000
AXPZ20 KNHC 121504
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SAT JAN 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
THE MONSOON TROUGH EXTENDS FROM 08N82W TO 05N95W WHERE LOW LEVEL 
WINDS SUGGEST A TRANSITION TO ITCZ WHICH EXTENDS TO 07N110W TO 
BEYOND 07N140W. SCATTERED MODERATE CONVECTION WAS NOTED FROM 08N 
TO 11N W OF 130W.

...DISCUSSION...

SHORT WAVE ENERGY IS ROUNDING THE BASE OF A MID TO UPPER LEVEL 
TROUGH EXTENDING FROM THE NORTHERN ROCKIES THROUGH SOUTHERN 
ARIZONA. ASSOCIATED SURFACE TROUGHING WILL MAINTAIN FRESH NW TO 
N FLOW ALONG THE COAST OF NORTHERN BAJA TODAY BEFORE DIMINISHING 
TONIGHT. THE SURGE IN NW WINDS WILL BE ACCOMPANIED BY A PUSH OF 
NW SWELL UP TO 13 FT N OF 25N E OF 125W. 

STRONG STATIONARY 1041 MB HIGH PRES IS CENTERED NEAR 39N141W 
WITH RIDGE EXTENDING SE TO NEAR 21N114W. THE STRENGTH OF THIS 
HIGH PRES CENTER COMBINED WITH LOWER PRESSURE IN THE VICINITY OF 
THE ITCZ IS MAINTAINING A TIGHT PRES GRADIENT. THIS IS 
SUPPORTING FRESH TO STRONG TRADES OVER MUCH OF THE AREA N OF THE 
ITCZ AND W OF 110W...AS CONFIRMED BY THE LATEST SCATTEROMETER 
DATA.

GULF OF CALIFORNIA...THE SURFACE RIDGE WILL BUILD FURTHER 
EASTWARD THROUGH SOUTHERN BAJA TONIGHT FOLLOWING THE PASSAGE OF 
THE MID LEVEL SHORT WAVE TROUGH. THIS WILL RESULT IN NORTHERLY 
WINDS BRIEFLY INCREASING TO 20 TO 25 KT OVER THE SOUTHERN GULF 
OF CALIFORNIA LATE TONIGHT...BEFORE DIMINISHING SUN MORNING. 
LOOKING AHEAD...STRONG HIGH PRES WILL BUILD OVER THE GREAT BASIN 
EARLY NEXT WEEK WHICH WILL RESULT IN STRONG TO NEAR GALE NW 
WINDS DOWN THE LENGTH OF THE GULF OF CALIFORNIA BY LATE MON.

GAP WINDS...THE GULF OF PAPAGAYO CONTINUES TO PULSE WITH FRESH 
TO STRONG WINDS DURING THE LATE NIGHT AND EARLY MORNING HOURS 
DIMINISHING TO 20 KT OR LESS DURING THE AFTERNOON HOURS. EXPECT 
THE WINDS TO STRENGTHEN ONCE AGAIN TONIGHT INTO EARLY SUNDAY 
BEFORE DIMINISHING TO 20 KT OR LESS BY SUN AFTERNOON. 

LOOKING AHEAD FOR THE GULF OF TEHUANTEPEC...A SURGE OF COLD AIR 
IS FORECAST TO ARRIVE BEHIND A COLD FRONT IN THE GULF OF MEXICO 
LATE TUE INTO WED. NORTHERLY WINDS WILL BE FUNNELED THROUGH THE 
CHIVELA PASS ACROSS THE GULF OF TEHUANTEPEC AREA...WITH GALE 
FORCE WINDS POSSIBLE BY MIDWEEK.

$$
AL