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Eastern Pacific Tropical Weather Discussion (Text)

000
AXPZ20 KNHC 120341
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL 
0405 UTC THU DEC 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.

...SPECIAL FEATURES...

GULF OF TEHUANTEPEC...N TO NE 30 TO 40 KT GALE FORCE WINDS 
CONTINUE TO SPREAD THROUGH THE GULF OF TEHUANTEPEC. WINDS ARE 
FORECAST TO INCREASE UP TO 45 KT DURING THE LATE NIGHT/EARLY 
MORNING HOURS TONIGHT WITH THE AIDE OF NOCTURNAL DRAINAGE FLOW 
THEN WILL DIMINISH SLIGHTLY BACK TO 30 TO 35 KT DURING THE DAY 
THU. EXPECT ANOTHER INCREASE BACK TO 40 KT OVERNIGHT THU 
NIGHT... DIMINISHING BELOW GALE FORCE BY 48 HOURS. THE LONG 
DURATION OF THESE WINDS WILL SEND A PLUME OF NE SWELL TO THE SW-
W WELL AWAY FROM THE GULF OF TEHUANTEPEC...REACHING TO 115W BY 
48 HOURS. MEANWHILE SIGNIFICANT WAVE HEIGHTS WILL PEAK AT 10 TO 
17 FT DURING THE TIME OF THE STRONGEST WINDS.

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

THE MONSOON TROUGH EXTENDS FROM 08N78W TO 04N87W. THE ITCZ 
EXTENDS FROM 09N115W TO BEYOND 08N140W. SCATTERED MODERATE AND 
ISOLATED STRONG CONVECTION IS WITHIN 120 NM N OF THE ITCZ 
BETWEEN 110W AND 116W...WITHIN 90 NM S OF THE ITCZ BETWEEN 115W 
AND 118W...AND FROM 10N TO 12N BETWEEN 120W AND 124W. SCATTERED 
MODERATE CONVECTION FROM 09N TO 15N W OF 130W.

...DISCUSSION... 

A COLD FRONT IS JUST NW OF THE AREA. MODEL GUIDANCE DOES MANAGE 
TO MOVE IT JUST INTO THE NW CORNER EARLY THU BEFORE STALLING OUT 
LATER THU...THEN SHIFTING BACK W OF 140W AS A REMNANT TROUGH 
SHORTLY THEREAFTER. SEAS TO 8 FT IN NW SWELL WILL TOUCH 30N140W 
BUT WILL LIKELY REMAIN JUST OUTSIDE THE DISCUSSION WATERS. 

WEAKENING 1024 MB HIGH PRES IS AHEAD OF THE FRONT NEAR 34N130W 
WITH A BROAD RIDGE EXTENDING TO THE SE ACROSS THE DISCUSSION 
AREA THROUGH 32N125W TO 14N106W. THE PRESSURE GRADIENT BETWEEN 
THE RIDGING AND LOWER PRESSURES ALONG THE ITCZ IS TIGHT ENOUGH 
TO SUPPORT FRESH TRADES OVER THE W CENTRAL WATERS. NE WIND WAVES 
COMBINED WITH LONGER PERIOD NW SWELL IS RESULTING IN 8-9 FT SEAS 
W OF A LINE FROM 21N140W TO 15N128W TO 09N140W. THESE SEAS WILL 
GRADUALLY SUBSIDE TO LESS THAN 8 FT BY FRI AFTERNOON AS THE NW 
SWELL DECAYS.

TO THE SE OF THE HIGH/RIDGING...SEMI-PERMANENT TROUGHING OVER NW 
MEXICO WILL INDUCE FRESH WINDS IN THE SOUTHERN GULF OF 
CALIFORNIA SPILLING S TO 20N. CURRENTLY MODEL GUIDANCE KEEPS 
WINDS NO HIGHER THAN 20 KT AND SEAS JUST LESS THAN 8 FT... 
ALTHOUGH ISOLATED STRONG WINDS CANNOT BE RULED OUT.

GULF OF PAPAGAYO...WINDS WILL INCREASE TO FRESH TO STRONG WITHIN 
60 NM EITHER SIDE OF A LINE FROM 11N86W TO 09N89W BY THU NIGHT 
INTO EARLY FRI AS TRADE WINDS IN THE WESTERN CARIBBEAN SEA 
INCREASE...THEN WILL DIMINISH TO 20 KT OR LESS BY LATE FRI 
AFTERNOON.

$$
LEWITSKY