000
AXPZ20 KNHC 201558
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SUN AUG 20 2006

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 
1545 UTC.

...SPECIAL FEATURES...

TROPICAL STORM HECTOR NEAR 19.8N 133.5W 986 MB AT 1500 UTC AUG 
20 MOVING WNW OR 300 DEG AT 9 KT. MAXIMUM SUSTAINED WINDS HAVE 
DROPPED TO 60 KT WITH GUSTS TO 75 KT. AREA OF DEEP CONVECTION 
HAS BECOME SOMEWHAT FRACTURED AND CONFINED TO WITHIN 120 NM OF 
THE EASTERN SEMICIRCLE OF THE STORM. THIS IS A RESULT OF A 
COMBINATION OF DRY AIR IMMEDIATELY TO THE WEST OF HECTOR 
BECOMING ENTRAINED INTO THE CIRCULATION AND INCREASING WESTERLY 
SHEAR. HECTOR SHOULD RAPIDLY DECREASE IN INTENSITY OVER THE NEXT 
24 HOURS AS THE SYSTEM TRACKS OVER INCREASINGLY COOLER WATERS 
AND REMAINS IN THE HOSTILE ENVIRONMENT. HECTOR COULD POSSIBLY BE 
DOWNGRADED TO A TROPICAL DEPRESSION SOMETIME ON MONDAY. SEE 
LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS 
MIATCMEP4/WTPZ24 KNHC FOR MORE DETAILS. 

TROPICAL WAVE ALONG 100W WITH LOW PRES 1008 MB NEAR 10N100W IS 
SHOWING SOME SIGNS OF ORGANIZATION WITH CLUSTERS OF STRONG 
CONVECTION ROTATING CYCLONICALLY AROUND THE AREA OF LOW PRESSURE 
WITH SOME ATTEMPT AT BANDING. THE SYSTEM IS LOCATED TO THE SOUTH 
OF A CYCLONIC CIRCULATION OVER THE BAY OF CAMPECHE AND WELL 
SOUTHEAST OF AN UPPER LEVEL ANTICYCLONE NEAR 21N108W IN AN AREA 
OF DIFFLUENT UPPER LEVEL FLOW. THE SYSTEM IS TRACKING WWD INTO 
AN INCREASINGLY FAVORABLE ENVIRONMENT FOR DEVELOPMENT WITH   
NWP MODELS SUGGESTING FURTHER INTENSIFICATION IS POSSIBLE AS 
WELL. AS SUCH THIS SYSTEM HAS THE POTENTIAL TO BECOME A TROPICAL 
CYCLONE WITHIN THE NEXT 36 HOURS.  

...TROPICAL WAVES...

A TROPICAL WAVE ALONG 122W FROM 3N TO 15N MOVING W AT 10 TO 15 
KT. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS WITHIN 180 
NM EITHER SIDE OF THE WAVE AXIS AND GENERALLY ALONG THE ITCZ. 

...ITCZ...
THE ITCZ AXIS ALONG 8N78W 14N97W 8N106W 8N123W 17N133W 12N140W.  
SCATTERED MODERATE/ISOLATED STRONG WITHIN 120 NM OF AXIS E OF 
124W.  ISOLATED MODERATE WITHIN 60 NM OF AXIS W OF 132W. 

ISOLATED MODERATE CONVECTION WITHIN 90 NM OF COAST E OF 97W.

...DISCUSSION...

W OF 100W...
ZONAL FLOW WITH FAIRLY STRONG WESTERLIES EXTENDS WELL INTO THE 
DISCUSSION AREA TO ALONG 22N W OF 120W. AREAS OF MODERATE TO 
STRONG UPPER LEVEL SUBSIDENCE/DRY AIR WERE INDICATED WITHIN THIS 
FLOW REGIME. TROPICAL STORM HECTOR IS EMBEDDED WITHIN THIS 
HOSTILE ENVIRONMENT WHICH SHOULD CONTRIBUTE TO RAPID WEAKENING 
OVER THE NEXT 24 HOURS. S OF 22N THE FLOW WAS RATHER AMPLIFIED 
WITH AN ANTICYCLONE NEAR 16N125W AND A DOWNSTREAM SHARP UPPER 
LEVEL SHEAR AXIS/TROUGH EXTENDING FROM JUST W OF BAJA CALIFORNIA 
SWD THROUGH 23N116W 16N115W 10N115W. A BROAD BUT DIFFUSE 
CYCLONIC CIRCULATION WAS NOTED NEAR 16N115W. ANOTHER ANTICYCLONE 
WAS CENTERED NEAR 21N108W. DIFFLUENT FLOW WAS NOTED OVER THE 
DEEP TROPICS IN THE VICINITY OF THE ITCZ WHERE CONVECTION WAS 
ACTIVE.  

E OF 100W...
DIFFLUENT FLOW SOUTH OF THE ANTICYCLONE NEAR 21N108W AND THE 
CYCLONIC CIRCULATION OVER THE BAY OF CAMPECHE NEAR 21N96W 
DOMINATED MOST OF THE TROPICAL PACIFIC E OF 100W. THIS AREA OF 
DIFFLUENCE WAS ENHANCING CLUSTERS OF STRONG CONVECTION AND 
PROVIDING A SOMEWHAT FAVORABLE ENVIRONMENT FOR FURTHER 
DEVELOPMENT OF A 1008 MB LOW NEAR 10N100W AND ASSOCIATED 
TROPICAL WAVE.    

$$
COBB