000
AXPZ20 KNHC 181527
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SAT AUG 18 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1515 UTC.

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

THE MONSOON TROUGH AXIS WAS ANALYZED FROM 10N85W TO 09N92W TO 
13N105W TO 10N110W TO 15N125W TO 10N140W. SCATTERED MODERATE TO 
ISOLATED STRONG CONVECTION WAS NOTED FROM 05N TO 09N BETWEEN 93W 
AND 97W...AND WITHIN 120 NM EITHER SIDE OF TROUGH AXIS BETWEEN 
103W AND 106W. SCATTERED MODERATE CONVECTION ALSO NOTED WITHIN 
120 NM S OF AXIS BETWEEN 128W AND 133W.

...DISCUSSION...

A 1008 MB LOW PRES...THE REMNANT OF HECTOR...IS CENTERED NEAR 
23N117W. AN ALTIMETER PASS FROM AROUND 0930 UTC CROSS THE CENTER 
OF THE LOW AND SHOWED SEAS TO 7 FT WITH WINDS TO 15 KT. AN 
EARLIER 05 UTC ASCAT PASS SHOWED ONLY LIGHT TO MODERATE FLOW ON 
THE EASTERN SIDE OF THE STORM. THE MAIN ISSUE RELATED TO THE 
REMNANT LOW OF HECTOR HAS BEEN COPIOUS MOISTURE POOLING FROM 
SOUTHERN BAJA THROUGH NW MAINLAND MEXICO. A TONGUE OF MOISTURE 
CONTINUES TO PIVOT ACROSS NORTHERN BAJA THIS MORNING BUT IS 
DIMINISHING. CONVECTION HAS LARGELY ABATED ACROSS THE GULF OF 
CALIFORNIA ACCORDINGLY. 

A 1018 MB HIGH PRES AREA CENTERED NEAR 29N13W WILL BLOCK THE 
MOVEMENT OF THE REMNANT LOW OF HECTOR...WHICH WILL DRIFT 
SLOWLY NNE TOWARD NORTHERN BAJA BEFORE DISSIPATING OVER THE NEXT 
24 TO 48 HOURS. THE HIGH PRES WILL ALSO BLOCK A COLD FRONT 
APPROACHING THE AREA FROM THE N CENTRAL PACIFIC. FAIRLY WEAK 
TRADE WIND FLOW S OF THE HIGH PRES ALONG WITH LIGHT TO MODERATE 
SW FLOW S OF THE MONSOON TROUGH ARE MAINTAIN AREAS OF MODERATE 
CONVECTION ALONG THE TROUGH AXIS.

CLUSTERS OF WESTWARD DRIFTING CONVECTION CONTINUE TO 
SPORADICALLY FORM AND DISSIPATE N OF 05N AND E OF 115W. THIS 
CONVECTION IS IN PART DUE TO LOW LEVEL CONVERGENCE OF LIGHT TO 
MODERATE SW FLOW S OF THE MONSOON TROUGH. ANOTHER FACTOR IS THE 
PRESENCE OF A MID TO UPPER LEVEL TROUGH NOTED IN CIMMS SATELLITE 
DERIVED WINDS MIGRATING THROUGH 105W OVER THE PAST 12 HOURS. 

SOUTHERLY SWELL TO 8 FT WITH PERIODS TO 14 SECONDS WILL PUSH 
ACROSS THE EQUATOR AND REACH AS FAR NORTH AS 05N GENERALLY E OF 
120W BY LATE SUN.

$$
CHRISTENSEN