000
AXPZ20 KNHC 160343
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC WED DEC 16 2015

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
0330 UTC.               
 
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...            

A WEAK TROUGH EXTENDS FROM 10N86W TO 08N100W TO 07N115W. AXIS OF
THE ITCZ EXTENDS FROM 07N115W TO 10N127W TO BEYOND 03N140W.
SCATTERED MODERATE ISOLATED STRONG CONVECTION WAS NOTED WITHIN
120-180 NM N OF THE AXIS BETWEEN 120W AND 127W. SCATTERED
MODERATE CONVECTION WAS NOTED FROM 05N TO 08N BETWEEN 100W AND
103W.
 
...DISCUSSION...

EXPANSIVE 1035 MB HIGH PRESSURE CENTERED NORTH OF THE AREA NEAR
36N137W IS SLOWLY DRIFTING TO SE. RIDGE AXIS EXTENDS FROM THE
HIGH SOUTHEASTWARD THROUGH 30N130W TO 22N115W. THE PRESSURE
GRADIENT BETWEEN THE HIGH AND LOWER PRESSURES ALONG THE ITCZ
MAINTAINS A BROAD ZONE OF 20-25 KT TRADE WINDS IN AN AREA FROM
08N TO 25N W OF 130W AND FROM 11N TO 23N BETWEEN 122W AND
130W...WITH SEAS GENERALLY 10 TO 12 FT IN NE SWELL. ANOTHER AREA
OF 20 KT KT WINDS IS N OF 23N BETWEEN 118W AND 125W...WITH SEAS
FROM 12 TO 14 FT IN NW SWELL. THIS AREA OF FRESH TO STRONG WINDS
WILL DIMINISH OVERNIGHT. THE LARGE AREA OF FRESH TO STRONG
TRADES WILL PERSIST THROUGH LATE WED THEN SHRINK ON THU AS THE
HIGH PRESSURE N OF THE AREA WEAKENS AND DRIFTS SOUTHWARD TO
ALONG 31N.  

THE PRESSURE GRADIENT BETWEEN HIGH PRESSURE OVER THE GREAT BASIN
AND A DEVELOPING SURFACE TROUGH ALONG THE COAST OF MEXICO IS
FORECAST TO TIGHTEN IN THE VICINITY OF THE GULF OF CALIFORNIA
WITHIN 24 HOURS ALLOWING NW TO N WINDS TO INCREASE TO 20 TO 25
KT...POSSIBLY REACHING 30 KT AT TIMES ON THU. THE FETCH OF WINDS
DOWN THE ENTIRE LENGTH OF THE GULF WILL SUPPORT SEAS OF 8 TO 9
FT NEAR THE ENTRANCE OF THE GULF BY LATE THU. 
 
A WEAKENING EXTRATROPICAL CYCLONE OVER THE BERING SEA IS NOW
GENERATING A ROUND OF LONG PERIOD...20 TO 22 SECOND...NW SWELL
CURRENTLY MOVING INTO THE FAR NW PORTION OF THE FORECAST AREA.
THESE SWELLS WILL MOVE SE AND EXTEND FROM CENTRAL BAJA
CALIFORNIA TO 18N130W LATE WED AND FROM CABO CORRIENTES TO
05N125W BY LATE THU. COASTAL MARINE INTERESTS ALONG BAJA
CALIFORNIA AND NEARBY ISLANDS SHOULD REMAIN ALERT FOR THESE
HAZARDOUS MARINE CONDITIONS AND ONGOING DANGEROUS SURF
CONDITIONS.   

LOOKING AHEAD...ONE OF THE STRONGEST COLD FRONTS OF THE SEASON
THUS FAR IS FORECAST TO PUSH THROUGH THE GULF OF MEXICO LATE THU
AND FRI WITH AN ASSOCIATED INCREASE IN NORTHERLY WINDS TO
GALE...MOST LIKELY STORM FORCE IN THE GULF OF TEHUANTEPEC BY
LATE FRI AND FRI NIGHT.  
 
$$
COBB