000
AXPZ20 KNHC 010302
TWDEP 

TROPICAL WEATHER DISCUSSION                                    
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
0405 UTC THU JAN 01 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 
0300 UTC. 
 
...SPECIAL FEATURES...                                        
HIGH PRES BUILDING ACROSS SOUTHERN MEXICO HAS TIGHTENED THE 
PRESSURE GRADIENT AND INCREASED GAP WINDS THROUGH THE CHIVELA 
PASS INTO THE GULF OF TEHUANTEPEC TO NEAR GALE FORCE. THE 
PRESSURE GRADIENT WILL FURTHER TIGHTEN OVERNIGHT...ENABLING 
WINDS TO INCREASE TO MINIMAL GALE FORCE...N-NE 30 TO 35 KT WITH 
SEAS 10 TO 12 FT. THE GALE WILL BE SHORT LIVED AND WINDS WILL 
DECREASE BELOW GALE FORCE BY THU AFTERNOON...THEN FURTHER 
DECREASE TO 20 KT LESS BY EARLY FRI.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...              
THE MONSOON TROUGH EXTENDS FROM 06N77W TO 05N90W WHERE LOW LEVEL 
WINDS SUGGEST A TRANSITION TO ITCZ WHICH EXTENDS TO 07N110W TO 
04N117W TO BEYOND 06N140W. NO SIGNIFICANT CONVECTION WAS NOTED.

...DISCUSSION... 

A WEAK COLD FRONT EXTENDS ACROSS BAJA CALIFORNIA NORTE TO 
27N120W. FRESH NORTHERLY FLOW IS CROSSING 30N BEHIND THE 
FRONT...ACCOMPANIED BY SHORT PERIOD SWELL OF 8 TO 9 FT. THE COLD 
FRONT WILL DISSIPATE TONIGHT...WHILE THE SWELL IS EXPECTED 
SUBSIDE BELOW 8 FT BY EARLY THU. 

A WEAK SURFACE RIDGE EXTENDS FROM 30N127W TO 22N114W WHILE LOW 
PRESSURE IS CENTERED W OF THE AREA NEAR 29N155W. THE PRESSURE 
GRADIENT BETWEEN THE RIDGE AND LOW PRESSURE IS SUPPORTING FRESH 
TO STRONG WINDS OVER THE NW WATERS WITH SEAS IN THE 8 TO 10 FT 
RANGE. A SMALL AREA OF FRESH TO OCCASIONALLY STRONG WINDS WITH 
SEAS GREATER THAN 8 FT WILL CONTINUE OVER THE FAR NW WATERS 
THROUGH FRI EVENING. 

THE RELATIVELY WEAK SUBTROPICAL RIDGE IS MAINTAINING ONLY 
MODERATE TO OCCASIONALLY FRESH TRADES N OF THE ITCZ W OF 120W. 
LITTLE CHANGE IS EXPECTED.

STRONG HIGH PRESSURE CONTINUES TO PREVAIL N OF THE AREA OVER THE 
UNITED STATES. IN RESPONSE...WINDS OVER THE GULF OF PAPAGAYO 
WILL PULSE TO STRONG TO NEAR GALE FORCE DURING THE LATE NIGHT 
AND EARLY MORNING HOURS.

$$
AL