000
AXPZ20 KNHC 120340
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC TUE FEB 12 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...
MONSOON TROUGH FROM 00N80W TO 06N92W TO 06N100W THEN ITCZ AXIS 
TO 04N108W TO 07N122W TO 05N129W TO 06N132W THEN CONTINUES FROM 
05N134W TO 04N140W.  NO SIGNIFICANT CONVECTION. 

...DISCUSSION...
UPPER LEVEL TROUGH FROM DEEP LAYER CYCLONE IN CENTRAL ROCKIES 
ACROSS NORTHERN BAJA CALIFORNIA...THEN SW TO 28N128W TO 32N135W. 
SHARP RIDGE CREST EMERGES ALONG 32N138W FROM UPPER LEVEL 
ANTICYCLONE AT 09N130W.  RIDGE BLOCKS EASTERN INTRUSION OF WELL 
STACKED DEEP LAYER CYCLONE WHICH THEN DROPS S FROM 30N144W 
SUPPORTING A SURFACE LOW PRES CENTER AT 31N145W AND COLD FRONT 
THAT EXTEND TO 30N142W TO 24N145W.  MODEL GUIDANCE SOLUTIONS 
WEAKENS CYCLONE QUICKLY AND OPENS IT INTO A TROUGH LATE WED 
EFFECTIVELY STALLING FRONT JUST W OF 140W.  WHILE NOT FEELING 
THE FULL IMPACT OF LOW PRES CENTER NOR ITS ASSOCIATED FRONT...NW 
CORNER OF BASIN IS EXPECTED TO SEE AN INCREASE IN SE WIND SPEEDS 
WITH CONFUSED SEAS BUILDING TO 12-13 FT IN SE WAVES AND LARGE NW 
SWELLS.

SECOND ANTICYCLONE...THIS ONE OVER HONDURAS...PROVIDES MOIST 
TROPICAL MOISTURE TO MONSOON TROUGH E OF 101W WHILE REMAINING  
REGION E OF 130W REMAINS VERY DRY AND STABLE.  

...ELSEWHERE AT THE LOWER LEVELS...
VIGOROUS HIGH PRES CENTER 1035 MB WELL N OF AREA BUILDS RIDGE SE 
TO 13N97W.  LARGE LONG PERIOD NW SWELL PROPAGATE ACROSS BASIN W 
OF 110W REACHING AS FAR S AS THE EQUATOR BY END OF PERIOD.  PRES 
GRADIENT S OF RIDGE ENOUGH TO SUPPORT MODERATE TO FRESH NE 
BREEZE ACROSS BASIN N OF ITCZ W OF 110W.

STRENGTHENING SURFACE TROUGH ALONG CENTRAL MEXICO ENHANCES FRESH 
TO STRONG NW WINDS OVER GULF OF CALIFORNIA LATE TUE WITH 
FUNNELING SEAS REACHING 9 FT IN SOUTHERN FRINGES OF GULF BY END 
OF FORECAST PERIOD. 

GAP WINDS...
GULF OF PAPAGAYO...INCREASED NE TRADES THROUGH CENTRAL AMERICA 
ENHANCE FRESH TO STRONG BREEZE IN GULF OF PAPAGAYO.  WINDS PULSE 
BETWEEN STRONG BREEZE THROUGH EARLY MORNINGS...WHEN DRAINAGE 
FLOW OFF MOUNTAINS IS AT A MAXIMUM...TO A FRESH BREEZE WHEN THE 
SEABREEZE COUNTERS EASTERLIES.  SEAS BUILD UP TO 8 FT WITH 
STRONG WINDS.  POSSIBLE WEAKENING OF TRADES LATE WED MAY 
DIMINISH WINDS BEYOND FORECAST PERIOD.  

$
WALLY BARNES