000
AXPZ20 KNHC 082109
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL 
2205 UTC SUN DEC 08 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2100 UTC.

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

THE MONSOON TROUGH EXTENDS FROM 09N85W TO 07N97W WHERE LOW LEVEL 
WINDS SUGGEST A TRANSITION TO ITCZ WHICH EXTENDS TO 08N121W TO 
BEYOND 06N140W. SCATTERED MODERATE CONVECTION WAS NOTED FROM 04N 
TO 07N BETWEEN 80W AND 86W. SCATTERED MODERATE CONVECTION WAS 
NOTED WITHIN 90 NM N OF ITCZ BETWEEN 97W AND 100W. SCATTERED 
MODERATE CONVECTION WAS NOTED WITHIN 60 NM S OF ITCZ BETWEEN 
133W AND 137W. SCATTERED MODERATE CONVECTION WAS NOTED WITHIN 90 
NM N OF ITCZ W OF 137W. 

...DISCUSSION... 

HIGH PRESSURE OF 1028 MB IS CENTERED NEAR 28N130W WITH A RIDGE 
EXTENDING SE TO NEAR 17N108W. THE PRESSURE GRADIENT BETWEEN THE 
AREA OF HIGH PRESSURE AND LOWER PRESSURE IN THE VICINITY OF THE 
ITCZ IS SUPPORTING A LARGE AREA OF FRESH TO STRONG TRADES FROM 
10N TO 22N W OF 120W AND FROM 10N TO 15N BETWEEN 115W AND 120W 
WITH SEAS TO 11 FT. THE HIGH PRES WILL DISSIPATE BY MON AS A 
WEAK COLD FRONT MOVES ACROSS THE N WATERS. THE FRONT WILL USHER 
IN A NEW SET OF NW SWELLS BEFORE THE FRONT DISSIPATES BY TUE. 
HIGH PRESSURE IN THE WAKE OF THE FRONT WILL MAINTAIN THE TIGHT 
PRESSURE GRADIENT OVER THE FORECAST AREA TO CONTINUE TO SUPPORT 
A LARGE AREA OF FRESH TO STRONG TRADES N OF THE ITCZ THROUGH 
TUE.  

GULF OF TEHUANTEPEC...THE AIR MASS N OF AREA IN THE GULF OF 
MEXICO HAS MODIFIED AND WINDS FUNNELING INTO THE GULF OF 
TEHUANTEPEC HAVE DIMINISHED BELOW GALE FORCE. WINDS WILL FURTHER 
DIMINISH BELOW 25 KT BY TONIGHT WITH SEAS SUBSIDING BELOW 8 FT. 
RELATIVELY BENIGN CONDITIONS WILL REMAIN IN PLACE OVER THE GULF 
OF TEHUANTEPEC FROM LATE TONIGHT INTO TUE...WITH ONLY LIGHT TO 
MODERATE GAP BREEZES AT THEIR HIGHEST DURING MAINLY THE 
OVERNIGHT AND EARLY MORNING HOURS. LOOKING AHEAD...A STRONGER 
COLD FRONT WILL PUSH THROUGH THE WESTERN GULF OF MEXICO LATE 
TUE. THE COMBINATION OF THE DENSER AIR FUNNELING THROUGH THE GAP 
WITH STRONG HIGH PRES BUILDING BEHIND THE FRONT OVER NE MEXICO 
WILL DELIVER ANOTHER ROUND OF GALE FORCE WINDS TO THE GULF OF 
TEHUANTEPEC STARTING LATE TUE NIGHT OR EARLY WED MORNING AND 
CONTINUING THROUGH FRI. WINDS MAY REACH NEAR STORM FORCE BY LATE 
THU WITH SEAS BUILDING TO AROUND 15 FT. 

GULF OF CALIFORNIA...HIGH PRES WILL BUILD OVER THE GREAT BASIN 
OF THE WESTERN UNITED STATES. THIS WILL SET UP A STRONG GRADIENT 
FOLLOWED BY 20 TO 25 KT WINDS FUNNELING INTO THE NORTHERN GULF 
OF CALIFORNIA BY MONDAY AFTERNOON AND REACHING NEAR GALE FORCE 
BY MON EVENING. THE NW WINDS WILL PUSH DOWN THE LENGTH OF THE 
GULF THROUGH LATE MONDAY AND TUESDAY...WITH SEAS REACHING 8-9 FT.

GULF OF PAPAGAYO...WINDS WILL PULSE TO 25 KT DURING THE 
OVERNIGHT AND EARLY MORNING HOURS OF MONDAY BEFORE DIMINISHING 
BELOW 25 KT BY MON AFTERNOON. 

$$
AL