000
AXPZ20 KNHC 010931
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0900 UTC.

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

THE MONSOON TROUGH EXTENDS FROM 07N78W TO 08N86W TO 06N102W TO 
10N109W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 
10N116W TO 05N140W. NO SIGNIFICANT CONVECTION NOTED. HOWEVER...A 
SURFACE TROUGH IS EMBEDDED WITHIN THE ITCZ AND IS ANALYZED FROM 
10N113W TO 15N111W. SCATTERED MODERATE CONVECTION IS OCCURRING 
FROM 11N TO 20N BETWEEN 105W AND 116W WITH THIS FEATURE.

...DISCUSSION...

A SHARP LONG WAVE UPPER LEVEL TROUGH EXTENDS FROM THE NORTHERN 
PLAINS STATES...TO OVER THE NORTHERN BAJA CALIFORNIA...TO A BASE 
NEAR 11N121W. MIDDLE TO UPPER LEVEL DIVERGENCE ALOFT ON THE 
SOUTHEASTERN PERIPHERY OF THIS FEATURE CONTINUES TO SUPPORT AN 
AREA OF SCATTERED SHOWERS AND WIDELY SCATTERED TSTMS OVER THE 
AREA FROM 11N TO 20N BETWEEN 105W AND 116W AS THE UPPER 
TROUGHING MOVES EAST. A SURFACE TROUGH ASSOCIATED WITH THE UPPER 
LEVEL TROUGH IS ANALYZED FROM 10N113W TO 15N111W AND REMAINS 
EMBEDDED WITHIN THE MONSOON TROUGH/ITCZ AXIS. THIS IS 
INTERACTING WITH 1029 MB HIGH CENTERED NEAR 31N132W WHICH IS 
MAINTAINING A BROAD WEDGE SHAPED AREA OF 20 TO 25 KT TRADE WINDS 
ACROSS THE E PACIFIC FROM ROUGHLY 10N TO 22N W OF 110W. SEAS IN 
THIS AREA ARE 8 TO 13 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 21N W OF 123W. BY LATE TUESDAY...FRESH TO STRONG 
SOUTHWESTERLIES WILL PRECEDE A COLD FRONT APPROACHING THE FAR NW 
CORNER OF THE DISCUSSION AREA...BUT DIMINISH THROUGH WEDNESDAY 
AS THE FRONT SHIFTS EASTWARD. THIS WILL ALSO WEAKEN THE HIGH 
PRESSURE CURRENTLY ALONG 30N...ALLOWING THE AREA OF TRADE WINDS 
OVER THE DEEP TROPICS TO SHRINK IN SIZE FROM THE EAST. 

GULF OF TEHUANTEPEC...GLOBAL MODELS SUGGEST THE NEXT GALE EVENT 
FOR THE GULF OF TEHUANTEPEC WILL START THURSDAY AND LAST THROUGH 
SATURDAY AS STRONG SURFACE RIDGING BUILDS SOUTHWARD ALONG THE 
EASTERN MEXICO COAST.

GULF OF PAPAGAYO...SIMILARLY STRONG AND PERSISTENT GAP FLOW 
THROUGH THE GULF OF PAPAGAYO WILL START TO DIMINISH THROUGH 
TUESDAY. NE TO E SWELL FROM THESE EVENTS WILL PERSIST FOR 
ANOTHER COUPLE OF DAYS FROM GENERALLY 07N TO 13N BETWEEN 92W AND 
102W...MIXING WITH NW SWELL W OF 100W BY LATE TUESDAY.

GULF OF CALIFORNIA...HIGH PRESSURE BUILDING OVER THE GREAT BASIN 
ALONG WITH LOW PRESSURE OVER NORTH-CENTRAL MEXICO WILL ALLOW NW 
WINDS TO INCREASE TO 20 TO 25 KT OVER MUCH OF THE GULF OF 
CALIFORNIA LATER TODAY...PERSISTING THROUGH EARLY THURSDAY.

$$
HUFFMAN