000
AXPZ20 KNHC 120933
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC FRI DEC 12 2008

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

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0915 UTC.

...ITCZ...
ITCZ AXIS IS CENTERED ALONG 06N78W TO 07N102W TO 11N123W TO 
09N130W TO 06N140W. SCATTERED MODERATE CONVECTION IS WITHIN 150 
NM S OF AXIS E OF 91W. SCATTERED MODERATE TO STRONG CONVECTION 
IS FROM 06N-09N BETWEEN 95W-103W. NUMEROUS MODERATE/SCATTERED 
STRONG CONVECTION IS WITHIN 120 NM OF THE AXIS BETWEEN 
115W-119W. SCATTERED MODERATE CONVECTION IS WITHIN 300 NM N OF 
THE AXIS BETWEEN 122W-127W.

...DISCUSSION...

GAP WINDS...
NORTHERLY FLOW CONTINUES TO FUNNEL THROUGH THE GULF OF 
TEHUANTEPEC TONIGHT. A HIGH-RES QSCAT PASS JUST AFTER 00Z SHOWED 
CORE WINDS AS HIGH AS 55 KT. SHIP DDFD2 REPORTED 26 KT AT 06Z 
NEAR 12N97W...WHICH AGREES WELL WITH THE AVAILABLE SCATTEROMETER 
DATA. HOWEVER...WINDS HAVE LIKELY DIMINISHED SOME AS THE MAIN 
TRAJECTORY OF THE CAA HAS SHIFTED E OF THE GAP. WINDS WILL 
CONTINUE TO GRADUALLY DIMINISH...BUT REMAIN WITHIN GALE 
CRITERIA...OVER THE NEXT 24-36 HOURS AS HIGH PRES SLIDES E 
ACROSS THE SOUTHERN CONUS ALLOWING WINDS TO VEER E OVER THE GULF 
OF MEXICO. BY SUN...WINDS WILL QUICKLY DIMINISH AS RETURN FLOW 
SETS UP OVER THE WRN GULF OF MEXICO.

DESPITE THE LACK OF DATA...PAPAGAYO AND FONSECA GAP WINDS HAVE 
LIKELY BEGUN DUE TO THE TIGHT PRESSURE GRADIENT IN ASSOCIATION 
WITH THE LEADING COLD FRONT OVER E HONDURAS. THESE GAP 
WINDS...ESPECIALLY PAPAGAYO...ARE ANTICIPATED TO BLOW FOR THE 
NEXT COUPLE OF DAYS BUT SHOULD REMAIN BELOW WARNING CRITERIA.  

ELSEWHERE...
HIGHLY AMPLIFIED RIDGE/TROUGH PATTERN COVERS THE WRN PART OF THE 
DISCUSSION ZONE. THE UPPER TROUGH EXTENDS S FROM AN EMBEDDED 
UPPER LOW NEAR 30N127W. THIS LARGE SCALE FEATURE IS SHEARING 
CONVECTION IN THE ITCZ AND SPREADING MID-HIGH LEVEL MOISTURE  
FROM THE DEEP TROPICS NWD ACROSS BAJA CALIFORNIA...MAINLAND 
MEXICO AND THE SW CONUS. THIS TROUGH WILL BE FURTHER AMPLIFIED 
AS ENERGY RIDES OVER THE RIDGE TODAY AND SAT SUPPORTING A COLD 
FRONT WHICH IS EXPECTED TO MOVE OVER THE NE WATERS SAT NIGHT AND 
SUN. N WINDS WILL INCREASE TO 20-25 KT N OF THE FRONT AND LONG 
PERIOD N SWELL WILL FOLLOW.

A BELT OF 20-25 KT NE/E TRADES ARE OCCURRING FROM 11N-24N W OF 
123W ON THE SE PERIPHERY OF STRONG HIGH PRES IN THE 
MID-LATITUDES. THIS HIGH WILL WEAKEN OVER THE NEXT DAY OR TWO 
ALLOWING THE TRADES TO SLACKEN.

$$
CANGIALOSI