000
AXPZ20 KNHC 130321
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL 
0405 UTC FRI DEC 13 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...GALE FORCE WINDS IN THE 30-40 KT RANGE AND 
SEAS OF 10-16 FT CONTINUE. THESE CONDITIONS WILL PERSIST THROUGH 
EARLY FRI THEN SHOULD DIMINISH TO JUST BELOW GALE FORCE BY 24 
HOURS...THEN QUICKLY TO 20 KT OR LESS BY EARLY SAT. 

THE LONG DURATION OF THIS GALE WIND EVENT CONTINUES TO GENERATE 
AND SEND A PLUME OF NE SWELL WELL TO THE SW OF THE IMMEDIATE 
GULF OF TEHUANTEPEC AREA...WITH 8-11 FT SEAS FROM 06N TO 13N 
BETWEEN 94W AND 118W MIXING WITH LONGER PERIOD SW AND NW SWELLS. 
THIS AREA OF COMBINED SEAS WILL CONTINUE TO PROPAGATE TO THE 
W...MERGING WITH A NEW AREA OF 8-10 FT PRIMARILY NE SWELL WITHIN 
AN AREA BOUNDED BY A LINE FROM 25N132W TO 13N116W TO 10N120W TO 
21N136W TO 25N132W BY 36 HOURS...SHIFTING W BY 48 HOURS WHILE A 
NEW SET OF NW SWELL ARRIVES AND MERGES IN THE NW CORNER OF THE 
DISCUSSION WATERS.

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

THE MONSOON TROUGH EXTENDS FROM 08N78W TO 04N95W. THE ITCZ 
EXTENDS FROM 04N95W TO 10N121W...THEN RESUMES FROM 10N125W TO 
BEYOND 09N140W. SCATTERED MODERATE AND ISOLATED STRONG 
CONVECTION IS WITHIN 75 NM EITHER SIDE OF THE ITCZ BETWEEN 107W 
AND 110W. SCATTERED MODERATE CONVECTION IS WITHIN 180 NM N OF 
THE ITCZ BETWEEN 111W AND 117W...WITHIN 180 NM S OF THE ITCZ 
BETWEEN 111W AND 119W...AND WITHIN 60 NM N OF THE ITCZ BETWEEN 
126W AND 132W.

ALSO...SCATTERED MODERATE ISOLATED STRONG CONVECTION IS FROM 04N 
TO 06N E 80W...AND FROM 15N TO 17N BETWEEN 126W AND 129W.

...DISCUSSION... 

A WEAKENING STATIONARY FRONT LINGERS OVER THE NW CORNER OF THE 
DISCUSSION WATERS REACHING FROM 32N135W TO BEYOND 29N140W. 
ASSOCIATED SEAS OF 8 FT OR GREATER ARE LIKELY TO REMAIN JUST NW 
OF THE WATERS...AND THE FRONT WILL DEGENERATE INTO A TROUGH 
LATER TONIGHT...SHIFTING W OF 140W ON FRI.

1028 MB HIGH PRES NEAR 33N129W EXTENDS A BROAD RIDGE TO THE SE 
TO NEAR 20N110W. MEANWHILE A SURFACE TROUGH IS EMBEDDED IN THE 
ITCZ FROM 14N122W TO 09N123W. THE PRESSURE GRADIENT BETWEEN THE 
RIDGING...TROUGH...AND THE FRONT TO THE NW IS ENOUGH TO SUPPORT 
FRESH TRADE WINDS OVER THE CENTRAL WATERS FROM 13N TO 17N W OF 
135W WHERE 8-9 FT SEAS ARE ALSO OCCURRING. WINDS WILL DIMINISH 
TO MODERATE OVER THAT AREA BY EARLY FRI ALLOWING FOR SEAS TO 
SUBSIDE TO LESS THAN 8 FT.

GULF OF PAPAGAYO...WINDS WILL CONTINUE TO PULSE TO FRESH TO 
STRONG LEVELS MAINLY DURING THE LATE NIGHT AND EARLY MORNING 
HOURS THROUGH EARLY SAT DURING THE TIMING OF NOCTURNAL DRAINAGE 
FLOW OFF THE NEARBY LANDMASS.

GULF OF CALIFORNIA...FRESH TO STRONG NW-N WINDS ARE SPILLING OUT 
OF THE SOUTHERN GULF OF CALIFORNIA TO 21N WITH SEMI-PERMANENT 
TROUGHING OVER NW MEXICO E OF THE ABOVE MENTIONED RIDGING. WINDS 
WILL DIMINISH TO 20 KT OR LESS TONIGHT...WITH ANOTHER AND MORE 
SIGNIFICANT ROUND OF FRESH TO STRONG WINDS ACROSS THE ENTIRE 
GULF OF CALIFORNIA EXPECTED THIS WEEKEND AS BOTH THE RIDGING AND 
TROUGHING BECOME MORE PRONOUNCED.

$$
LEWITSKY