000
AXPZ20 KNHC 082152
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SAT AUG 08 2009

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN
FROM THE EQUATOR TO 32N...EAST OF 140W. 

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2130 UTC.

...TROPICAL WAVES...

TROPICAL WAVE NORTH OF 07N ALONG 96W HAS MOVED W OF THE GULF OF 
TEHUANTEPEC. THE WAVE WAS MOVING W AT 12 KT OVER THE PAST 24 
HOURS. WIDELY SCATTERED MODERATE CONVECTION WITH A HINT OF 
CYCLONIC TURNING IS NOTED NEAR AND TO THE EAST OF THE WAVE AXIS. 

TROPICAL WAVE FROM 06N TO 14N ALONG 125W/126W WAS MOVING W 10 KT 
OVER THE PAST 24 HOURS. SATELLITE IMAGERY SHOWED ONLY WIDELY 
ISOLATED MODERATE CONVECTION WITHIN 90 NM EITHER SIDE OF THE 
WAVE AXIS FROM 10N TO 13N. MORE ORGANIZED SCATTERED CONVECTION 
WAS NOTED IN ASSOCIATION WITH A SURFACE LOW NEAR 13N117.5W. 

...ITCZ...

THE AXIS IS FROM 05N77W TO 08N90W TO 10N110W 13N118W TO 09130W 
TO 10N140W. SCATTERED MODERATE CONVECTION IS FROM 02N TO 05N 
BETWEEN 80W AND 85W...FROM 05N TO 07N BETWEEN 87W AND 91W...AND 
FROM 08N TO 13N BETWEEN 91W AND 93W. 
    
...DISCUSSION...

A MIDDLE AND UPPER LEVEL TROUGH EXTENDS FROM A CYCLONIC 
CIRCULATION OVER THE INTERMOUNTAIN WESTERN UNITED STATES INTO 
THE AREA ALONG 32N121W TO A CYCLONIC CIRCULATION NEAR 25N128W. 
THIS FEATURE APPEARS TO BE THE REMNANT MID LEVEL CIRCULATION OF 
FORMER T.D. ENRIQUE...NOW REFLECTED AT THE SURFACE AS A 
WEAKENING TROUGH FROM 22N TO 26N ALONG 130W. 

FURTHER W...A MID TO UPPER LEVEL ANTICYCLONE NEAR 24N138W 
CONTINUES TO PROVIDE STEERING AND GOVERNS THE UPPER LEVEL 
ENVIRONMENT AROUND DEPARTED HURRICANE FELICIA. REFER TO 
ADVISORIES ISSUED BY THE CENTRAL PACIFIC HURRICANE CENTER UNDER 
AWIPS/WMO HEADERS TCPCP2/WTPA32 PHFO...AND THE HAWAIIAN ISLANDS 
SATELLITE INTERPRETATION MESSAGE UNDER AWIPS/WMO HEADERS 
HFOSIMHI/ATHW40 PHFO. AN AREA OF STRONG SUBSIDENCE ALOFT IS 
PUSHING SWD ALONG THE E SIDE OF THE ANTICYCLONE TO 20N BETWEEN 
127W AND 135W. 

WELL DEFINED DEEP LAYER CYCLONIC CIRCULATION IS CENTERED NEAR 
21N123W. SOME SUBSIDENCE/DRY AIR ALOFT WAS NOTED WITHIN 180 NM 
OF THE CENTER WHICH WAS MERGING WITH THE SUBSIDENCE AREA NOTED 
ABOVE.

A TROUGH OVER SOUTHEAST TEXAS AND NORTHERN MEXICO EXTENDS SW 
ACROSS WESTERN MEXICO AND INTO THE EAST PACIFIC ALONG 18N103W TO 
09N110W. DIFFLUENT FLOW WAS NOTED BETWEEN THIS TROUGH AND AN 
ANTICYCLONE LOCATED OVER NW MEXICO NEAR 29N107W. THIS
COUPLED WITH FAVORABLE OROGRAPHIC LIFTING ALONG THE SIERRA MADRE 
OCCIDENTAL IS ONCE AGAIN RESULTING IN POCKETS OF CONVECTION OVER
THE AREA AND OVER OVER THE SOUTHERN TIP OF BAJA CALIFORNIA. 

ELSEWHERE AT THE SURFACE A WEAK SURFACE RIDGE IS NORTH OF 22N 
WEST OF 115W. 

$$
COBB