000
AXPZ20 KNHC 150948
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC SUN DEC 15 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0945 UTC.

...SPECIAL FEATURES...

GULF OF CALIFORNIA...A TIGHT PRESSURE GRADIENT WILL MAINTAIN 
MINIMAL GALE CONDITIONS THIS MORNING WITHIN ABOUT 45 NM OF COAST 
OF BAJA CALIFORNIA PENINSULA FROM 25-31N...WITH MAXIMUM SEAS OF 
11 FT. THE AREA OF GALE WINDS WILL SHRINK BY EARLY THIS 
AFTERNOON TO ACROSS THE WATERS TO THE N OF 30N WITHIN 45 NM OF 
THE COAST OF BAJA CALIFORNIA PENINSULA. THE GALE CONDITIONS WILL 
DIMINISH BY SUNSET TODAY. NORTHERLY WINDS AT 20-30 KT WINDS WITH 
SEAS OF 5-8 FT...WILL CONTINUE ELSEWHERE ACROSS THE GULF OF 
CALIFORNIA AND EXTEND S FROM THE GULF TO ALONG 19N...ALL TO THE 
E OF 109W. NW-N 20-25 KT WINDS ARE EXPECTED IN THE CABO 
CORRIENTES AREA AS WELL. N-NE 15-25 KT WINDS WILL ALSO FUNNEL 
THROUGH NORTHERN BAJA CALIFORNIA PENINSULA GAPS...ROUGHLY WITHIN 
45 NM EITHER SIDE OF A LINE FROM 29N115W TO 27N116W...WITH SEAS 
BUILDING TO 8 FT TODAY. THE GRADIENT WILL RELAX LATE TONIGHT 
INTO MON WITH NW WINDS AT 10-15 KT THROUGHOUT THE GULF OF 
CALIFORNIA BY LATE MON. 
 
GULF OF TEHUANTEPEC...STRONG NORTHERLY WINDS ARE CURRENTLY 
PROGRESSING S ACROSS THE SW GULF OF MEXICO...IN ASSOCIATION WITH 
A RAPIDLY MOVING COLD FRONT...AND WILL SURGE THROUGH THE CHEVILA 
PASS AT MINIMUM GALE FORCE BY SUNRISE THIS MORNING. THE 
NORTHERLY WINDS WILL RAPIDLY INCREASE TO MINIMAL STORM FORCE OF 
40-50 KT BY THIS AFTERNOON...WITH MAXIMUM SEAS OF 21 FT NEAR 
13.5N96W LATE TONIGHT. THE STORM CONDITIONS WILL CONTINUE 
THROUGH SUNRISE ON MON...WITH STRONG GALE WINDS OF 35-45 KT 
PERSISTING ON MON AFTERNOON. THE GRADIENT WILL GRADUALLY WEAKEN 
ON TUE AND WED WITH MINIMAL GALE WINDS EXPECTED THROUGH THE 
NOCTURNAL MAXIMUM LATE WED NIGHT. WINDS SHOULD QUICKLY DIMINISH 
TO 10-15 KT BY EARLY THU NIGHT.  

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

THE MONSOON TROUGH EXTENDS W ACROSS THE SW CARIBBEAN FROM THE 
COLOMBIAN COAST AT 09N76W TO ACROSS COSTA RICA ALONG 10N TO THE 
PACIFIC COAST OF COSTA RICA AT 10N85W...THEN DIPS SW TO 06N97W 
...THEN TURNS W TO 06N107W...THEN NW TO 09N117W THEN W TO 
08N122W WHERE SCATTEROMETER WINDS INDICATE A TRANSITION TO AN 
ITCZ. THE ITCZ THEN CONTINUES WESTWARD TO BEYOND 08N140W. 

SCATTERED MODERATE ISOLATED STRONG CONVECTION IS NOTED S OF THE 
MONSOON TROUGH WITHIN 30 NM EITHER SIDE OF LINE FROM 05N79W TO 
08N83W. ISOLATED MODERATE TO STRONG CONVECTION IS OBSERVED ALONG 
THE MONSOON TROUGH WITHIN 30 NM EITHER SIDE OF A LINE FROM 
08N90W TO 07N108W. SCATTERED MODERATE ISOLATED STRONG CONVECTION 
IS NOTED ALONG THE MONSOON TROUGH AND ITCZ WITHIN 60 NM OF A 
CLUSTER AT 07N116W AND WITHIN 30 NM OF A CLUSTER AT 09N125W. 
SIMILAR CONVECTION CONTINUES N OF THE MONSOON TROUGH FROM 09-14N 
BETWEEN 113-122W WHERE AN INTERMITTENT SURFACE TROUGH APPEARS IN 
THE SCATTEROMETER DATA. 
  
...DISCUSSION... 

A SURFACE RIDGE EXTENDS FROM 32N134W TO 17N104W. THE PRESSURE 
GRADIENT IS SUPPORTING NE 15-20 KT TRADES FROM 10-28N TO THE W 
OF 115W. LONG PERIOD NW SWELL IS MIXING WITH THE ASSOCIATED NE 
TRADE WIND SWELL...AND ALSO WITH LONG PERIOD CROSS-EQUATORIAL 
SOUTHERLY SWELL...RESULTING IN COMBINED SEAS OF 7-10 FT WITHIN 
THIS AREA OF ENHANCED TRADES. THE NW SWELLS ARE EXPECTED TO 
BEGIN TO SUBSIDE TONIGHT AS THE PRESSURE GRADIENT ALSO RELAXES. 
THE AREA OF NE 15-20 KT WINDS WILL BE CONFINED ACROSS THE 
DISCUSSION WATERS FROM 08-21N TO THE W OF 120W BY TUE MORNING... 
THEN SHIFTING W ON WED. 
       
GULF OF PAPAGAYO...NE-E WINDS ARE EXPECTED TO BEGIN TO PULSE AT 
20-25 KT DURING THE MAXIMUM NOCTURNAL DRAINAGE TONIGHT. THIS 
PATTERN IS EXPECT TO REPEAT EACH NIGHT THROUGH THU NIGHT. 
 
$$
NELSON