000
AXPZ20 KNHC 231500
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL 
1605 UTC MON DEC 23 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

...SPECIAL FEATURES...

ATTENTION REMAINS FOCUSED ON THE UPCOMING GULF OF TEHUANTEPEC 
WIND EVENT...EXPECTED TO BE THE THIRD STORM FORCE WIND EVENT OF 
THE SEASON. THE COLD FRONT OVER THE GULF OF MEXICO HAS REACHED 
THE BAY OF CAMPECHE. COLD DENSE AIR BEHIND THE FRONT HAS STARTED 
TO FUNNEL THROUGH THE CHIVELA PASS INTO THE GULF OF TEHUANTEPEC. 
WINDS OVER THE GULF OF TEHUANTEPEC HAVE INCREASED TO NEAR GALE 
FORCE THIS MORNING. WINDS WILL INCREASE TO GALE FORCE THIS 
AFTERNOON...AND QUICKLY INCREASE TO STORM INTENSITY TONIGHT. 
SEAS WILL BUILD TO 10 FT BY THIS AFTERNOON...TO 15 FT THIS 
EVENING...17-19 FT TONIGHT AND REACH AS HIGH AS 18-20 FT BY TUE 
MORNING. FRESH TO STRONG WINDS WILL EXTEND WESTWARD TO REACH AS 
FAR AS 109W WITH SEAS TO 8 FT BY WED MORNING. WINDS ARE FORECAST 
TO DIMINISH BELOW STORM FORCE TUE AFTERNOON...THEN BELOW GALE 
FORCE WED.

PLEASE REFER TO THE LATEST NHC/TAFB HIGH SEAS FORECAST UNDER 
AWIPS/WMO HEADERS MIAHSFEP2/FZPN03 KNHC FOR MORE DETAILS.
 
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... 

THE MONSOON TROUGH EXTENDS FROM 09N84W TO 06N100W WHERE LOW 
LEVEL WINDS SUGGEST A TRANSITION TO ITCZ WHICH EXTENDS TO 
07N131W TO BEYOND 06N140W. SCATTERED MODERATE CONVECTION 
WAS NOTED WITHIN 120 NM N OF ITCZ BETWEEN 125W AND 135W. 

...DISCUSSION... 

HIGH PRESSURE OF 1034 MB IS CENTERED N OF THE AREA NEAR 39N133W 
WITH RIDGE EXTENDING SOUTHEASTWARD TO NEAR 20N111W. THE PRES 
GRADIENT BETWEEN THE RIDGE AND LOWER PRES IN THE VICINITY OF THE 
ITCZ IS PRODUCING A SMALL AREA OF FRESH TO STRONG TRADES FROM 
12N TO 16N W OF 125W. A TROUGH IS EXPECTED TO DEVELOP ALONG 132-
133W TONIGHT MAINTAINING A SMALL AREA OF FRESH TO STRONG WINDS 
OVER THIS AREA THROUGH WED MORNING.

LONG PERIOD NW SWELLS...WITH WAVE PERIODS BETWEEN 18-21 SEC 
ALONG THE LEADING EDGE COVER MUCH OF THE FORECAST WATERS W OF 
110W. THESE SWELLS WILL CONTINUE TO PROPAGATE EASTWARD COVERING 
MUCH OF THE DISCUSSION AREA W OF 100W BY TONIGHT. THIS SWELL 
EVENT WILL MIX WITH SEAS GENERATING DOWNSTREAM OF THE GULF OF 
TEHUANTEPEC BY TUE MORNING.  

WINDS WILL PULSE OVER THE NEXT COUPLE OF DAYS OVER THE GULF OF 
PAPAGAYO...PEAKING NEAR 25 KT DURING THE OVERNIGHT AND EARLY 
MORNING HOURS WITH THE ASSISTANCE OF THE NOCTURNAL DRAINAGE 
FLOW. SEAS WILL BUILD TO NEAR 8 FT DURING THE PERIOD OF 
STRONGEST WINDS. 

GULF OF CALIFORNIA...THE PRESSURE GRADIENT BETWEEN BUILDING HIGH 
PRESSURE OVER THE GREAT BASIN REGION AND TROUGHING OVER MEXICO 
IS SUPPORTING FRESH TO STRONG NW WINDS OVER THE GULF OF 
CALIFORNIA N OF 24N. HIGH PRESSURE OVER THE GREAT BASIN REGION 
WILL START TO WEAKEN TONIGHT RELAXING THE PRESSURE GRADIENT OVER 
THE GULF OF CALIFORNIA WITH WINDS DIMINISHING BELOW 25 KT BY 
EARLY TUE. 
 
$$
AL