000
AXPZ20 KNHC 022220
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC WED JAN 02 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2130 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
MONSOON TROUGH FROM 06N77W TO 09N110W.  ITCZ AXIS FROM 10N115W 
TO 06N130W TO 05N140W.  ISOLATED MODERATE CONVECTION WITHIN 60 
NM OF MONSOON TROUGH AXIS E OF 86W.

...DISCUSSION...
BROAD MID TO UPPER LEVEL RIDGE OVER WESTERN HALF OF BASIN ABLE 
TO HOLD ITS GROUND AGAINST DEEP LAYER TROUGH APPROACHING FROM 
THE W.  UPPER LEVEL CYCLONE SUPPORTING TROUGH SHIFT NE ALLOWING 
RIDGE TO STALL TROUGH AND ITS ATTENDANT COLD FRONT IN NW CORNER 
OF BASIN.  

SECOND LARGE AMPLITUDE UPPER LEVEL TROUGH WITH CYCLONE OVER 
ARIZONA DIGS INTO E PAC TO 12N104W.  AREA OF UPPER LEVEL 
DIVERGENT FLOW E OF TROUGH ENHANCING SCATTERED CONVECTION FROM 
12N TO 15N BETWEEN 99W AND 102W. 

...ELSEWHERE AT THE LOWER LEVELS... 
HIGH PRES CENTER 1023 MB AT 27N129W WEAKENING AND IS EXPECTED 
TO DISSIPATE BY LATE THU OR FRI.  COLD FRONT LOSES ITS UPPER 
LEVEL SUPPORT AND STALLS FROM 30N129W TO 24N140W FRI WITH ITS 
FRESH NW WINDS DIMINISHING BELOW 20 KT BUT BRINGING IN LARGE 
LONG PERIOD NW SWELL UP TO 14 FT WHICH WILL SPREAD SE TO REACH 
EQUATOR W OF 110W BY LATE FRI.  FRESH NE TRADES EXPECTED TO 
DIMINISH IN AREA BY FRI AS HIGH PRES WEAKENS. 

WEAKENING HIGH PRES ALSO LOOSENS PRES GRADIENT ENOUGH TO REDUCE 
AREA OF FRESH NW WINDS OVER GULF OF CALIFORNIA RESTRICTING THEM 
TO N OF 28N BY FRI.

GAP WINDS...
GULF OF TEHUANTEPEC...NEXT GALE EVENT EXPECTED TO START LATE 
TONIGHT REACHING GALE FORCE WINDS BY EARLY FRI THEN PERSIST 
THROUGH WEEKEND.

$$
WALLY BARNES