000
AXPZ20 KNHC 010354
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC TUE JAN 01 2013

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 
0300 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS FROM 06N77W TO 08N85W TO 08105W. THE 
ITCZ CONTINUES FROM 10N117W TO 06N140W. SCATTERED MODERATE TO 
ISOLATED STRONG CONVECTION IS NOTED WITHIN 150 NM EITHER SIDE OF 
A TROUGH EXTENDING FROM 15N110W TO 10N115W. SCATTERED MODERATE 
CONVECTION IS ALSO NOTED FROM 09N TO 11N BETWEEN 95W AND 100W.

...DISCUSSION...

A SHARP LONG WAVE UPPER TROUGH EXTENDS FROM THE NORTHERN PLAINS 
STATES...ACROSS NORTHERN BAJA CALIFORNIA...TO NEAR 10N125W. 
UPPER DIVERGENCE ALOFT ON THE SE SIDE OF THIS FEATURE HAS BEEN 
SUPPORTING CLUSTERS OF SHOWERS AND THUNDERSTORMS FOR THE PAST 
SEVERAL DAYS AS THE UPPER TROUGH PUSHES EAST. A SURFACE TROUGH 
ASSOCIATED WITH THE UPPER TROUGH APPEARS TO BE FORMING ALONG 
110W N OF THE MONSOON TROUGH/ITCZ AXIS. THIS IS INTERACTING WITH 
1029 MB HIGH PRES CENTERED NEAR 30N130W TO MAINTAIN A BROAD 
WEDGE SHAPED AREA OF 20 TO 25 KT TRADE WINDS ACROSS THE E 
PACIFIC FROM ROUGHLY 10N TO 20N W OF 110W. SEAS IN THIS AREA ARE 
8 TO 12 FT IN FRESH NE WIND WAVES MIXING WITH LONGER PERIOD NW 
SWELL THAT COVERS MOST OF THE AREA W OF 110W. 

A SECOND ROUND OF NW SWELL CONTINUES TO PUSH INTO THE AREA 
COVERING N OF 22N W OF 135W. BY LATE TUE...FRESH TO STRONG SW 
WILL PRECEDE A COLD FRONT APPROACHING THE FAR NW CORNER OF THE 
DISCUSSION AREA...BUT DIMINISH THROUGH WED AS THE FRONT SHIFTS 
E. THIS WILL ALSO WEAKEN THE HIGH PRES CURRENTLY ALONG 
30N...ALLOWING THE AREA OF TRADE WINDS OVER THE DEEP TROPICS TO 
SHRINK IN SIZE FROM THE EAST. 

GULF OF TEHUANTEPEC...WINDS OVER THE GULF OF TEHUANTEPEC HAVE 
DIMINISHED BELOW GALE FORCE...AND WILL CONTINUE TO RAPIDLY 
DIMINISH AS HIGH PRES N OF THE AREA WEAKENS AND SHIFTS EAST. 
LOOKING AHEAD...GLOBAL MODELS SUGGEST THAT THE NEXT GALE EVENT 
THROUGH THE GULF OF TEHUANTEPEC WILL START THU NIGHT AND LAST 
THROUGH SAT.

GULF OF PAPAGAYO...SIMILARLY STRONG AND PERSISTENT GAP FLOW 
THROUGH THE GULF OF PAPAGAYO WILL START TO DIMINISH THROUGH TUE. 
NE TO E SWELL FROM THESE EVENTS WILL PERSIST FOR ANOTHER COUPLE 
OF DAYS FROM GENERALLY 05N TO 12N BETWEEN 95W AND 110W...MIXING 
WITH NW SWELL W OF 105W BY TUE.

GULF OF CALIFORNIA...HIGH PRES BUILDING OVER THE GREAT BASIN 
ALONG WITH LOW PRES OVER N CENTRAL MEXICO WILL ALLOW NW WINDS TO 
INCREASE TO 20 TO 25 KT OVER MUCH OF THE GULF OF CALIFORNIA 
STARTING TOMORROW...PERSISTING THROUGH EARLY THU.

$$
CHRISTENSEN