000
AXPZ20 KNHC 200909
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC MON AUG 20 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0745 UTC.

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

THE MONSOON TROUGH AXIS WAS ANALYZED FROM 08N77W TO 09N83W THEN 
CONTINUES FROM 13N105W TO 12N113W TO 08N118W TO LOW PRES NEAR 
13N127W TO 11N130W. THE ITCZ AXIS WAS ANALYZED FROM 11N130W TO 
10N140W. SCATTERED MODERATE CONVECTION WAS WITHIN 120 NM S OF 
THE AXIS E OF 81W. 

...DISCUSSION...

AN EXPANSIVE ANTICYCLONE ALOFT NEAR 32N115W EXTENDS RIDGE AXES 
SOUTHWESTWARD TO 25N140W AND SOUTHEASTWARD THROUGH THE GULF OF 
CALIFORNIA TO 10N100W. AN UPPER LOW S OF THE WESTERN RIDGE 
AXIS NEAR 20N134W IS PUMPING MID TO UPPER LEVEL MOSITURE INTO 
THE AREA N OF 20N BETWEEN 125W AND 138W. DIFFLUENT CONDITIONS 
ASSOCIATED WITH THE EASTERN RIDGE AXIS ALOFT ARE ENHANCING THE 
CONVECTION IN THE GULF OF CALIFORNIA AND ALONG THE CENTRAL AND 
SOUTHERN MEXICAN COAST. SCATTERED MODERATE TO STRONG CONVECTION 
LIES IN THE GULF OF CALIFORNIA FROM 24N TO 29N AND SCATTERED 
MODERATE CONVECTION WAS FOUND WITHIN 210 NM S OF THE GULF OF 
TEHUANTEPEC BETWEEN 93W AND 96W. THE 0424 UTC ASCAT PASS 
SUGGESTS A TROUGH REMAINS OFFSHORE OF CENTRAL MEXICO...BUT THE 
PASS MISSED THE TROUGH AXIS. SHIP SJCD REPORTED 16 KT NE WINDS 
NEAR 19N 105.5W AT 0600 UTC IN THE AREA WHERE WINDS WERE 
EXPECTED TO BE STRONGEST BETWEEN THE TROUGH AND THE HIGH TERRAIN 
OF CENTRAL MEXICO. THE TROUGH WAS ANALYZED ALONG 106W FROM 15N 
TO 23N. SCATTERED MODERATE CONVECTION WAS FOUND WITHIN 90 NM E 
OF THE TROUGH FROM 15N TO 20N AND WITHIN 60 NM W OF THE TROUGH 
BETWEEN 21N AND 23N. THIS TROUGH IS EXPECTED TO GRADUALLY WEAKEN 
OVER THE NEXT FEW DAYS.
 
1022 MB HIGH PRES CENTERED NEAR 30N135W IS BEING IMPINGED UPON 
BY A WEAKENING COLD FRONT JUST NW OF THE FORECAST AREA. THE 1025 
MB PARENT SUBTROPICAL HIGH IS WELL TO THE NW NEAR 37N164W. THE 
COMPROMISED SUBTROPICAL RIDGE HAS YIELDED TRADE WINDS ONLY AS 
STRONG AS A MODERATE BREEZE OVER THE FORECAST AREA. THE REMAINS 
OF HECTOR WERE ANALYZED ON THE EASTERN EDGE OF THE RIDGE NEAR 
23N116W AS A 1011 MB LOW PRES SYSTEM AT 0600 UTC. THE 0426 UTC 
ASCAT PASS SHOWS LIGHT WINDS ON THE NE SIDE OF THE CIRCULATION 
WITH WINDS ONLY AS STRONG AS A GENTLE BREEZE IN THE SW QUADRANT. 
THERE IS NO DEEP CONVECTION ASSOCIATED WITH THE SYSTEM. THE 
REMNANTS OF HECTOR ARE EXPECTED TO DISSIPATE TODAY. 

CROSS-EQUATORIAL S SWELL TO 8 FT WILL LIE OVER THE FORECAST AREA 
S OF 03N THE NEXT FEW DAYS. 

$$
SCHAUER