000
AXPZ20 KNHC 240316
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC MON FEB 23 2009

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 
0300 UTC.

...ITCZ...
THE INTERTROPICAL CONVERGENCE ZONE IS ALONG THE LINE...09N83W TO 
02N95W TO 03N120W TO 09N140W. THERE IS NO SIGNIFICANT CONVECTION 
ALONG THE ITCZ.

ISOLATED MODERATE CONVECTION IS WITHIN 30 NM EITHER SIDE OF A 
LINE FROM 05N130W TO 12N139W.

...DISCUSSION...

DEEP LAYER TROUGH IS OVER THE NORTHWESTERN PART OF THE AREA. 
THIS FEATURE IS PART OF A LARGE COMPLEX TROUGH THAT EXTENDS 
NORTH OF THE AREA OVER THE PACIFIC OCEAN EAST OF 150W. WEATHER 
ASSOCIATED WITH THE TROUGH IS IN THE FORM OF A PLUME OF UPPER 
LEVEL MOISTURE WITH MULTI LEVEL BROKEN TO OVERCAST CLOUDS 
EXTENDING ABOUT 800 NM SOUTHEAST OF A LINE FROM 32N120W TO 
21N140W. THIS MOISTURE IS DUE TO DIFFLUENT UPPER FLOW TO THE 
EAST OF THE LARGE COMPLEX TROUGH. THE LARGE TROUGH WILL CONTINUE 
THROUGH AT LEAST THE NEXT SEVERAL DAYS WITH SHORTWAVES OR SMALL 
CUTOFF LOWS MOVING THROUGH THE OVERALL CIRCULATION ACROSS THE 
NORTHWEST PART OF THE AREA. THE MOISTURE PLUME SHOULD DIMINISH 
IN A COUPLE OF DAYS AS THE CONVECTION THAT HAS SUPPLIED SOME OF 
THE MOISTURE HAS WEAKENED. HOWEVER SATELLITE IMAGERY INDICATES 
CONVECTION DEVELOPING AGAIN WEST OF 150W WHICH COULD RESUPPLY 
THE SOUTHWESTERLY FLOW WITH MIDDLE AND UPPER MOISTURE.

REMAINDER OF THE MIDDLE AND UPPER LEVELS IS COVERED BY A BROAD 
RIDGE. THE AREA SOUTH OF A LINE SOUTHEAST TEXAS TO TO 15N125W TO 
00N130W IS DRY AND CLOUD FREE IN THE MIDDLE AND UPPER LEVELS 
EXCEPT FOR SOME ITCZ CONVECTION EAST OF 97W.

WEAK SURFACE FRONTAL TROUGH IS OVER THE NORTHWEST PART OF THE 
AREA AND IS ASSOCIATED WITH THE LARGE TROUGH. THE SURFACE TROUGH 
SHOULD CONTINUE THROUGH THE NEXT SEVERAL DAYS. OTHERWISE A WEAK 
RIDGE IS NORTH OF 15N W OF 105W. REMAINDER OF THE AREA IS 
ANALYZED AS A BROAD SURFACE TROUGH CENTERED NEAR THE ITCZ.

GAP NORTHERLY GALE FORCE WINDS IN AND SOUTHWEST OF THE GULF OF 
TEHUANTEPEC REGION WILL DIMINISH TO 20 TO 30 KNOTS TUESDAY AND 
20 TO 25 KNOTS WEDNESDAY.

GAP NORTHEAST TO EAST WINDS IN AND WEST OF THE GULF OF PAPAGAYO 
OF 20 TO 30 KT WILL CONTINUE THROUGH TUESDAY THEN DIMINISH TO 20 
TO 25 KT FOR THE NEXT SEVERAL DAYS. 

$$
LL