000
AXPZ20 KNHC 111617
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC FRI JAN 11 2008

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

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1600 UTC.
 
...ITCZ...
INTERTROPICAL CONVERGENCE ZONE...7N78W 6N90W 5N100W 6N110W 7N120W
6N130W 5N140W. SCATTERED MODERATE CONVECTION IS WITHIN 30 NM 
EITHER SIDE OF THE AXIS BETWEEN 119W-122W...AND ALSO WITHIN 30 
NM S OF THE AXIS BETWEEN 127W-129W.

...DISCUSSION...
MID/UPPER TROUGH EXTENDS FROM NW MEXICO SW THROUGH 21N113W...THEN
W TO 22N117W TO NEAR 22N122W AND SW TO A VERY PRONOUNCED 
STATIONARY MID/UPPER LEVEL CYCLONIC CIRCULATION LOCATED NEAR 
14N131W. MID/UPPER LEVEL RIDGING IS PRESENT N OF BOTH THE TROUGH 
AND CYCLONIC CIRCULATION. THE COMBINATION OF THESE FEATURES IS 
RESULTING IN MODERATE SUBSIDENCE AND ASSOCIATED DRY AIR TO BE 
CHANNELED SWD INTO THE TROPICAL BELT W OF ABOUT 135W AND AROUND 
AND INTO THE CYCLONIC CIRCULATION. DIVERGENCE PRESENT TO THE E 
OF THE CYCLONIC CIRCULATION CONTINUES TO PRODUCE AN AREA OF 
OVERCAST MULTILAYERED CLOUDS WITH SCATTERED SHOWERS AND 
OCCASIONAL ISOLATED TSTMS ALONG AND WITHIN 120 NM N OF THE ITCZ 
BETWEEN 119W-122W PRIMARILY DUE TO DIVERGENCE ALOFT E OF THE 
CIRCULATION. THE CYCLONIC CIRCULATION IS FORECAST TO BEGIN TO 
DIP S IN ABOUT 24-36 HRS. TO THE E...A MID/UPPER LEVEL
TROUGH IS EVIDENT ALONG 3N84W 7N89W 10N97W 12N103W. MODERATE 
SUBSIDENCE SURROUNDING THE TROUGH IS INHIBITING AND SIGNIFICANT 
CONVECTION FROM DEVELOPING E OF 100W INCLUDING ALONG THE ITCZ. 
UPPER LEVEL RIDGING EXTENDS NW FROM S AMERICA TO ACROSS CENTRAL 
AMERICA AND SE MEXICO...ALSO KEEPING CONVECTION THERE TO A 
MINIMUM.

AT THE SURFACE...A STATIONARY 1026 MB HIGH CENTER IS ANALYZED 
NEAR 31N131W WITH AN ASSOCIATED RIDGE SE THROUGH 26N124W TO 
19N119W. HIGH PRES COVERS THE REGION N OF 15N AND W OF 117W WITH 
GENERALLY MODERATE TRADES FROM 5N-20N W OF 122W. N WINDS ARE 
FORECAST TO INCREASE THROUGH THE GULF OF TEHUANTEPEC ON SUN AS 
HIGH PRES RIDGING BUILDS S OVER MEXICO. NLY WINDS MAY ALSO 
INCREASE ACROSS THE GULF OF CALIFORNIA LATE SAT INTO EARLY NEXT 
WEEK AS THIS SAME RIDGE INTERACTS WITH LOW PRES TROUGHING ALONG 
THE W COAST OF MEXICO INTO SRN CALIFORNIA. CONVECTION SHOULD 
CONTINUE TO BE FAIRLY ACTIVE E OF THE MID/UPPER CIRCULATION TO 
ABOUT 120W...INCLUDING THE ITCZ THROUGH SUN. 

MEANWHILE...WAVEWATCH III MODEL GUIDANCE IS CONSISTENT IN 
SHOWING ANOTHER GROUP OF LARGE NW SWELL ENTERING THE NW PORTION 
OF THE AREA BEGINNING THIS AFTERNOON...AND SPREADING EASTWARD N 
OF MAINLY N OF 20N THROUGH SUN WHILE DIMINISHING SOME.

AGUIRRE