000
AXPZ20 KNHC 230317
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...09N84W TO 
02N95W TO 02N115W TO 08N130W TO 06N140W. SCATTERED MODERATE 
CONVECTION IS WITHIN THE AREA FROM 05N TO 06N BETWEEN 84W AND 
92W. SCATTERED MODERATE CONVECTION IS WITHIN THE AREA FROM 06N 
TO 09.5N BETWEEN 127W AND 132W.

...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. SEVERAL 
CUTOFF LOWS ARE EMBEDDED WITHIN THE OVERALL TROUGH AND ONE IS 
LOCATED NEAR 32N135W AND IS MOVING NORTHEAST 30 KT. WEATHER 
ASSOCIATED WITH THE TROUGH IS IN THE FORM OF A PLUME OF UPPER 
LEVEL MOISTURE WITH MULTI LEVEL OVERCAST CLOUDS WITH SOME 
EMBEDDED RAIN WITHIN 150 NM EITHER SIDE OF A LINE FROM 20N135W 
TO BEYOND 32N125W. THIS MOISTURE EMANATES FROM DIFFLUENT UPPER 
FLOW TO THE EAST OF A DEEP TROPICS TROUGH THAT HAS BEEN LOCATED 
WEST OF THE AREA. THE DEEP TROPICS TROUGH IS BEING ABSORBED BY 
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 AS THE 
CONVECTION THAT HAS SUPPLIED SOME OF THE MOISTURE HAS WEAKENED.

REMAINDER OF THE MIDDLE AND UPPER LEVELS IS COVERED BY A BROAD 
RIDGE. CONVECTION NEAR THE ITCZ FROM 84W TO 94W IS INTRODUCING 
MIDDLE AND UPPER LEVEL MOISTURE WITH BROKEN CLOUDS IN THE UPPER 
SOUTHWESTERLY FLOW. THESE CLOUDS ARE MOVING OVER WESTERN PANAMA 
AND COSTA RICA AND SOUTHERN NICARAGUA. OTHERWISE THE AREA SOUTH 
OF A LINE FROM NEAR THE BIG BEND OF THE RIO GRANDE TO 00N125W IS 
DRY AND CLOUD FREE IN THE MIDDLE AND UPPER LEVELS. A PLUME OF 
UPPER LEVEL MOISTURE WITH SOME MULTI LEVEL CLOUDS IS MOVING 
ACROSS MEXICO NORTH OF 20N AND SOUTH OF THE MOISTURE PLUME 
MENTIONED IN THE FIRST PARAGRAPH. THIS MOISTURE IS ALSO 
EMANATING FROM DIFFLUENT UPPER FLOW TO THE SOUTHEAST OF THE 
LARGE TROUGH THAT IS OVER THE NORTHWESTERN PART OF THE AREA.

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 VERY 
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 NORTHEAST TO EAST WINDS IN AND WEST OF THE GULF OF PAPAGAYO 
OF 20 TO 25 KT WILL CONTINUE THROUGH THE NEXT SEVERAL DAYS. 

GAP NORTHERLY STORM FORCE WINDS IN THE GULF OF TEHUANTEPEC 
REGION WILL DIMINISH TO GALE DURING MONDAY AND FALL TO 20 TO 30 
KNOTS TUESDAY.

$$
LL