000
AXPZ20 KNHC 032115
TWDEP 

TROPICAL WEATHER DISCUSSION     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC MON SEP 03 2007

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 
2100 UTC.

...SPECIAL FEATURE...

TROPICAL STORM HENRIETTE CENTERED NEAR 20.1N 108.5W...OR 185 NM 
SSE OF CABO SAN LUCAS MEXICO...AT 03/2100 UTC MOVING NW 5 KT. 
MAXIMUM SUSTAINED WIND SPEED IS 60 KT WITH GUSTS TO 75 KT. 
ESTIMATED MINIMUM CENTRAL PRESSURE IS 981 MB. SEE LATEST NHC 
FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP1/WTPZ21 KNHC 
FOR MORE DETAILS. ON VISIBLE IMAGERY AT LEAST...HENRIETTE HAS 
BEEN LOOKING A LITTLE MORE ORGANIZED AS CONVECTIVE BANDS WRAP 
ENTIRELY AROUND THE CENTER. INFRARED IMAGERY PAINTS A SLIGHTLY 
DIFFERENT PICTURE...WITH THE CONVECTION TAKING ON A MORE 
AMORPHOUS STRUCTURE. THE LATEST MICROWAVE IMAGERY...A 1642Z TRMM 
PASS...SHOWS RELATIVELY WEAK CONVECTION NEAR THE CENTER WITH TWO 
PRIMARY STRONGER BANDS TO THE NNE AND SSW. SCATTERED MODERATE/ 
ISOLATED STRONG CONVECTION WITHIN 180 NM S AND 90 NM N 
SEMICIRCLES. SCATTERED MODERATE FROM 13N-18N BETWEEN 106W-112W.

...TROPICAL WAVES...

TROPICAL WAVE ALONG 87W/88W N OF 7N EXTENDING ACROSS EL SALVADOR 
AND WRN HONDURAS MOVING W 10-15 KT. THE WAVE IS POSITIONED ALONG 
A LINE OF TSTMS WHICH HAVE DEVELOPED FARTHER N ACROSS THE 
YUCATAN PENINSULA AND NRN GUATEMALA. OTHERWISE...THERE IS LITTLE 
INDICATION OF THE AXIS OVER THE PACIFIC WATERS...AND CONVECTION 
IS MINIMAL.

TROPICAL WAVE ALONG 98W N OF 6N MOVING W 10-15 KT. A 
WELL-DEFINED CYCLONIC CIRCULATION IS NOTED IN THE LOW-LEVEL 
CLOUD FIELD S OF THE GULF OF TEHUANTEPEC WITH THE CENTER OF 
SPINNING NEAR 9N98W. HOWEVER...DRY AIR/SUBSIDENCE IN THE MIDDLE 
AND UPPER LEVELS IS PREVENTING THE DEVELOPMENT OF DEEP 
CONVECTION. SCATTERED MODERATE CONVECTION IS FROM 12N-15N 
BETWEEN 95W-100W WHERE THE MOISTURE IS DEEPEST.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 9N83W 9N98W 15N109W 14N120W 10N140W. 
ISOLATED SHOWERS/TSTMS FROM 5N-11N BETWEEN 80W-89W. WIDELY 
SCATTERED SHOWERS/TSTMS FROM 5N-12N BETWEEN 98W-108W. SCATTERED 
MODERATE CONVECTION FROM 8N-14N BETWEEN 135W-140W.

...DISCUSSION...

E OF 110W...
AN ELONGATED UPPER RIDGE AXIS CONTINUES TO EXTEND FROM T.S. 
HENRIETTE NE ACROSS CENTRAL MEXICO TO THE NRN GULF OF MEXICO 
COAST...AND DEEP-LAYERED MOISTURE MAINLY W OF A LINE FROM THE 
ISTHMUS OF TEHUANTEPEC TO 2N107W. AN INVERTED UPPER TROUGH 
EXTENDS ON THE S SIDE OF THE RIDGE FROM 13N94W NE INTO THE ERN 
GULF OF MEXICO...AND IS RESPONSIBLE FOR THE DRY PATCH OF AIR S 
OF THE GULF OF TEHUANTEPEC. STRONG UPPER LEVEL EASTERLIES LIE S 
OF 10N AND THUS NO TROPICAL DEVELOPMENT IS EXPECTED IN THIS AREA 
OVER THE NEXT FEW DAYS. FARTHER N...THE UPPER LOW ALONG THE 
TEXAS/MEXICO BORDER HAS BEEN SHEARED INTO A SHARP TROUGH 
EXTENDING FROM THE TEXAS PANHANDLE TO NEAR LOS MOCHIS 
MEXICO...AND DRY AIR/SUBSIDENCE EXTENDS OVER THE STATES OF 
SONORA AND NRN CHIHUAHUA. THIS HAS KEPT AN OVERCAST/BROKEN DECK 
OF CLOUDS ACROSS NRN AND CENTRAL MEXICO SE OF A LINE FROM THE 
TEXAS BIG BEND TO CABO SAN LUCAS.

W OF 110W...
EXCEPT FOR T.S. HENRIETTE...LITTLE ELSE IS OCCURRING OVER THE 
REST OF THE TROPICAL PACIFIC WATERS. THE REMNANT CIRCULATION OF 
GIL...A 1012 MB LOW...IS LOCATED NEAR 20N124W BUT HAS BEEN 
STRETCHED IN AN E/W FASHION DUE TO A SURGE OF NORTHERLY FLOW AND 
SHOULD DEGENERATE INTO A SURFACE TROUGH OVER THE NEXT 24 HRS. 
THE FLOW FROM THE N IS QUITE DRY AND VISIBLE IMAGERY SHOWS 
VIRTUALLY CLEAR SKIES N OF 23N E OF 131W. A SURFACE RIDGE LIES 
OVER THE EXTREME NW PART OF THE AREA BUT IS EXPECTED TO BE 
REPLACED BY A WEAKENING COLD FRONT BY LATER TONIGHT. FARTHER 
S...LOW-LEVEL CONVERGENCE HAS INCREASED ALONG THE ITCZ DUE TO 
ENHANCED SOUTHERLIES COMING FROM THE EQUATOR...AND A CLUSTER OF 
CONVECTION HAS FORMED W OF 135W NEAR THE AXIS.
 
$$
BERG