000
AXPZ20 KNHC 212158
TWDEP 

TROPICAL WEATHER DISCUSSION     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC WED FEB 21 2007

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS 
BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND 
METEOROLOGICAL ANALYSIS.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2145 UTC.

...ITCZ...
ITCZ AXIS 3N78W 5N83W 4.5N90W 5N104W 6N111W 4.5N120W 4N132W 
3N140W. SCATTERED MODERATE WITHIN 90 NM OF AXIS FROM 127W TO 
135W. 

...DISCUSSION...

BROAD LONGWAVE TROUGH DOMINATES THE AREA N OF 1ON W OF 120W. 
AN EMBEDDED SHARP MID-UPPER LEVEL SHORTWAVE TROUGH IS DROPPING 
DOWN THE BACK SIDE OF THE MEAN TROUGH AND EXTENDS FROM 35N134W 
SW TO NEAR 30N140W. THE ASSOCIATED SURFACE FRONT IS JUST 
ENTERING THE FAR NW CORNER OF THE AREA AND IS ACCOMPANIED BY A 
120 NM WIDE BAND OF LOW MID LAYERED CLOUDS WITH ONLY ISOLATED 
SHOWERS POSSIBLE. ELSEWHERE AT THE SURFACE A 1024 MB SFC HIGH 
WAS NEAR 30N124W WITH ASSOCIATED RIDGE COVERING THE AREA N OF 
THE ITCZ AND W OF 110W. 

AXIS OF SUBTROPICAL JTST EXTENDS FROM 18N140W ENEWD THROUGH 
23N125W-CENTRAL BAJA CALIFORNIA TO NRN MEXICO. SATELLITE DERIVED 
WINDS INDICATED CORE SPEEDS OF 110-130 KT W OF 135W. JET WAS 
ADVECTING MOSTLY UPPER LEVEL MOISTURE FROM THE ITCZ NEWD AND 
WITHIN WITHIN 240 NM EITHER SIDE OF LINE FROM 14N135W NEWD TO 
25N112W/BAJA CALIFORNIA. STRONG UPPER LEVEL SUBSIDENCE WAS NOTED 
WITHIN 240 NM POLEWARD OF THE JET AXIS. 

A SMALL UPPER ANTICYCLONE IS NOTED NEAR 10N109W...AND IS 
SEPARATED FROM A MORE DOMINANT UPPER RIDGE THAT EXTENDS 
FROM AN EXPANSIVE ANTICYCLONE OVER CENTRAL AMERICA AND THE 
EXTREME W CARIBBEAN WESTWARD ACROSS THE TROPICAL E PAC ALONG 
12N/13N. A SMALL UPPER INVERTED TROUGH EXTENDS N ACROSS THE 
EQUATOR AT 101W TO NEAR 9N104W. STRONG UPPER LEVEL SUBSIDENCE
COVERED CENTRAL AMERICA AND EXTENDED WWD OVER THE PACIFIC E OF 
110W AND WAS SUPPRESSING ITCZ CONVECTION TO ISOLATED AT BEST 
OVER THE AREA. 
  
GAP WINDS...
A BROAD AREA OF LOW PRES OVER THE SW GULF OF MEXICO IS EXPECTED 
TO SHIFT EASTWARD TONIGHT. NLY WINDS W OF THE TROUGH AXIS WILL 
BRIDGE THROUGH THE ISTHMUS OF TEHUANTEPEC INTO THE E PAC WATERS 
JUST AFTER SUNRISE THU...AND PULSE AROUND 20-25 KT THROUGH FRI 
MORNING. BRISK ELY TRADES IN THE SW CARIBBEAN WILL CONTINUE TO 
BRIDGE W INTO THE GULF OF PAPAGAYO AT 20 TO 25 KT AND SWD INTO 
THE GULF OF PANAMA THROUGH FRI. IN ADDITION MODELS SUGGEST THAT 
THE CURRENT LIGHT WIND REGIME OVER THE SEAS OF CORTEZ WILL 
CONTINUE INTO FRI.

$$
COBB