000
AXPZ20 KNHC 051530
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SAT SEP 05 2009

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

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

...THE ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE IS ALONG THE LINE...08N78W TO 
09N105W TO 11N120W TO 11N140W. SCATTERED MODERATE TO STRONG 
CONVECTION IS WITHIN 90 NM OF 10N112W. SCATTERED MODERATE TO 
STRONG WITHIN 60 NM OF 11N117W. 

...DISCUSSION...

AN UPPER ANTICYCLONE CENTERED NEAR 25N137W WITH A RIDGE  
EXTENDING MAINLY E TO W ALONG 20N...DOMINATES THE AREA WEST OF 
110W PRODUCING MODERATE TO STRONG SUBSIDENCE. E OF THE RIDGE 
THERE IS AN UPPER-LEVEL TROUGH WITH AXIS ALONG 105W WITH THE 
TROUGH EXTENDING TO 100W. THE BASE OF THIS TROUGH REACHES 17N. 
ANOTHER ANTICYCLONE IS OVER SOUTH-CENTRAL MEXICO FROM 100W TO 
93W. A NARROW TROUGH EXTENDS FROM 93W TO 89W WITH ANOTHER RIDGE 
EAST OF 89W.

THE REMNANTS OF JIMENA...ANALYZED AS A TROUGH AT 05/0600 
UTC...ARE PRODUCING SOME CLOUDINESS OVER SOUTHERN BAJA 
CALIFORNIA. WHILE DEEP CONVECTION ENDED SEVERAL HOURS AGO...LOW 
TOPPED SHOWERS ARE STILL OCCURRING. ACCORDING TO THE COMPUTER 
MODELS...A TROUGH AND THE ASSOCIATED MOISTURE FIELD IS EXPECTED 
TO PERSIST OVER THIS REGION DURING THE NEXT 24 TO 48 HOURS. 

A BROAD AREA OF LOW PRESSURE IS CENTERED NEAR 15N119W MOVING 
W-NW ABOUT 10 KT. DEEP CONVECTION HAS DECREASED OVERNIGHT AND 
REMAINS DISPLACED NORTHWEST OF THE CENTER. SCATTERED MODERATE 
WITH ISOLATED STRONG CONVECTION IS WITHIN 75 NM EITHER SIDE OF A 
LINE FROM 18N116W TO 14N122W. UPPER-LEVEL WINDS APPEAR CONDUCIVE 
FOR SOME SLOW DEVELOPMENT OF THIS SYSTEM DURING THE FEW DAYS. 
CURRENTLY...THERE IS A LOW CHANCE OF THIS SYSTEM BECOMING A 
TROPICAL CYCLONE DURING THE NEXT 48 HOURS. 

THE REMNANT LOW FROM KEVIN IS STILL EVIDENT ON SATELLITE IMAGERY 
WHERE A WELL DEFINED SWIRL OF LOW CLOUDS IS NOTED. A TROUGH IS 
ANALYZED ALONG 126W FROM 20N TO 15N AT 05/1200 UTC AND IS MOVING 
WEST 10 KT. A RECENT ASCAT PASS SHOWS NE WINDS OF 20 KT WITHIN 
180 NM NW SEMICIRCLE OF THE LOW. THIS LOW SHOULD DISSIPATE 
WITHIN THE NEXT 24 HOURS.

A SURFACE RIDGE IS BEGINNING TO ESTABLISH OVER THE NORTHERN 
FORECAST WATERS MAINLY N OF 20N WITH A MODEST INCREASE IN THE 
TRADEWINDS IN THE WESTERNMOST PORTION OF OUR DOMAIN PARTICULARLY 
BETWEEN 15N AND 22N AND W OF 135W. NE WINDS OF 20 KT AND SEAS TO 
8 FT ARE EXPECTED. 

A WEAK PAPAGAYO WIND EVENT WILL PERSIST DURING THE NEXT FEW DAYS 
REACHING 20 KT MAINLY DURING THE MORNING HOURS. 

LONG PERIOD NW SWELLS ARE EXPECTED TO INVADE THE N WATERS IN 
ABOUT 48 HOURS.

$$
LL