000
AXPZ20 KNHC 040950
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC TUE DEC 04 2007

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 
0945 UTC.
 
...ITCZ...
INTERTROPICAL CONVERGENCE ZONE IS ALONG THE LINE 5N77W 6N90W 
6N110W 7N127W 5N140W. SCATTERED MODERATE ISOLATED STRONG WITHIN 
90-120 NM OF THE AXIS BETWEEN 110W AND 118W. WIDELY SCATTERED 
MODERATE WITHIN 60 NM OF THE AXIS BETWEEN 88W AND 110W.

SCATTERED MODERATE CONVECTION WITHIN 60 NM OF 15.5N 100.5W.

...DISCUSSION...
BROAD DEEP LAYER TROUGH COVERS THE CENTRAL PACIFIC WELL NW OF 
THE AREA. A NARROW MID TO UPPER LEVEL RIDGE AXIS WAS E OF THE 
BROAD TROUGH WITH AXIS ALONG 32N131W SWWD TO NEAR 22N140W. 
FURTHER E...AN UPPER LEVEL ANTICYCLONE WAS NEAR 20N119W AND 
DOMINATED THE FLOW OVER THE AREA FROM 15N TO 25N BETWEEN 100W 
AND 128W. A NARROW UPPER LEVEL TROUGH AXIS WAS NOTED BETWEEN THE 
TWO AREAS OF ANTICYCLONIC FLOW WITH AN AXIS ALONG 32N127W 
THROUGH SSWWD TO AN UPPER LEVEL CYCLONIC CIRCULATION/LOW NEAR 
15N135W THEN CONTINUING SE TO NEAR TO 9N131W. 

ANOTHER UPPER LOW IS IN THE DEEP TROPICS NEAR 5N117W WITH UPPER 
TROUGH AXIS EXTENDING NWD TO 12N116W. A NARROW CHANNEL OF SE 
UPPER LEVEL FLOW IS NOTED BETWEEN THIS UPPER TROUGH...THE UPPER 
CYCLONIC CIRCULATION/LOW TO THE W AND ANTICYCLONE TO THE N 
DRAWING TROPICAL MOISTURE NWWD TO 25N BETWEEN 120W AND 130W.

FURTHER N...AN UPPER LEVEL SHEAR/TROUGH AXIS FROM SE TEXAS 
ACROSS NRN MEXICO TO NRN BAJA CALIFORNIA WITH STRONG SUBSIDENCE 
IN ITS WAKE WAS SWEEPING SWD AT 15 KT AND WAS IMPINGING UPON
THE ANTICYCLONE NEAR 20N119W.   

AT THE SURFACE...A STATIONARY FRONT ALONG 32N134W TO 28N140W 
WAS BECOMING INCREASINGLY ILL-DEFINED WITH ONLY MODEST 
SHOWER ACTIVITY WITHIN 60-90 NM E OF THE FRONT. RIDGE COVERS THE 
REMAINDER OF THE AREA N OF 14N BETWEEN BAJA CALIFORNIA AND THE 
STATIONARY FRONT WITH A 1031 MB CENTER NEAR 31N124W. 

A 0050 UTC HIGH RESOLUTION QUIKSCAT PASS INDICATED MARGINAL GALE 
FORCE WINDS WERE OCCURRING WITHIN 60-75 NM OF THE GULF OF 
TEHUANTEPEC. THESE WINDS WERE LIKELY AT THEIR PEAK WITH NWP 
MODELS FORECASTING WINDS TO DROP TO 20 TO 25 KT WITHIN 24 HOURS 
AND TO LESS THAN 20 KT BY 36 HOURS. THE SAME PASS MISSED THE
GULF OF PAPAGAYO HOWEVER WINDS OF NEAR 20 KT ARE EXPECTED OVER 
THE NEXT 18-24 HOURS. 

A RARE HIGH RESOLUTION QUIKSCAT PASS AT 0226 UTC INDICATED NW 
WINDS OF 30 KT OVER THE N PORTION OF THE GULF OF CALIFORNIA. 
THESE WINDS ARE EXPECTED TO SUBSIDE TO LESS THAN 20 KT WITHIN 
24 HOURS. 

LARGE NORTHWEST SWELLS OF UP TO 27 FT OBSERVED OVER THE 
NORTHWEST PART OF THE AREA WILL SPREAD SOUTHEAST THROUGH 48 
HOURS AND IMPACT MOST OF THE AREA NORTH OF THE EQUATOR
AND WEST OF 115W. 

$$
COBB