000
AXPZ20 KNHC 240322
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC THU AUG 24 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 
0300 UTC.

...SPECIAL FEATURES...

HURRICANE ILEANA IS CENTERED NEAR 19.4N 113.5W...OR 290 NM SW OF 
THE SOUTHERN TIP OF BAJA CALIFORNIA...AT 24/0300 UTC MOVING WNW 
10 KT. MAXIMUM SUSTAINED WIND SPEED IS 105 KT WITH GUSTS TO 125 
KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 955 MB. SEE LATEST NHC 
FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP5/WTPZ25 KNHC 
FOR MORE DETAILS. ILEANA HAS CHANGED LITTLE IN STRUCTURE OVER 
THE PAST FEW HOURS. THE EYE HAS ENLARGED TO ABOUT 30 NM IN 
DIAMETER AND SOME OF THE CLOUD TOPS IN THE WRN EYEWALL HAVE 
WARMED A BIT. THERE ARE STILL TWO MAIN OUTFLOW JETS TO THE NE 
AND SW OF THE SYSTEM...AND ARE GENERALLY COINCIDENT WITH TWO 
SPIRAL BANDS CURING AROUND THE SE QUADRANT AND N SEMICIRCLE. 
NUMEROUS STRONG CONVECTION IS WITHIN 75 NM OF THE CENTER. 
SCATTERED MODERATE/STRONG IN SPIRAL BANDS ELSEWHERE WITHIN 180 
NM OF THE CENTER.

...TROPICAL WAVES...

TROPICAL WAVE ALONG 86W N OF 3N MOVING W 10-15 KT. THE MID-LEVEL 
ROTATION NOTED EARLIER HAS PERSISTED AMONG A CLUSTER OF 
CONVECTION CENTERED JUST S OF THE PANAMA/COSTA RICA BORDER. 
THERE IS NO CLEAR INDICATION OF THE EXACT POSITION OF THE 
WAVE...SO IT IS EXTRAPOLATED WWD JUST A LITTLE SLOWER TO TAKE 
THE CONVECTIVE CLUSTER INTO ACCOUNT. SCATTERED MODERATE 
CONVECTION N OF 4N BETWEEN 82W-86W.

TROPICAL WAVE SSW OF THE GULF OF TEHUANTEPEC ALONG 98W S OF 14N 
MOVING W 10-15 KT. THE CIRCULATION ASSOCIATED WITH THE WAVE 
CONTINUES TO IMPROVE...AND IS BEING HELPED BY THE FACT THAT THE 
ITCZ TURNS SHARPLY NWWD TOWARDS HURRICANE ILEANA. CONVECTION 
REMAINS DISORGANIZED BUT HAS INCREASED IN COVERAGE...WITH 
SCATTERED MODERATE FROM 6N-14N BETWEEN 94W-104W.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 7N77W 8N95W 16N105W THEN 13N113W 
8N130W 7N140W. WIDELY SCATTERED SHOWERS/TSTMS WITHIN 120 NM OF 
THE AXIS BETWEEN 113W-126W. OTHER CONVECTION ASSOCIATED WITH 
TROPICAL WAVES.

...DISCUSSION...

W OF 110W...
EXCEPT FOR HURRICANE ILEANA...THERE IS RELATIVELY LITTLE ACTIVE 
WEATHER ACROSS MUCH OF THE PACIFIC W OF 110W. THE MID/UPPER 
LEVELS ARE DOMINATED BY A SHARP TROUGH AXIS EXTENDING FROM 
8N132W TO 27N125W AND DRIFTING SLOWLY W...AND SURROUNDED BY A 
LARGE AREA OF MODERATE/STRONG SUBSIDENCE. THIS ENVIRONMENT IS 
PRODUCING A LARGE STRATOCUMULUS FIELD N OF 15N W OF 119W. THE 
REMNANT LOW/TROUGH OF HECTOR IS NOW W OF THE AREA NEAR 23N143W 
BUT IS STILL PRODUCING WINDS 20-25 KT OVER THE EXTREME NW PART 
OF THE REGION IN THE GRADIENT ADJACENT TO THE SUBTROPICAL RIDGE. 
THE DRY AIR IN THE MID/UPPER LEVELS HAS PLUNGED SWD TO THE 
EQUATOR W OF 128W ON THE BACK SIDE OF THE UPPER TROUGH AND HAS 
ESSENTIALLY EXTINGUISHED CONVECTION ALONG THE ITCZ IN THAT AREA. 
A CLUSTER OF SHOWERS/TSTMS IS NEAR THE AXIS BETWEEN 117W-126W 
CLOSER TO THE DEEPER MOISTURE. SEE SPECIAL FEATURES FOR 
DISCUSSION ON ILEANA.

E OF 110W...
AN UPPER LEVEL HIGH CENTERED NEAR MANZANILLO MEXICO WITH A RIDGE 
EXTENDING E INTO THE NW CARIBBEAN IS PRODUCING STRONG NE/E UPPER 
LEVEL FLOW OVER THE PACIFIC S OF CENTRAL AMERICA AND MEXICO. 
MAXIMUM WINDS ARE ABOUT 45-50 KT WITH 20-40 KT OF NELY 
SHEAR...SO THE CHANCES FOR EITHER OF THE TWO TROPICAL WAVES IN 
THE AREA TO DEVELOP ARE LOW AT THIS POINT.

$$
BERG