000
AXPZ20 KNHC 281515
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC FRI DEC 28 2007

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 
1500 UTC.
 
...ITCZ...
INTERTROPICAL CONVERGENCE ZONE IS ALONG THE LINE...6N77W 7N105W 
9N120W 6N130W 6N140W.
SCATTERED MODERATE CONVECTION IS WITHIN 50 NM OF THE FOLLOWING 
POINTS 6.8N79.2W AND 6.7N89W AND 9N121W.
SCATTERED MODERATE TO STRONG CONVECTION IS WITHIN 100 NM OF THE 
POINT 8.3N108.7W.

...DISCUSSION...
UPPER LEVELS...
MIDDLE AND UPPER LEVEL TROUGH IS BETWEEN THE LINE 22N140W 
19N130W 23N120W 24N110W 29N100W TO THE SOUTH OF THE TROUGH AND 
THE LINE 29N140W 28N110W 32N100W TO THE NORTH OF THE TROUGH. THE 
AREA IS DRY AND CLOUD FREE IN THE MIDDLE AND UPPER LEVELS. UPPER 
LEVEL MOISTURE AND MULTI LEVEL CLOUDS CONTINUE TO MOVE 
NORTHEASTWARD OVER CENTRAL MEXICO IN A 600 NM WIDE BAND SOUTH OF 
THE TROUGH.

A RIDGE IS EXTENDING EASTWARD ACROSS THE PACIFIC NORTH OF THE 
TROUGH. UPPER LEVEL MOISTURE IS OBSERVED IN THIS REGION BUT ONLY 
A FEW HIGH CLOUDS ARE NOTED.

A WEAK MAINLY UPPER LEVEL TROUGH EXTENDS ACROSS THE AREA SOUTH 
OF THE ITCZ.  THIS AREA IS DRY AND CLOUD FREE IN THE MIDDLE AND 
UPPER LEVELS.

WEAK RIDGE IS BETWEEN THE TWO TROUGHS.

EXCEPT FOR LOCALIZED ITCZ CONVECTION THE AREAS EAST OF A LINE 
23N98W TO THE ITCZ NEAR 105W IS DRY AND CLOUD FREE IN THE MIDDLE 
AND UPPER LEVELS.

SURFACE...
STRONG RIDGE IS NORTH OF THE ITCZ WEST OF 115W.  A STRONG 
PRESSURE GRADIENT IS ASSOCIATED WITH THE RIDGE AND TRADES OF 20 
TO 30 KNOTS AND SEAS 10 TO 15 FT ARE OVER THIS AREA.  ELSEWHERE 
WEAK TROUGH IS ANALYZED.

GAP WINDS TO ABOUT 20 KNOTS WILL CONTINUE FOR ANOTHER DAY OR SO 
IN AND DOWNSTREAM OF THE GULF OF PAPAGAYO.

EXTENDED OUTLOOK...A MAJOR WIND EVENT IS SETTING UP FOR THE GULF 
OF TEHUANTEPEC GAP IN THE WAKE OF A STRONG COLD FRONT IN THE 
GULF OF MEXICO TUESDAY EVENING.

NORTHWEST WINDS IN THE GULF OF CALIFORNIA WILL FLUCTUATE AROUND 
20 KT DURING THE NEXT 48 HOURS.

$$
LL