000
AXPZ20 KNHC 100303
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL 
0405 UTC TUE DEC 10 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 CALIFORNIA GALE...THE PRESSURE GRADIENT BETWEEN STRONG 
1042 MB HIGH PRESSURE OVER THE GREAT BASIN REGION AND TROUGHING 
OVER MEXICO IS PRODUCING GALE FORCE WINDS OVER THE FAR NORTHERN 
PART OF THE GULF OF CALIFORNIA. HIGH PRESSURE OVER THE GREAT 
BASIN REGION WILL WEAKEN OVER THE NEXT 24-30 HOURS. AS A 
RESULT...WINDS ARE EXPECTED TO DIMINISH BELOW GALE FORCE BY TUE 
AFTERNOON...AND FURTHER DIMINISH BELOW 25 KT BY LATE TUE NIGHT.

GULF OF TEHUANTEPEC GALE...A STRONG COLD FRONT WILL MOVE THROUGH 
THE WESTERN GULF OF MEXICO ON TUESDAY. COOL DENSE AIR BEHIND THE 
FRONT WILL FUNNEL THROUGH THE CHIVELA PASS INTO THE GULF OF 
TEHUANTEPEC BY TUE AFTERNOON WITH WINDS INCREASING RAPIDLY TO 
NEAR GALE FORCE. WINDS WILL FURTHER INCREASE TO GALE FORCE BY 
TUE NIGHT. THE STRONG HIGH PRESSURE N OF THE AREA RESULTING FROM 
THE COOL DENSE AIR WILL ALLOW THE GALE FORCE WINDS IN THE GULF 
OF TEHUANTEPEC TO PERSIST INTO FRIDAY...WITH STRONGER CONDITIONS 
REACHING JUST BELOW STORM FORCE DURING THE OVERNIGHT AND EARLY 
HOURS WITH THE ADDED COMPONENT OF NOCTURNAL DRAINAGE FLOW. THE 
PERSISTENT GAP WIND FLOW WILL ALSO PRODUCE A PLUME OF SHORT 
PERIOD NE SWELL IN EXCESS OF 8 FT REACHING AS FAR WEST AS 110W 
BY LATE THURSDAY. 

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

THE MONSOON TROUGH EXTENDS FROM 09N84W TO 07N98W WHERE LOW LEVEL 
WINDS SUGGEST A TRANSITION TO ITCZ WHICH EXTENDS TO 08N118W TO 
BEYOND 05N140W. SCATTERED MODERATE CONVECTION WAS NOTED WITHIN 
150 NM N OF ITCZ BETWEEN 125W AND 135W.

...DISCUSSION... 

LOW PRESSURE OF 1019 MB IS CENTERED OVER THE N PART OF THE AREA 
NEAR 28N127W WITH ASSOCIATED COLD FRONT EXTENDING OVER THE AREA 
FROM 30N123W TO 25N126W TO 26N137W. THE PRESSURE GRADIENT 
BETWEEN THE LOW AND 1038 MB HIGH PRESSURE CENTERED NEAR 44N133W 
IS PRODUCING AN AREA OF FRESH TO STRONG WINDS N OF THE FRONT 
WITH SEAS TO 11 FT IN NW SWELL. THE LOW AND FRONT ARE FORECAST 
TO DISSIPATE BY TUE WITH WINDS AND SEAS BEHIND THE FRONT 
DECREASING THROUGH WED. 

WEAK SURFACE RIDGING ALONG 23N IS SUPPORTING FRESH TO STRONG 
TRADES FROM 09N TO 20N W OF 132W AND FROM 11N TO 16N BETWEEN 
125W AND 132W. THE STRONG TRADES ARE ENHANCING CONVERGENCE INTO 
THE ITCZ AND MAINTAINING THE AREA OF CONVECTION BETWEEN 125W AND 
135W AS MENTIONED ABOVE. THE RIDGE WILL WEAKEN AND THE AREAL 
COVERAGE OF STRONG TRADE WINDS WILL DECREASE OVER THE NEXT 24 
HOURS WITH TRADES DIMINISHING BELOW 25 KT BY WED EVENING. 

GULF OF PAPAGAYO...NOCTURNAL PULSING OF WINDS TO 20 KT CAN BE 
EXPECTED OVER THE NEXT COUPLE OF NIGHTS...WITH THE POTENTIAL FOR 
STRONGER GAP FLOW LATER IN THE WEEK. 

$$
AL