000
AXPZ20 KNHC 030338
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC TUE JAN 3 2012

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS 
BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND 
METEOROLOGICAL ANALYSIS.

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

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...MONSOON 
TROUGH EXTENDS FROM A 1008 MB LOW PRES CENTER THAT 
INTERMITTENTLY FORMS ALONG THE MONSOON TROUGH NEAR 05N78W AND 
CONTINUES W TO 08N85W...THEN TURNS SW TO 05N91W THEN W TO 
06N100W WHERE LOW LEVEL WINDS INDICATE A TRANSITION TO AN ITCZ 
WHICH CONTINUES W TO BEYOND 07N140W. SCATTERED MODERATE 
CONVECTION IS DISSIPATING WITHIN 30 NM EITHER SIDE OF A LINE  
FROM 06N77W TO 06N82W...AND DISSIPATING WITHIN 15 NM OF 
05N94W...DISSIPATING WITHIN 30 NM OF 06.5N107W...AND PERSISTING 
WITHIN 30 NM EITHER SIDE OF A OF LINE FROM 10N130W TO 06N138W. 

...DISCUSSION...
A LONG WAVE TROUGH IS APPROACHING THE WESTERN SEABOARD OF N 
AMERICA WITH AN EMBEDDED SHORTWAVE TROUGH EXTENDING FROM 32N127W 
TO 19N138W AND INTO AN UPPER CYCLONE CUTTING OF AT 16N137W. THE 
UPPER TROUGH IS ACCOMPANIED BY A 120 NM WIDE BAND OF VERY DRY 
UPPER AIR...BUT UPPER MOISTURE IS INDICATED WITHIN 150 NM OF THE 
CYCLONE. IMMEDIATELY TO THE W...AN UPPER RIDGE IS COLLAPSING SE 
WITH UPPER MOISTURE SPILLING SE OVER THE AREA N OF 29N W OF 
133W. THE ASSOCIATED SURFACE COLD FRONT HAS WEAKENED 
CONSIDERABLY OVER THE PAST 6 HOURS AND WILL BE OMITTED FROM THE 
HIGH SEAS FORECAST. HOWEVER...LONG PERIOD NW SWELLS ARE 
PROPAGATING SE ACROSS THE NW PORTION AND ARE MIXING WITH NE 
SWELL...AND DRIVING COMBINED SEA HEIGHTS UP TO ABOUT 17 FT. 
THESE LARGE SEAS WILL SUBSIDE TO ABOUT 11 FT BY THEY TIME THEY 
REACH THE NORTHERN BAJA CALIFORNIA PENINSULA LATE TUE NIGHT.    

AN UPPER ANTICYCLONE IS NEAR 09N100W WITH AN UPPER RIDGE 
EXTENDING N THROUGH 32N114W AND ACROSS WESTERN N AMERICA. 
UPPER DEBRIS MOISTURE IS NOTED WITHIN THE ANTICYCLONIC FLOW. 
SOME THIS MOISTURE IS MOVING OVER CALIFORNIA TO THE N OF 33N... 
WHILE ANOTHER PLUME CONTINUES E ACROSS CENTRAL OLD MEXICO S OF 
25N AND FANNING OUT OVER THE SOUTHERN GULF OF MEXICO.   

A SECOND LONGWAVE TROUGH IS MOVING ACROSS EASTERN N AMERICA AND 
CONTINUES S ACROSS THE EASTERN GULF OF MEXICO TO A BASE OVER THE 
TROPICAL PACIFIC JUST N OF THE GALAPAGOS ISLANDS. THE UPPER 
LEVELS APPEAR VERY DRY S OF 15N E OF 103W.

GULF OF TEHUANTEPEC...
NORTHERLY WINDS HAVE INCREASED TO A STORM STRENGTH IN THE GULF 
OF TEHUANTEPEC WITH LATEST GUIDANCE SUGGESTING THESE STORM 
CONDITIONS WILL PERSIST THROUGH TUE NIGHT. THE ASSOCIATED SEAS 
ARE FORECAST TO BUILD TO ABOUT 23 FT WITH N AND NE SWELL 
PROPAGATING S ACROSS THE WATERS BETWEEN 93W AND 113W WED.

GULF OF PAPAGAYO...
NE-E WINDS IN AND DOWNSTREAM OF THE GULF OF PAPAGAYO WILL SPREAD 
N TO THE GULF OF FONSECA WED AND INCREASE TO 20-30 KT LATE TUE. 
SEAS WILL BUILD TO ABOUT 14 FT NEAR 09N89W. WINDS WILL FURTHER 
INCREASE TO MINIMAL GALE SW OF THE GULF OF PAPAGAYO ON WED 
MORNING AND CONTINUE INTO WED AFTERNOON BEFORE DIMINISHING BELOW 
GALE FORCE BY SUNSET WED.
     
GULF OF PANAMA...
NW-N WINDS AT 20 TO 25 KT ARE FUNNELING S ACROSS PANAMA OVER THE 
WATERS N OF 05N BETWEEN 78W AND 81W INCLUDING THE WESTERN GULF 
OF PANAMA. EXPECT THESE N WINDS TO INCREASE TO 20-25 KT TUE 
NIGHT THEN DIMINISH TO 20 KT WED WHILE VEERING TO N-NE.  

$$
NELSON