000
AXPZ20 KNHC 010949
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC WED DEC 01 2010

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 
0900 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE AXIS IS ANALYZED FROM 08N83W 
TO 06N90W TO LOW PRES NEAR 11N110W TO LOW PRES NEAR 09N119W TO 
07N140W. SCATTERED MODERATE TO STRONG CONVECTION IS NOTED WITHIN 
180 NM IN THE NW AND N QUADRANTS AND 90 NM IN THE S SEMICIRCLE 
OF THE SECOND LOW. SIMILAR CONVECTION IS NOTED FROM 10N TO 12N 
BETWEEN 115W AND 118W.

...DISCUSSION...

1028 MB HIGH PRES IS CENTERED JUST N OF THE AREA NEAR 33N125W 
AND IS DRIFTING S. A RIDGE AXIS EXTENDS FROM THE HIGH CENTER 
THROUGH 23N120W TO 16N110W. THIS HIGH WILL SETTLE S OF 30N 
DURING THE NEXT 48 HOURS AND WILL WEAKEN AS A COLD FRONT 
APPROACHES THE NW WATERS. STRONG SURFACE TROUGHING EXISTS ALONG 
THE E COAST OF THE GULF OF CALIFORNIA. A TIGHT PRES GRADIENT IS 
IN PLACE BETWEEN THE TROUGHING AND RIDGE WITH STRONG NORTHERLY
FLOW ACROSS THE ENTIRE GULF OF CALIFORNIA. A 0418 UTC ASCAT PASS 
TRAVERSED THE GULF WATERS AND THE ENHANCED EXPERIMENTAL COASTAL 
WIND VECTORS INDICATED A DENSE AREA OF 30 KT WIND BARBS OVER THE 
CENTRAL GULF. THUS HOISTED A GALE WARNING THROUGH 12 UTC DUE TO 
THE ASCAT LOW BIAS. RESULTANT SEAS ARE 8 TO 11 FT WHICH ARE 
SPILLING OUT S OF THE GULF TO 18N. WINDS ARE EXPECTED TO 
DIMINISH TO LESS THAN 20 KT BY 06 UTC THU AS THE RIDGE WEAKENS 
AND THE TROUGHING BEGINS TO DISSIPATE.

THE PRESSURE PATTERN DESCRIBED ABOVE IS ALSO PRODUCING 20 KT N 
WINDS W OF THE BAJA CALIFORNIA PENINSULA N OF 25N AND E OF 118W 
AS CAPTURED BY THE SAME ASCAT PASS. AN AREA OF 20 KT NE TO E 
TRADES EXISTS FROM 09N TO 21N W OF 120W WITH RESULTANT SEAS OF 8 
TO 10 FT WHICH ARE COMMINGLING WITH NW SWELL. THESE TRADES WILL 
DIMINISH TO LESS THAN 20 KT WITH SEAS SUBSIDING TO LESS THAN 8 
FT BY 00 UTC FRI. THE COLD FRONT WILL ENTER THE NW WATERS AROUND 
00 UTC THU REACHING FROM 30N129W TO 24N133W TO 20N140W BY 06 UTC 
FRI. NW WINDS OF 20 TO 25 KT WITH SEAS OF 8 TO 12 FT IN NW SWELL 
WILL ARRIVE BEHIND THE FRONT.

IN THE FAR SE PORTION OF THE AREA...SW MONSOONAL FLOW WILL 
INCREASE S OF PANAMA AND COSTA RICA AS LOW PRES LINGERS N OF 
PANAMA IN THE SW CARIBBEAN SEA. 20 KT FLOW WILL FEED INTO THE SW 
CARIBBEAN LOW BEGINNING AROUND 12 UTC WED THEN WILL PERSIST 
THROUGH AT LEAST 0600 UTC FRI.

TWO AREAS OF LOW PRES ARE EMBEDDED IN THE ITCZ. A WEAK 1012 MB 
LOW IS CENTERED NEAR 11N110W. A 0416 UTC ASCAT PASS INDICATED 10 
TO 15 KT WINDS N OF THE LOW. THE ASCAT PASS ALSO SHOWED 20 KT 
SOUTHERLY FLOW S OF THE LOW AND ITCZ ROUGHLY FROM 02N TO 08N 
BETWEEN 96W AND 112W WHICH WAS NOT CAPTURED BY MODEL GUIDANCE. 
EXPECT THE SOUTHERLY FLOW TO WEAKEN TO 10 TO 15 KT WITHIN THE 
NEXT 12 HOURS. NO SIGNIFICANT CONVECTION IS NOTED WITH THIS LOW. 
ANOTHER 1012 MB LOW IS CENTERED NEAR 09N119W. ASSOCIATED 
CONVECTION IS AS DESCRIBED IN THE ITCZ SECTION ABOVE. THIS LOW 
IS FORECAST TO DISSIPATE INTO AN OPEN TROUGH JUST BEYOND 48 
HOURS.

GAP WINDS...
A STRONG COLD FRONT HAS BLASTED THROUGH THE SW GULF OF MEXICO 
AND S OF THE GULF OF TEHUANTEPEC EARLY THIS MORNING. EXPECT 
STORM FORCE WINDS TO HAVE RECENTLY COMMENCED IN THE GULF OF 
TEHUANTEPEC AS STRONG NORTHERLY WINDS FUNNEL S THROUGH THE 
CHIVELAS PASS. WINDS WILL DIMINISH TO GALE FORCE BY 06 UTC THU 
WITH MODEL GUIDANCE NOW MAINTAINING MINIMAL GALE FORCE 
CONDITIONS THROUGH 48 HOURS.

FRESH TRADES IN THE SW CARIBBEAN SEA ARE FUNNELING INTO THE GULF 
OF PAPAGAYO. WINDS ARE EXPECTED TO INCREASE TO 20 TO 25 KT IN 
THE GULF OF PAPAGAYO AS LOW PRES LINGERS IN THE SW CARIBBEAN SEA 
THROUGH 24 HOURS WITH NEW LOW PRES DEVELOPING IN THE E PAC SW OF 
COSTA RICA BY 48 HOURS.

$$
LEWITSKY