000
AXPZ20 KNHC 232145
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC WED FEB 23 2011

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

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2100 UTC.

...ITCZ...
THE INTERTROPICAL CONVERGENCE ZONE AXIS IS ANALYZED FROM 1010 MB 
LOW PRES NEAR 04N79W TO 06N86W TO 01N100W TO 05N120W TO 05N140W. 
SCATTERED MODERATE CONVECTION FROM 02N TO 05N E OF 80W.    

...DISCUSSION...

ALOFT...AN UPPER LEVEL TROUGH ENTERS THE AREA NEAR 30N120W THEN 
EXTENDS SW OVER HE N WATERS TO NEAR 26N135W. A 90-120 KT JET 
STREAM BRANCH IS SE OF THE UPPER LEVEL TROUGH AND CROSSES 
CENTRAL BAJA CALIFORNIA AND NW MEXICO INTO THE SW CONUS. AN 
ANTICYCLONIC CIRCULATION S OF THE GULF OF TEHUANTEPEC NEAR 
09N100W WILL MIGRATE N TO THE COAST BY THU. STRONG SUBSIDENCE 
ACCOMPANIES THIS FEATURE AS EVIDENCED IN RECENT WATER VAPOR 
IMAGERY. A RIDGE EXTENDS NE FROM THE ANTICYCLONE OVER SE MEXICO 
AND N CENTRAL AMERICA INTO THE WESTERN CARIBBEAN WITH ANOTHER 
RIDGE EXTENDING S TO THE EQUATOR AT 104W. AN INVERTED UPPER 
LEVEL TROUGH IS OFF THE COAST OF COLOMBIA E OF 85W S OF 10N. 
THIS TROUGH IS SUPPORTING A SURFACE TROUGH EXTENDING FROM 7N77W 
TO 2N79W. 

AT THE SURFACE...A WEAK 1018 MB LOW IS CENTERED NEAR 25N122W. A 
COLD FRONT EXTENDS FROM THE LOW TO TO 27N118W TO 22N120W TO 
21N128W. BOTH THE 1746 UTC ASCAT PASS AND THE 1540 UTC WINDSAT 
PASS SHOWED N TO NE WINDS OF 20 KT W OF THE FRONT. MAXIMUM SEA 
HEIGHTS OF 12 FT IN NW SWELL FOLLOW THE FRONT. THE LOW PRES AND 
COLD FRONT WILL DISSIPATE IN ABOUT 24 HOURS. 

THE PRES GRADIENT BETWEEN THE ANOMALOUSLY SOUTHERN ITCZ AND THE 
RIDGING N OF IT IS MAINTAINING FRESH TRADE WINDS AS FAR S AS 
05N. THIS AREA OF TRADES IS EXPECTED TO EXPAND EASTWARD WHEN THE 
SURFACE RIDGING TO THE N BUILDS EASTWARD AS THE COLD FRONT AND 
LOW PRES SYSTEM OVER NE WATERS DISSIPATES. WINDS ARE ALSO 
EXPECTED TO INCREASE TO 20 KT ACROSS THE SOUTHERN PORTION OF THE 
GULF OF CALIFORNIA AND JUST W OF THE BAJA CALIFORNIA PENINSULA 
AS PRES GRADIENT TIGHTENS BETWEEN THE RIDGE AND DEEPENING LOW 
PRES OVER NE MEXICO. THE NEXT COLD FRONT WILL REACH THE FAR N 
WATERS BY FRI NIGHT.

GAP WINDS...
GULF OF PAPAGAYO...NE WINDS OF 20 KT CONTINUE TO FUNNEL THROUGH 
THE GULF OF PAPAGAYO. THIS FLOW WILL CONTINUE TO PULSE OVER THE 
NEXT FEW DAYS...ESPECIALLY IN THE EARLY MORNING HOURS WHEN 
DRAINAGE FLOW FROM LAND IS AT A MAXIMUM.

$$
GR