000
AXPZ20 KNHC 052205
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC FRI DEC 05 2008

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

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0315 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE IS CENTERED ALONG 5N78W 7N88W
6N100W 8N115W 10N127W 7N140W. SCATTERED MODERATE/ISOLATED STRONG 
CONVECTION IS WITHIN 120 NM S OF THE AXIS BETWEEN 102W-107W... 
AND ALSO FROM 8N-15N BETWEEN 125W-130W. SCATTERED MODERATE 
CONVECTION IS WITHIN 60 NM OF THE AXIS BETWEEN 120W-122W. 

...DISCUSSION...

A LARGE UPPER TROUGH CONTINUES TO EXTEND WSW FROM CALIFORNIA TO 
28N129W TO SW OF THE AREA AT 19140W. WITHIN THIS TROUGH...WATER
VAPOR IMAGERY SHOWS A SERIES OF EMBEDDED UPPER LEVEL LOWS. THE 
FIRST IS RATHER WEAK AND ELONGATED IS LOCATED NEAR 32N120W...THE
SECOND IS ABOUT 4-5 DEG IN DIAMETER MOVING W 20 KT NEAR 28N134W
...AND THE THIRD APPEARING RATHER ELONGATED NEAR 19N139W. THE 
TROUGH WILL QUICKLY SHIFT TO THE ERN UNITED STATES ON SAT AS A 
HIGHLY AMPLIFIED RIDGE TO THE NW OF THE TROUGH SPILLS EASTWARD. 
THE FIRST OF THE UPPER LOWS WILL MEANDER OFF THE SOUTHERN 
CALIFORNIA COAST THROUGH SAT...THEN MOVE SE TOWARDS NORTHERN 
BAJA CALIFORNIA LATE SUN NIGHT INTO EARLY MON AND BECOME 
ABSORBED INTO A MID/UPPER TROUGH THAT CARVES SWD OVER THE 
WESTERN UNITED STATES. THE SECOND UPPER LEVEL LOW WILL DROP SW 
OVER THE NEXT 24 HOURS AND ABSORBED THE THIRD LOW. QUIKSCAT DATA 
FROM NEAR 1500 UTC THIS MORNING SHOWED WHAT APPEARS TO BE THE 
BEGINNINGS OF A WEAK SURFACE TROUGH...A REFLECTION
OF THE UPPER LOW NEAR 28N134W...EXTENDING FROM 26N134W NW TO 
32N140W. GLOBAL MODEL GUIDANCE SUGGESTS THAT THIS TROUGH WILL 
LINGER OVER THE NW PORTION OF THE AREA THROUGH EARLY NEXT WEEK 
RESULTING IN AN AREA OF TIGHT PRES GRADIENT OVER THAT PORTION OF 
THE AREA AS IT INTERACTS WITH HIGH PRES RIDGING THAT STRENGTHENS 
AS IT BUILDS SE INTO THE NORTHERN AND CENTRAL PORTIONS OF THE 
AREA.  

ELSEWHERE OVER THE AREA...BROAD MID/UPPER LEVEL RIDGING IS 
OBSERVED WITH A POCKET OF UPPER LEVEL DIFFLUENCE FROM 7N TO 17N 
BETWEEN 115W AND 130W. WITHIN THIS POCKET...PATCHES OF RAIN WITH 
EMBEDDED SCATTERED MODERATE TO STRONG TSTMS CONTINUE TO BE 
NOTED. UPPER LEVEL MODEL GUIDANCE INDICATES THAT THIS ACTIVE 
AREA OF PRECIPITATION SHOULD LAST UNTIL THE UPPER LOW NEAR 
28N134W LIFTS NE AND WEAKENS BY THE MIDDLE OF NEXT WEEK.

PRESENT GULF OF TEHUANTEPEC GALE EVENT OF WINDS OF 25-35 KT IS
FORECAST TO END SAT AFTERNOON AS HIGH PRES OVER MEXICO WEAKENS
RELAXING THE PRES GRADIENT ALONG SE MEXICO AND THE GULF.

ACROSS THE GULF OF PAPAGAYO...NE WINDS OF 20-25 KT WERE NOTED BY 
QUIKSCAT DATA FROM AROUND 1130 UTC THIS MORNING. THESE WINDS ARE 
EXPECTED TO LAST THROUGH EARLY NEXT WEEK AND BE AT THEIR MAXIMUM
INTENSITY IN THE MORNINGS. DOWNWIND OF THE GULF OF 
PAPAGAYO...QUIKSCAT DATA ALSO CONFIRMED THE PRESENCE OF A SWATH 
OF NE 20 KT WINDS FROM 8N-13N BETWEEN 92W-105WW SURFACE RIDGING 
ACROSS THE CENTRAL AMERICA WILL BE ENHANCED SOME OVER THE NEXT 
24-48 HOURS BY THE SAME HIGH PRES THAT AFFECTED THE GULF OF 
TEHUANTEPEC WINDS. THIS WILL ALLOW FOR THIS AREA OF WINDS TO 
TRANSLATE WESTWARD TO NEAR 125W IN ABOUT 48 HOURS.

LATEST NOAA WAVEWATCH GUIDANCE SUGGESTS THAT SEAS WILL PEAK UP 
TO 10 FT IN THE GULF OF TEHUANTEPEC. NE SWELL WILL LIKELY SPREAD 
W FROM THE GULF OVER THE NEXT DAY OR TWO BEFORE DECAYING FURTHER.

ELSEWHERE...NE WINDS TO 20 KT ARE NOTED IN QUIKSCAT DATA TO COVER
THE AREA N OF 8N AND W OF 130W...HOWEVER THE MAIN IMPACT IN THAT
AREA CONTINUES TO BE NW SWELL OF 8-11 FT. THESE SWELLS SHOULD
SLOWLY SUBSIDE THROUGH SAT...BUT REMAIN HIGH OVER THE NW PART
INTO EARLY NEXT WEEK.

$$
AGUIRRE