000
AXPZ20 KNHC 242139
TWDEP 

TROPICAL WEATHER DISCUSSION   
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SAT MAR 24 2012

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 INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 08N114W TO 
07N125W TO 05N140W. NO SIGNIFICANT CONVECTION IS NOTED.

...DISCUSSION...

A DEEP LAYERED MID TO UPPER LEVEL LOW N OF THE AREA W OF CAPE 
MENDOCINO NEAR 40N129W EXTENDS A PAIR OF TROUGHS INTO OUR AREA. 
THE EASTERN TROUGH EXTENDS FROM THE LOW TO 32N120W TO 21N140W 
WITH THE WESTERN TROUGH EXTENDING FROM THE LOW TO 32N124W TO 
24N140W. AN AREA OF MOISTURE IS PRESENT WITHIN 120 NM AHEAD OF 
THE EASTERN TROUGH AND WITHIN 90 NM AHEAD OF THE WESTERN TROUGH 
WITH DRY AIR NOTED ELSEWHERE W OF THE EASTERN TROUGH. ELSEWHERE 
IN THE MID TO UPPER LEVELS...GENERALLY ZONAL FLOW EXISTS WITH 
SCATTERED PACKETS OF MOISTURE BEING ADVECTED FROM THE W TO THE E 
ACROSS THE TROPICS.

THE TROUGHS MENTIONED ABOVE ARE SUPPORTING A DECAYING COLD FRONT 
ACROSS THE AREA FROM 30N125W TO 26N130W TO 24N137W. NW-N 20-25 
KT WINDS ARE N OF 24N W OF THE FRONT WITH SW 20 KT WINDS N OF 
29N WITHIN 240 NM E OF THE FRONT. LARGE NW SWELL TO 18 FT EXISTS 
W OF THE FRONT WITH THE HIGHEST SEAS NEAR 30N132W. THIS FRONT 
WILL DISSIPATE DURING THE NEXT 24 HOURS WITH A REINFORCING COLD 
FRONT REACHING FROM 30N124W TO 26N127W TO 24N131W BY SUN 
AFTERNOON. ALSO...A SECONDARY SET OF NW SWELL WILL BUILD SEAS TO 
UP TO 20 FT NEAR 30N126W. WINDS WILL INCREASE TO 20-30 KT IN THE 
N CENTRAL WATERS NEAR THE FRONT AS A SURFACE LOW SKIRTS BY JUST 
N OF THE AREA. THE GFS INDICATES THE POTENTIAL FOR GALE FORCE 
WINDS N OF 30N WHILE THE ECMWF PROGS A WEAKER SCENARIO. BOTH 
MODEL SOLUTIONS HAVE TRENDED WEAKER DURING THE PAST 24 HOURS. 
THE FRONT WILL DISSIPATE BY 48 HOURS WITH THE LARGE NW SWELL 
GRADUALLY DECAYING TO 8-13 FT BY MON AFTERNOON.

SOUTHERLY 20-25 KT WINDS ARE FORECAST IN THE FAR NORTHERN GULF 
OF CALIFORNIA N OF 30N LATE TONIGHT THROUGH MON MORNING AHEAD OF 
THE COLD FRONTS MENTIONED ABOVE.

SOUTHWESTERLY SWELL TO 8 FT WITH PEAK WAVE PERIODS OF 13-15 
SECONDS EXISTS S OF 11N BETWEEN 102W AND 118W. THIS SWELL IS 
FORECAST TO DECAY TO LESS THAN 8 FT WITHIN THE NEXT 24 HOURS.

A RATHER PERSISTENT SURFACE TROUGH IS OBSERVED FROM 09N84W TO 
05N90W...WITH SCATTERED MODERATE AND ISOLATED STRONG CONVECTION 
PRESENT WITHIN 120 NM S OF THE TROUGH. EXPECT THE TROUGH TO 
LINGER ACROSS THE SAME GENERAL AREA THROUGH THE NEXT 24-48 HOURS.

$$
LEWITSKY