000
AXPZ20 KNHC 280953
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC TUE SEP 28 2010

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W.

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0900 UTC.

...ITCZ...

AXIS EXTENDS 11N117W TO 11N124W TO 11N140W. NO SIGNIFICANT 
CONVECTION ASSOCIATED WITH THE ITCZ.

...DISCUSSION...

THE MAIN ISSUE REMAINS STRONG SW TO W WINDS IN THE AREA N OF 05N 
W OF 100W. THE WINDS ARE BEING ENHANCED BY AN AREA OF LOW PRES 
IN THE NW CARIBBEAN. AN ASCAT PASS FROM 03Z SHOWED WINDS TO 20 
KT MAINLY OFF THE CENTRAL AMERICAN COAST FROM EL SALVADOR 
THROUGH NICARAGUA. AS THE AREA OF LOW PRES IN THE CARIBBEAN 
DEVELOPS FURTHER THROUGHOUT TODAY...THESE INFLOWING WINDS OFF 
THE PACIFIC COAST WILL INCREASE FURTHER...REACHING AS HIGH AS 30 
KT BY WED. AS THE CARIBBEAN LOW PRES MOVES N...ITS EFFECTS WILL 
DIMINISH AND THE WINDS OFF THE PACIFIC COAST OF CENTRAL AMERICA 
WILL DIMINISH ACCORDINGLY THROUGH 48 HOURS. THE DEVELOPING LOW 
PRES IN THE CARIBBEAN ALONG WITH A COLD FRONT MOVING INTO THE SW 
GULF OF MEXICO WILL ALSO INITIATE FRESH TO STRONG FLOW THROUGH 
THE GULF OF TEHUANTEPEC LATER TODAY...PERSISTING THROUGH AT 
LEAST WED. ANOTHER AREA OF INTEREST IS AN AREA OF 
QUASI-STATIONARY LOW PRES NEAR 18N107W. SHEAR OVER THE SYSTEM 
HAS DIMINISHED IN THE PAST 24 HOURS. NONETHELESS MODEST E TO SE 
SHEAR CONTINUES AND CONVECTION HAS FLARED INTERMITTENTLY OVER 
THE PAST SEVERAL HOURS TO THE NORTHWEST OF AN EXPOSED LOW LEVEL 
CENTER. SHEAR IS EXPECTED TO DECREASE FURTHER TODAY AS THE LOW 
PRES COMES UNDER AN UPPER LEVEL RIDGE AXIS AND THE CIRCULATION 
AND RELATED CONVECTION WILL LIKELY PERSIST INTO WED. AN ASCAT 
PASS FROM 04Z SHOWED FAIRLY LIGHT FLOW AROUND THIS SYSTEM. 
ELSEWHERE...15-17 SEC LONG PERIOD SWELL CONTINUES TO PUSH SE 
FROM THE N CENTRAL PACIFIC IN TO THE DISCUSSION AREA. ALTIMETRY 
DATA SHOWS SEAS BEGINNING TO SUBSIDE FROM A MAX OF 13 FT OVER NW 
WATERS FROM THIS SWELL TRAIN. THIS INITIAL SWELL TRAIN WILL 
CONTINUE TO SPREAD SE ACROSS NW HALF OF THE BASIN AND GRADUALLY 
SUBSIDE... WHILE A SECOND SURGE OF NW SWELL WILL REACH FAR NW 
WATERS TUE AND BRING THE SEAS BACK TO THE 10 TO 13 FT RANGE THIS 
AFTERNOON. LOOKING AHEAD...LONG PERIOD SW SWELL OF UP TO 15 FT 
WILL PUSH TOWARD THE CENTRAL AMERICAN COAST BY THE WEEKEND.

$$
CHRISTENSEN