000
AXPZ20 KNHC 100328
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC TUE AUG 10 2010

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

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0230 UTC.

...SPECIAL FEATURE...

AT 10/0300 UTC...THE CENTER OF TROPICAL DEPRESSION ESTELLE IS 
LOCATED NEAR 17.6N 113.0W MOVING TOWARD THE WEST OR 265 DEGREES 
AT 4 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1005 MB. MAXIMUM 
SUSTAINED WINDS ARE 30 KT WITH GUSTS TO 40 KT. ESTELLE HAS 
SCATTERED MODERATE CONVECTION IN THE NORTHWEST QUADRANT WITHIN 
150 NM OF THE CENTER. STRONG SOUTHEASTERLY VERTICAL SHEAR 
REMAINS. FURTHER WEAKENING IS EXPECTED WITH ESTELLE BECOMING A 
POST TROPICAL REMNANT LOW BY 24 HOURS. SEE THE LATEST NHC 
FORECAST/ ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP2/WTPZ22 KNHC 
FOR MORE DETAILS.

...ITCZ...

THE ITCZ AXIS IS ALONG 13N87W TO 14N92W TO 15N100W TO 12N118W TO 
12N122W TO 11N137W. SCATTERED MODERATE AND ISOLATED STRONG 
CONVECTION IS WITHIN 150 NM S OF THE AXIS E OF 91W. NUMEROUS 
MODERATE AND ISOLATED STRONG CONVECTION IS WITHIN 240 NM S OF 
THE AXIS BETWEEN 100W AND 110W. SCATTERED MODERATE CONVECTION IS 
WITHIN 90 NM N OF THE AXIS BETWEEN 104W AND 110W.
 
...DISCUSSION...

AN UPPER LEVEL ANTICYCLONE IS LOCATED NEAR 16N140W. VERY DRY AIR 
UNDER MODERATE TO STRONG SUBSIDENCE IS PRESENT ACROSS THE AREA N 
OF THE ITCZ AND W OF 121W AS SHOWN IN BOTH THE WATER VAPOR AND 
TOTAL PRECIPITABLE WATER SATELLITE IMAGERY. A FLATTENING UPPER 
LEVEL TROUGH ENTERS THE FORECAST AREA NEAR 32N116W AND CONTINUES 
SW TO NEAR 24N124W. THIS AREA OF TROUGHINESS SEPARATES THE UPPER 
ANTICYCLONE NOTED ABOVE FROM ANOTHER UPPER LEVEL ANTICYCLONE 
LOCATED OVER N CENTRAL MEXICO NEAR 23N101W WITH A RIDGE AXIS 
EXTENDING W INTO THE E PACIFIC TO NEAR 21N121W. TROPICAL 
DEPRESSION ESTELLE IS EMBEDDED IN THE FAIRLY STRONG UPPER LEVEL 
SOUTHEASTERLY FLOW TO THE SW OF THIS ANTICYCLONE WHICH HAS 
TAKEN A TOLL ON THE TROPICAL CYCLONE.

EASTERLY/ZONAL FLOW EXISTS ACROSS THE MAJORITY OF THE REMAINDER 
OF THE DISCUSSION AREA S OF 17N AND E OF 120W.

AT THE SURFACE...A RIDGE DOMINATES THE NORTHERN WATERS 
ORIGINATING FROM 1032 MB HIGH PRES CENTERED WELL NW OF THE AREA 
NEAR 36N147W ENTERING THE DISCUSSION AREA NEAR 28N140W AND 
CONTINUING THROUGH 20N120W. A WEAK SURFACE TROUGH EXTENDING FROM 
32N127W TO 31N133W TO 32N139W HAS NUDGED THE RIDGE MORE TO THE S 
ALTHOUGH THE TROUGH IS EXPECTED TO DISSIPATE AS IT MOVES S OF 
30N ON TUE. DIURNALLY ENHANCED NW WINDS TO 20 KT WILL OCCUR 
WITHIN 120 NM OF THE W COAST OF BAJA CALIFORNIA FROM 24N TO 
28N... MAINLY DURING THE EVENING HOURS...THROUGH THE NEXT 48 
HOURS.

A MONSOON TROUGH HAS BECOME A LITTLE LESS DEFINED COMPARED TO 24 
HOURS AGO ALTHOUGH IT IS STILL RESPONSIBLE FOR NUMEROUS AREAS OF 
DEEP CONVECTION BETWEEN 100W AND 110W...AND ALSO BETWEEN 91W AND 
96W. SW WINDS OF 20 TO 25 KT CONTINUE S OF THE ITCZ TO 09N 
BETWEEN 100W AND 124W WITH COMBINED SEAS OF 8 TO 12 FT. THESE SW 
WINDS ARE BLEEDING SW SWELL OF 8 TO 10 FT N OF THE ITCZ TO 17N 
BETWEEN 100W AND 115W. THIS OVERALL WEATHER PATTERN WILL PERSIST 
DURING THE NEXT FEW DAYS. 

CROSS EQUATORIAL SW SWELLS DOMINATING THE MAJORITY OF THE 
SOUTHERN AND EASTERN PORTIONS OF THE FORECAST WATERS WILL 
GRADUALLY DECAY THROUGH WED. A NEW SOUTHWESTERLY SWELL TRAIN 
WITH PERIODS OF 14 TO 16 SECONDS IS EXPECTED TO CROSS THE 
EQUATOR BETWEEN 105W AND 125W TONIGHT...THEN WILL SPREAD OVER
MOST OF THE BASIN S OF 13N TO 15N BY WED.

$$
LEWITSKY