000
AXPZ20 KNHC 092144
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC WED JAN 09 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 
2100 UTC.

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

THE MONSOON TROUGH IS ALONG 08N78W TO 09N83W TO 07N92W. THE 
INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 07N92W TO 
08N120W TO 08N130W TO 06N140W. SCATTERED MODERATE CONVECTION IS 
FROM 07N TO 11N BETWEEN 124W AND 130W.

...DISCUSSION...

A DEEP UPPER LOW RESIDES NEAR THE BIG BEND OF TEXAS WITH AN 
ATTENDANT UPPER TROUGH STRETCHING FROM THE LOW OUTWARD ACROSS 
THE FAR WESTERN GULF OF MEXICO TO ACROSS CENTRAL MEXICO INTO THE 
WATERS NEAR 15N114W. MOISTURE IS BEING ADVECTED FROM THE TROPICS 
ALONG THE ITCZ TO THE NE AHEAD OF THIS TROUGH ACROSS SOUTHERN 
MEXICO AND THE GULF OF MEXICO. AN UPPER DIRTY RIDGE IS W OF THIS 
TROUGH EXTENDING FROM 32N126W THROUGH 20N125W TO 06N123W. 
MOISTURE IS STREAMING INTO THIS RIDGE AHEAD OF ANOTHER UPPER 
TROUGH WHICH ARCS INTO THE AREA FROM 20N140W TO 10N132W. 
ELSEWHERE ACROSS THE DISCUSSION WATERS MAINLY DRY AND STABLE AIR 
IS PRESENT.

AT THE SURFACE...BROAD RIDGING IS PRESENT FROM 30N140W THROUGH 
20N110W TO 13N104W. FRESH TO NEAR GALE FORCE TRADES ARE IN PLACE 
ACROSS THE W CENTRAL WATERS SW OF THE RIDGE AND N OF THE ITCZ... 
ALONG WITH SEAS UP TO 12 FT IN MIXED NE AND NW SWELL. A 
SURROUNDING AREA OF MIXED NE AND NW SWELL OF 8 FT OR GREATER 
ENCOMPASSES A LARGE PORTION OF THE DISCUSSION WATERS W OF 106W.

A VIGOROUS COLD FRONT WILL BE PUSHING INTO THE NW CORNER THIS 
EVENING...QUICKLY REACHING FROM 30N125W THROUGH 25N130W TO 
22N140W BY LATE TONIGHT. FRESH TO NEAR GALE FORCE NORTHERLY 
WINDS WILL FOLLOW THE FRONT ALONG WITH LONG PERIOD SEAS UP TO 
15-16 FT IN MIXED NE AND NW SWELL. NONE OF THE GLOBAL MODELS ARE 
EXPLICITLY CALLING FOR GALE CONDITIONS TO OCCUR BEHIND THE FRONT 
NOR DO ANY OF THE GFS ENSEMBLES. THE FRONT WILL EXTEND FROM 
30N116W TO 25N123W TO 20N133W WHILE WEAKENING BY THU AFTERNOON 
...THEN WILL DEGENERATE INTO A REMNANT SHEAR LINE BY FRI 
AFTERNOON AS IT MOVES ACROSS THE BAJA CALIFORNIA PENINSULA. THE 
FRESH TO STRONG WINDS WILL MERGE WITH THE AREA OF TRADES IN THE 
W CENTRAL WATERS DESCRIBED ABOVE AS THE FRONTAL BOUNDARY BECOMES 
DIFFUSE. WHILE THE NE TRADES SHOULD DIMINISH SOMEWHAT ON SAT... 
THEY ARE LIKELY TO BE AT FRESH TO STRONG LEVELS THROUGH THE 
MIDDLE OF NEXT WEEK.

ALSO...A TIGHT PRES GRADIENT WILL EXIST AHEAD OF THE FRONT IN 
THE FAR NORTHERN GULF OF CALIFORNIA WHERE SOUTHERLY WINDS ARE 
FORECAST TO BE 20-25 KT N OF 29N THU AFTERNOON...VEERING TO W-NW 
BEHIND THE FRONT AND INCREASING TO 30 KT LATE THU NIGHT. THE 
NORTHERLY WINDS BEHIND THE FRONT WILL THEN DIMINISH TO 20 KT OR 
LESS BY THE END OF THE WEEK INTO THE WEEKEND AS THE PRES 
GRADIENT RELAXES OVER NW MEXICO.

GAP WINDS...A WEAK GULF OF PAPAGAYO GAP WIND EVENT WILL 
RE-INITIALIZE LATE TONIGHT PERSISTING THROUGH THE END OF THE 
WEEK. AS IS TYPICAL...WINDS AND SEAS WILL BE LOWER DURING THE 
AFTERNOON AND EARLY EVENING HOURS. THE PAPAGAYO GAP WINDS SHOULD 
CONTINUE THROUGH SAT BEFORE DIMINISHING ON SUN.

MEANWHILE...NO SIGNIFICANT GULF OF TEHAUNTEPEC GAP WIND EVENTS 
ARE ANTICIPATED FOR THE NEXT SEVERAL DAYS.

$$
LEWITSKY