000
AXPZ20 KNHC 100332
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC TUE FEB 10 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 
0200 UTC.

...ITCZ...
THE INTERTROPICAL CONVERGENCE ZONE LIES ALONG A LINE FROM 04N77W 
TO 00N95W TO 03N118W TO 05N135W TO 05N140W. SCATTERED MODERATE 
CONVECTION CAN BE FOUND WITHIN 180 NM N AND 90 NM S OF THE ITCZ 
AXIS W OF 122W.

...DISCUSSION...
THE UPPER TO MID LEVEL PATTERN WILL BE PROGRESSIVE AND SOMEWHAT 
AMPLIFIED OVER N WATERS THE NEXT FEW DAYS.  THE MEAN TROUGH OVER 
NE WATERS IS CURRENTLY BEING RELOADED WITH NORTHERN STREAM 
ENERGY.  THIS TROUGH WILL CONTINUE EASTWARD AS IT DIGS SOUTH 
INTO NW MEXICO OVERNIGHT TONIGHT.  THE SURFACE COLD FRONT 
ASSOCIATED WITH THIS TROUGH IS CURRENTLY MOVING THROUGH NE 
WATERS AND NORTHERN BAJA CALIFORNIA.  SOUTHWEST WINDS AHEAD OF 
THE FRONT WERE UP TO 30 KT IN THE NORTHERN GULF OF CALIFORNIA 
ACCORDING TO THE ASCAT PASS AT 1742 UTC.  THIS FRONT IS EXPECTED 
TO WEAKEN AS IT MOVES SOUTH THROUGH THE SIERRA MADRE 
OCCIDENTAL.  WINDS AROUND 20 KT ARE EXPECTED TO SHIFT S OF 
28N IN THE GULF OF CALIFORNIA TUE AFTERNOON THROUGH WED AS A 
RESULT.

THE WESTERLY UPPER JET MAX ALONG 24N W OF 125W WILL SHIFT 
EASTWARD OVER NIGHT TONIGHT...OVERTAKEN BY THE TROUGHING OVER 
THE SW U.S. AND NW MEXICO.  HOWEVER...WESTERLY FLOW WILL 
CONTINUE TO DOMINATE WATERS N OF 20N...SHEARING THE UPPER LOW 
CURRENTLY JUST NW OF FORECAST WATERS...AND AGAIN INCREASE AHEAD 
OF THE NEXT DEEP LAYER MID LATITUDE TROUGH EXPECTED TO MOVE INTO 
N WATERS BY WED.  THE STRONG WESTERLY FLOW ALOFT WILL LIMIT THE 
DEVELOPMENT OF DEEP CONVECTION N OF 20N THE NEXT FEW DAYS...BUT 
WILL PROPEL MID TO UPPER LEVEL MOISTURE EASTWARD AND GENERATE 
HIGH CLOUDS.

SCATTERED MODERATE CONVECTION CAN BE FOUND WITHIN 180 NM N AND 
90 NM S OF THE ITCZ AXIS W OF 122W.  THIS CONVECTION IS 
SUPPORTED BY UPPER LEVEL DIFFLUENCE OVER THIS REGION WHERE THE 
WESTERLY JET SPLITS...TAKING THE SUBTROPICAL JET CORE ON A 
SOUTHWARD TURN S OF THE WEAK ANTICYCLONE CENTERED NEAR 05N115W 
WHILE SOME OF THE WESTERLY FLOW IS DIRECTED N OF THE 
ANTICYCLONE...JOINING THE STRONG WESTERLY FLOW OVER N WATERS.  
CONVECTION IS LIKELY TO PERSIST IN THIS REGION AS THE UPPER 
LEVEL FLOW IS EXPECTED TO REMAIN LARGELY DIFFLUENT BETWEEN THE 
EQUATOR AND 10N W OF 115W FOR THE NEXT FEW DAYS.  

GAP WINDS...THE MID LATITUDE PATTERN WILL BE TOO PROGRESSIVE TO 
INDUCE ANOTHER TEHUANTEPEC EVENT WITHIN THE NEXT TWO DAYS.  
FARTHER SOUTH...THE 1606 ASCAT PASS SHOWS WINDS TO 25 KT 
DOWNWIND OF THE GULF OF PAPAGAYO.  SHIP OBSERVATION ZCDG4 
REPORTED 26 KT NEAR 11N87W AT 0000 UTC...CONFIRMING THE EARLIER 
ASCAT WINDS.  WINDS SHOULD BEGIN TO DIMINISH BY TUE AFTERNOON AS 
PRESSURES LOWER OVER THE WESTERN GULF OF MEXICO AND CARIBBEAN 
UNDER THIS PROGRESSIVE MID LATITUDE PATTERN...BUT THEY ARE NOT 
EXPECTED TO FALL BELOW 20 KT OVER THE NEXT TWO DAYS.  
MEANWHILE...THE WINDS OFF WESTERN PANAMA...WHICH WERE AT 20 TO 
25 KT ACCORDING TO THE 1426 ASCAT PASS...SHOULD DROP BELOW 20 KT 
OVERNIGHT TUE NIGHT AS THE WINDS IN THE SW CARIBBEAN DIMINISH.

$$
SCHAUER CLARK