000
AXPZ20 KNHC 022220
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC FRI JAN 02 2009

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 IS ALONG THE LINE...06N77W TO 
03N81W TO 05N87W TO 11N117W TO 10N134W TO 08N140W. SCATTERED 
MODERATE AND ISOLATED STRONG CONVECTION WAS OCCURRING FROM 08N 
TO 14N BETWEEN 132W AND 113W. 

...DISCUSSION...

MID TO UPPER LEVEL TROUGH/SHEAR AXIS EXTENDS FROM A CYCLONIC 
CIRCULATION OVER EXTREME NW MEXICO NEAR 28N110W...WEST 
SOUTHWESTWARD TO A SMALL AND WEAK CYCLONIC CIRCULATION NEAR 
25N127W...CONTINUING SW TO ANOTHER WEAK CIRCULATION NEAR 
22N134W. MODERATE TO STRONG SUBSIDENCE WAS NOTED WITHIN 120-180 
NM N OF THE TROUGH AXIS...AND 60 NM S OF THE TROUGH. A 
SHARPENING MID/UPPER LEVEL TROUGH WELL NW OF THE AREA IS FCST TO 
DIG SWD INTO THE NE PORTION OF THE AREA AND DRIVE A COLD FRONT 
INTO THE REGION LATE SAT WITH FRESHENING NW WINDS OF 20 KT 
BEHIND THE FRONT SAT NIGHT AND SUN. AT THE SURFACE...1028 MB 
HIGH PRES NW OF THE AREA NEAR 32N144W WITH ASSOCIATED SFC RIDGE 
EXTENDING SE THROUGH 27N130W TO 18N110W. THE MODERATE PRES 
GRADIENT S OF THE RIDGE IS MAINTAINING AN AREA OF MODERATE TO 
FRESH TRADES FROM 12N TO 22N...W OF 125W. TRADES MAY INCREASE 
SLIGHTLY TO NEAR 30 KT ALONG 140W BY SUN AS THE PRES GRADIENT 
TIGHTENS.     

A SERIES OF UPPER LEVEL TROUGHS AND RIDGES DOMINATE THE PATTERN 
OVER THE DEEP TROPICS. DIFLUENT ANTICYCLONIC FLOW AT THE UPPER 
LEVELS FROM 08N TO 20N BETWEEN 114W AND 128W WAS AIDING IN 
MAINTAINING DEEP CONVECTION IN THE VICINITY OF TWO LOW LEVEL 
EASTERLY WAVES...ONE ALONG 127W...AND THE OTHER ALONG 118W.  
STRONG UPPER LEVEL WSW WINDS ARE ADVECTING MID AND HIGH LEVEL 
CLOUDS AND MOISTURE FROM THIS REGION ENE ACROSS SRN BAJA 
CALIFORNIA AND ACROSS THE NORTHERN THIRD OF MEXICO.   

GAP WINDS...
A MORNING QUIKSCAT PASS REVEALED NLY WINDS OF 20-25 KT IN THE 
GULF OF TEHUANTEPEC. HOWEVER...SLY FLOW OCCURRING ACROSS THE 
WESTERN GULF OF MEXICO...AND COMPUTER MODEL GUIDANCE...SUGGEST 
WINDS WILL DROP BELOW 20 KT SHORTLY...LIKELY WITHIN THE NEXT 6 
HOURS. ELSEWHERE ACROSS THE REGION...N TO NE GAP WINDS OF 20 TO 
25 KT ARE EXPECTED TO CONTINUE ACROSS AND DOWNWIND OF THE GULF 
OF PAPAGAYO THROUGH THE NEXT 48 HOURS...AND GULF OF PANAMA FOR 
THE NEXT 24 HOURS...BEFORE SUBSIDING. 

$$
STRIPLING