000
AXPZ20 KNHC 250245
TWDEP 

TROPICAL WEATHER DISCUSSION                                    
NWS NATIONAL HURRICANE CENTER MIAMI FL                        
0405 UTC MON MAR 25 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0200 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...            
THE MONSOON TROUGH IS PRESENTLY NOT IDENTIFIABLE. THE ITCZ AXIS 
IS VERY WEAK AND EXTENDS FROM 07N85W TO 03N93W THEN RESUMES AT 
03N125W TO BEYOND 01N140W. NO SIGNIFICANT CONVECTION. AS IT IS 
NORMAL FOR THIS TIME OF THE YEAR...A SECOND A BETTER DEFINED 
ITCZ AXIS IS NOTED S OF THE EQUATOR. 

...DISCUSSION...

GAP WINDS...ATTENTION REMAINS FOCUSED ON THE NEXT GAP WIND EVENT 
FORECAST TO TAKE PLACE THROUGH THE GULF OF TEHUANTEPEC BEGINNING 
EARLY MONDAY MORNING. WINDS ARE FORECAST TO INCREASE TO GALE 
FORCE LATE MON NIGHT INTO TUE. COMPUTER MODEL GUIDANCE IS IN 
GENERAL AGREEMENT THAT WINDS WILL FURTHER INCREASE TO 35-40 KT 
LATE TUE NIGHT...WHEN THE GFS ENSEMBLE PROBABILITIES CONTINUE TO 
SHOW A MAXIMUM. SEAS ARE EXPECTED TO BUILD IN EXCESS TO 12-14 FT 
IN ASSOCIATION WITH THE STRONGEST WINDS. A GALE WARNING IS 
ALREADY IN EFFECT BEGINNING AT 26/0600 UTC...AND IS FORECAST TO 
PROBABLY PERSIST UNTIL LATE WED NIGHT. THIS GAP WIND EVENT WILL 
BE ASSOCIATED WITH A STRONG SURGE OF COLD AIR BEHIND A COLD 
FRONT CURRENTLY MOVING SE ACROSS THE GULF OF MEXICO. A STRONG 
NORTH-SOUTH PRES GRADIENT IS FORECAST TO DEVELOP ACROSS THE 
ISTHMUS OF TEHUANTEPEC IN THE WAKE OF THE FRONT. NLY FLOW WILL 
THEN FUNNEL THROUGH THE CHIVELA PASS INTO THE GULF OF 
TEHUANTEPEC...GENERATING THIS GAP WIND EVENT. 

INCREASING TRADE WINDS OVER THE CARIBBEAN REGION ARE FORECAST TO 
EXTEND INTO THE GULF OF PAPAGAYO EARLY WED MORNING...WHEN SURFACE 
WINDS ARE EXPECTED TO REACH 20-25 KT WITH BUILDING SEAS TO 8 FT.

E OF 110W...FAIRLY TRANQUIL MARINE CONDITIONS WILL CONTINUE TO 
PREVAIL DURING THE NEXT 24 HOURS...WITH MAINLY LIGHT TO GENTLE 
WINDS AND SEAS GENERALLY UNDER 6 FT. ONCE AGAIN...SCATTEROMETER 
DATA PROVIDED OBSERVATIONS OF 5-10 KT WINDS ACROSS MOST OF THE 
REGION. SMALL AREAS OF SHOWERS WITH ISOLATED TSTMS WERE NOTED 
WITHIN 30 NM OF A LINE FROM 03N83W TO 03N91W BUT THIS ACTIVITY 
HAVE ALMOST DISSIPATED DURING THE LAST FEW HOURS. A DIFFLUENT 
PATTERN ALOFT IS HELPING TO INDUCE THIS LIMITED CONVECTIVE 
ACTIVITY. 

W OF 110W...A 1024 MB HIGH PRES CENTERED N OF THE AREA AT 
34N130W EXTENDS A RIDGE SE ACROSS THE FORECAST REGION TO NEAR 
18N110W. THE PRES GRADIENT HAS RELAXED ACROSS THE N WATERS AS 
HIGH PRES APPROACHES TO THE DISCUSSION AREA. GENTLE TO MODERATE 
WINDS ARE NOTED PER SCATTEROMETER DATA N OF 20N UNDER THE 
INFLUENCE OF THIS SYSTEM. WINDS SLIGHTLY INCREASE TO 15-20 KT   
ON THE SOUTHERN PERIPHERY OF THE RIDGE. SEAS CONTINUE TO SUBSIDE 
ACROSS THE FORECAST WATERS AND NOW ARE 8 FT IN NW N OF 28N 
BETWEEN 119W AND 124W...AND FROM 15N TO 20N BETWEEN 115W AND 
132W. THESE SWELLS ARE FORECAST BY WAVEWATCH MODEL GUIDANCES TO 
GRADUALLY SUBSIDE TO LESS THAN 8 FT BY 24 HRS.

A COLD FRONT WILL REACH THE FAR NW CORNER OF THE FORECAST AREA 
MON MORNING WITH LITTLE IMPACT....AN WILL BEGIN TO DISSIPATE 
ACROSS THE NW WATERS MON NIGHT.

$$
GR