000
AXPZ20 KNHC 230321
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC WED AUG 23 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0315 UTC.

...SPECIAL FEATURES...

HURRICANE ILEANA NEAR 16.6N 109.2W 979 MB AT 0300 UTC AUG 23 
MOVING NW OR 305 DEG AT 14 KT. ILEANA HAS RAPIDLY INTENSIFIED 
MAXIMUM SUSTAINED WINDS 75 KT GUSTS 90 KT. NUMEROUS STRONG 
WITHIN 90 NM N AND 75 NM S SEMICIRCLES. NUMEROUS MODERATE AND 
ISOLATED STRONG ELSEWHERE WITHIN 240 NM OF CENTER. THE EYE HAS 
EXPANDED TO ABOUT 30 NM. UPPER LEVEL OUTFLOW IS SYMMETRIC IN ALL 
QUADS. ILEANA IS TRACKING TO THE SE OF AN RIDGE AND IS EXPECTED 
TO INTENSIFY OVER THE NEXT COUPLE OF DAYS THEN WEAKEN THEREAFTER 
AS SHE MOVES OVER COOLER WATERS. SEE LATEST NHC 
FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP5/WTPZ25 KNHC 
FOR MORE DETAILS. 

TROPICAL DEPRESSION HECTOR NEAR 23.0N 138.1W 1009 MB AT 0300 UTC 
AUG 23 MOVING W OR 280 DEG AT 7 KT. MAXIMUM SUSTAINED WINDS 30 
KT GUSTS 40 KT. SCATTERED MODERATE CONVECTION IS ABOUT 280 NM NE 
OF CENTER NEAR 27N135W WITH THE LOW LEVEL CENTER TOTALLY 
EXPOSED. HECTOR SHOULD CONTINUE TO WEAKEN TONIGHT AND WED 
DISSIPATING IN ABOUT 36 HOURS. SEE LATEST NHC FORECAST/ADVISORY 
UNDER AWIPS/WMO HEADERS MIATCMEP4/WTPZ24 KNHC FOR MORE DETAILS. 

...TROPICAL WAVES...
A TROPICAL WAVE ALONG 81W HAS MOVED W ABOUT 17 KT THE PAST 24 
HOURS. SLIGHT CYCLONIC TURNING IS NOTED AS THE WAVE TRACKS W 
THROUGH A STABLE ENVIRONMENT WITH CONVECTION SUPPRESSED WITH 
ONLY I CLUSTER OVER PANAMA/COSTA RICAN BORDER.

A TROPICAL WAVE ALONG 97W N OF 3N HAS MOVED W 15 KT THE PAST 24 
HOURS. ONLY A SMALL CLUSTER OF CONVECTION IS ENHANCED ALONG THE 
ITCZ BUT BROAD CYCLONIC TURNING IS NOTED AS FAR N AS INTERIOR 
MEXICO.

...ITCZ...
THE ITCZ AXIS IS ALONG 9N79W 6N90W 15N105W 9N122W 8N140W. 
SCATTERED MODERATE ISOLATED STRONG WITHIN 120 NM EITHER SIDE OF 
LINE 4N89W 11N98W AND WITHIN 60 NM EITHER SIDE OF LINE 11N108W 
9N112W 11N120W 6N132W.

...DISCUSSION...

SW UPPER FLOW IS NOTED OVER THE DISCUSSION AREA N OF 26N W OF 
134W IN ASSOCIATION WITH A LARGE MOSTLY UPPER LEVEL CYCLONE 
CENTERED NEAR 33N152W. AN UPPER ANTICYCLONE IS CENTERED NEAR 
16N153W AND RIDGING E TO A SHARP CREST AT 20N135W...AND 
CONTINUING TO SHEAR HECTOR OVER ITS SW QUAD.   

A LARGE UPPER CYCLONE IS AT 17N124W AND SHIFTING W WITH TIME. 
ANOTHER CYCLONE OVER OLD MEXICO NEAR 25N107W IS ALSO SHIFTING W. 
TO THE N OF THESE CYCLONES...A LARGE ANTICYCLONE OVER SRN 
OKLAHOMA AT 33N94W HAS A RIDGE EXTENDING W TO ANOTHER 
ANTICYCLONE AT 32N118W WITH RIDGING CONTINUING SW TO ANOTHER 
ANTICYCLONE AT 26N127W. THIS RIDGE WILL PLAY A LARGE PART IN THE 
STEERING OF HURCN ILEANA. 

AN UPPER ANTICYCLONE IS AT 20N90W...WITH ITS ENVELOPE OF 
ANTICYCLONIC FLOW DOMINATING THE UPPER LEVELS N OF 10N BETWEEN 
83W AND 101W.   

$$
NELSON