNOON.

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

THE MONSOON TROUGH EXTENDS FROM 13N98W TO 07N124W. THE ITCZ 
CONTINUES FROM 07N124W TO 07N140W. SCATTERED MODERATE CONVECTION 
IS WITHIN 75 NM OF THE AXIS BETWEEN 113W AND 129W. AN AREA OF 
SCATTERED MODERATE TO STRONG CONVECTION IS FROM 1.5N TO 05N 
BETWEEN 85W AND 90W.

...DISCUSSION...    

AN ENERGETIC UPPER LEVEL PATTERN DOMINATES THE DISCUSSION AREA N 
OF THE ITCZ. WATER VAPOR IMAGERY SHOWS A SERIES OF SHORT WAVE 
TROUGHS MOVING EASTWARD EMBEDDED IN THE WESTERLY FLOW ALOFT... 
PRODUCING A ZONE OF STRONG UPPER LEVEL DIVERGENCE ACROSS THE 
TROPICS E OF 100W WHERE AREAS OF DEEP CONVECTION CONTINUE TO 
ERUPT EVERY FEW HOURS WITH REGULARITY. MODEL GUIDANCE SUGGESTS 
THIS AREA WILL REMAIN VERY UNSTABLE AND ACTIVE WITH CONVECTION 
THROUGH THURSDAY BEFORE SHIFTING SLOWLY EASTWARD FRI AND SAT.

AT THE SURFACE...A BROAD RIDGE EXTENDS E-SE FROM A 1035 MB HIGH 
PRES N OF THE HAWAIIAN ISLANDS TO NEAR 18N109W. ANOTHER SURGE OF 
N-NW SWELL ASSOCIATED WITH STRONG N WINDS E OF THE RIDGE AND 
ALONG THE CALIFORNIA COAST WILL SWEEP S OF 30N INTO NE PORTION 
OF THE AREA TONIGHT THROUGH THU NIGHT. WINDS E OF 100W ARE LIGHT 
TO MODERATE AS THE EAST-PAC MONSOON CIRCULATION HAS BECOME WELL 
ESTABLISHED ACROSS THE AREA.

LARGE LONG PERIOD SW SWELL GENERATED FROM A VERY LARGE STORM 
SYSTEM ACROSS THE SE PACIFIC WILL MOVE N-NE INTO REGIONAL WATERS 
TODAY AND REACH THE CENTRAL AMERICAN AND MEXICAN COAST SAT...TO 
PRODUCE VERY LARGE AND DANGEROUS WAVES IN THE COASTAL ZONES FROM 
PANAMA TO BAJA CALIFORNIA. A SMALLER PRE-CURSOR PULSE OF THIS SW 
SWELL WILL ARRIVE ALONG THE COASTS FRI AND BE OVERTAKEN ON SAT.

$$
MUNDELL