000
AXPZ20 KNHC 302150
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC WED JAN 30 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 09N83W TO 05N96W. THE INTERTROPICAL 
CONVERGENCE ZONE AXIS EXTENDS FROM 05N96W TO 06N120W TO 05N130W 
TO 06N140W. SCATTERED MODERATE CONVECTION IS WITHIN 120 NM N OF 
THE ITCZ BETWEEN 111W AND 126W.

...DISCUSSION...

NEARLY STATIONARY STRONG 1038 MB HIGH PRES IS CENTERED N OF THE 
AREA NEAR 39N133W WITH ASSOCIATED RIDGE EXTENDING OVER THE 
FORECAST WATERS THROUGH 32N130W TO NEAR 12N103W. THE PRES 
GRADIENT SW OF THE RIDGE AND LOWER PRES IN THE VICINITY OF THE 
ITCZ IS MAINTAINING FRESH TO STRONG TRADES OVER MUCH OF THE W 
CENTRAL PORTION OF THE FORECAST AREA...AS CONFIRMED BY RECENT 
SCATTEROMETER DATA. THE HIGH PRES AND ATTENDANT RIDGE IS 
FORECAST TO WEAKEN DURING THE NEXT 24-48 HOURS AND AS A RESULT 
THE AREAL COVERAGE OF THE TRADE WINDS WILL SIGNIFICANTLY 
DECREASE. 

THE PRES GRADIENT BETWEEN THE RIDGE AND TROUGHING OVER WESTERN 
MEXICO IS RESULTING IN FRESH TO STRONG WINDS IN THE GULF OF 
CALIFORNIA S OF 28N AS CAPTURED BY A RECENT ASCAT PASS. SEAS OF 
8-9 FT ARE SPILLING OUT OF THE MOUTH OF THE GULF TO 17N BETWEEN 
106W AND 110W. HIGH PRES WILL CONTINUE TO BUILD ACROSS THE U.S. 
GREAT BASIN REGION TONIGHT WITH BROAD TROUGHING INCREASING OVER 
MEXICO. THIS WILL EXPAND THE STRONG WINDS TO THE ENTIRE GULF S 
OF 30N. THE AREA OF HIGH PRES WILL THEN WEAKEN THU RELAXING THE 
PRES GRADIENT WITH WINDS DIMINISHING TO 20 KT OR LESS BY EARLY 
FRI MORNING.

GAP WINDS...
GULF OF TEHUANTEPEC...A STRONG COLD FRONT CURRENTLY EXTENDING 
FROM SOUTHERN ALABAMA TO VERACRUZ MEXICO WILL RAPIDLY SHIFT 
EASTWARD ACROSS THE REMAINDER OF THE GULF OF MEXICO...PUSHING E 
OF THE BAY OF CAMPECHE LATE TONIGHT. A DENSER AIR MASS BEHIND 
THIS FRONT WILL FUNNEL THROUGH THE CHIVELA PASS INTO THE GULF OF 
TEHUANTEPEC. WINDS WILL RAPIDLY RAMP UP TO GALE FORCE BY 06 UTC 
THU...AND STRONG GALE FORCE BY 12-18 UTC THU. STRONG HIGH PRES 
BUILDING BEHIND THE FRONT OVER EASTERN MEXICO AND THE WESTERN 
GULF OF MEXICO WILL HELP TO MAINTAIN THESE CONDITIONS THROUGH 
FRI AFTERNOON. ALL THE GLOBAL MODELS AND THE NAM REGIONAL MODEL 
SUGGEST WINDS IN THE 30-45 KT RANGE...HOWEVER IT IS NOT OUT OF 
THE QUESTION THAT MINIMAL STORM FORCE WINDS (925 MB WINDS AND 
30M GUIDANCE WINDS ARE UP TO 50-55 KT) WHICH WILL NEED TO BE 
MONITORED IN CASE THE WARNING NEEDS TO BE UPGRADED PRIOR TO THE 
EVENT. ALL MODELS ARE IN AGREEMENT SHOWING THIS EVENT PEAKING 
BETWEEN 1200-1800 UTC THU...WITH RESULTANT SEAS BUILDING TO UP 
TO 18 FT.

GULF OF PAPAGAYO...FRESH TO STRONG WINDS WILL DEVELOP IN THIS 
AREA BY EARLY THU MORNING. THE STRONGEST WINDS WILL OCCUR DURING 
THE LATE NIGHT AND EARLY MORNING HOURS WITH THE ADDED COMPONENT 
OF NOCTURNAL DRAINAGE FLOW...AND WEAKER WINDS DURING THE 
AFTERNOON AND EARLY EVENING HOURS. A LARGER AREA OF THESE WINDS 
WILL BE PRESENT FRI WITH SEAS BUILDING TO UP TO 10 FT JUST 
DOWNWIND OF THE GULF.

GULF OF PANAMA...FRESH TO STRONG WINDS WILL SPREAD ACROSS THE 
ISTHMUS OF PANAMA FROM THE SW CARIBBEAN SEA TO THE GULF OF 
PANAMA BY THU NIGHT THROUGH FRI. SEAS WILL BUILD TO UP TO 9 FT 
DOWNWIND OF THE GULF BY FRI AFTERNOON.

$$
LEWITSKY