000
AXPZ20 KNHC 020349
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC TUE SEP 02 2008

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

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY 
THROUGH 0330 UTC.

...SPECIAL FEATURE...

LOW PRES FORMED NEAR 18N110W 1004 MB DURING THE DAY...AND IS
MOVING WNW ABOUT 8 KT. NUMEROUS STRONG CONVECTION IS WITHIN 
OF CENTER IN W QUADRANT. SCATTERED MODERATE CONVECTION IS 
ELSEWHERE WITHIN 180 NM OF CENTER OVER THE W SEMICIRCLE.
THIS SYSTEM IS NOW UNDER MORE FAVORABLE CONDITIONS FOR IT
TO BECOME A TROPICAL DEPRESSION WITHIN THE NEXT 48 HOURS...
HOWEVER LATEST SATELLITE IMAGERY SHOWS THAT THIS SYSTEM IS 
UNDERGOING UPPER LEVEL EASTERLY SHEAR...SO ANY DEVELOPMENT 
SHOULD BE SLOW TO OCCUR.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 10N86W 12N96W 11N110W 09N120W 
7N140W. SCATTERED MODERATE CONVECTION IS WITHIN 120 NM S OF THE 
AXIS BETWEEN 95W-100W...AND BETWEEN 131W-137W.

...DISCUSSION...

A RIDGE EXTENDS WSW FROM THE ANTICYCLONE CENTERED NEAR 
21.5N105.5W TO 22N118W TO 18N126W. ASSOCIATED MODERATE TO STRONG 
SUBSIDENCE MAINTAINS VERY DRY AIR MASS N OF 14N W OF 112W...
AND IS SUPPRESSING ANY DEEP CONVECTION FROM FORMING. MAIN
MOISTURE AREA IS ASSOCIATED WITH THE ITCZ.

AT THE SURFACE...
RIDGE EXTENDS SE THROUGH 32N135W TO 26N126W. HIGH PRES COVERS
THE AREA N OF 22N W OF 130W. THE ATTENDANT HIGH CENTER ANALYZED
AS 1030 MB N OF AREA NEAR 40N140W IS INTERACTING WITH 
LOW PRES OVER THE SW UNITED STATES TO PRODUCE N-NE WINDS OF
20-25 KT OVER THE N AND NW PORTIONS OF THE AREA WITH SEAS UP
TO 13 FT IN NE SWELL. THESE CONDITIONS ARE FORECAST TO LAST
THROUGH THE NEXT 48 HOURS.

SW WIND FIELD S OF MONSOON TROUGH COMBINED WITH CROSS EQUATORIAL 
SWELLS ARE CAUSING 8-11 FT SEAS WITHIN 180 NM S OF LINE 12N91W
12N101W...AND ALSO FROM 5N TO 12N BETWEEN 91W AND 122W. THESE
CONDITIONS WILL LIKELY LAST THROUGH THE NEXT 2-3 DAYS BEFORE 
SUBSIDING. SOME OF THESE SWELLS MAY REACH THE CENTRAL AMERICAN 
COAST IN THE 8-9 FT RANGE. 

GLOBAL MODELS SUGGEST THAT A NEW LOW PRES AREA MAY FORM ON THE
EASTERN END OF THE MONSOON TROUGH OVER THE NEXT 2-3 DAYS...AND
FURTHER ENHANCE THE SW WINDS IN THIS AREA.

$$
AGUIRRE