000
AXPZ20 KNHC 230347
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL 
0405 UTC MON SEP 23 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 
0330 UTC.

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

MONSOON TROUGH AXIS EXTENDS ACROSS CENTRAL AMERICA FROM 08N78W 
TO 09N83W TO 14N92W...THEN WESTWARD ACROSS THE PACIFIC TO 
11N100W TO 10N140W. SCATTERED MODERATE/ISOLATED STRONG 
CONVECTION IS WITHIN 150 NM S OF THE TROUGH BETWEEN 89W AND 98W.

...DISCUSSION...

E-W ORIENTED RIDGE EXTENDS ALONG 33N FROM HIGH PRES CENTERED 
NEAR 155W TO 125W. WEAK RIDGING AND LIGHT PRES GRADIENT PREVAILS 
OVER NW PORTION N OF 20N W OF 120W. CONVERGENCE ZONE SNAKES 
ALONG 10N W OF 100W WITH MINIMAL CONVECTION. TIGHT PRES GRADIENT 
N OF 30N ALLOWING NLY WINDS TO INCREASE...WITH SEAS TO 8-9 FT 
NEAR THE COAST OF NORTHERN BAJA CALIFORNIA. A WEAK PRES PATTERN 
WILL PERSIST ELSEWHERE ACROSS THE AREA. A COLD FRONT WILL WEAKEN 
AND DISSIPATE W OF N CALIFORNIA TONIGHT THROUGH MON NIGHT. NW 
SWELL FROM THIS FRONT WILL INCREASE SEAS UP TO 11 FT N OF 25N W 
OF 120W MON NIGHT THROUGH TUE NIGHT. BUILDING HIGH PRES BEHIND 
THE FRONT WILL TIGHTEN THE PRES GRADIENT ALONG THE CALIFORNIA 
COAST TUE NIGHT THROUGH THU...PRODUCING STRONG N-NW WINDS N OF 
THE AREA WITH NW SWELL BUILDING TO 10-12 FT E OF 120W NEAR BAJA.

$$
MUNDELL