000
AXPZ20 KNHC 040335
TWDEP 

TROPICAL WEATHER DISCUSSION     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC TUE SEP 04 2007

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 
0315 UTC.

...SPECIAL FEATURE...

TROPICAL STORM HENRIETTE CENTERED NEAR 20.6N 108.8W...OR 150 NM 
SSE OF CABO SAN LUCAS MEXICO...AT 04/0300 UTC MOVING NW 6 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. THE LAST FEW VISIBLE IMAGES CONTINUED TO SHOW 
HENRIETTE OBTAINING AN IMPRESSIVE SWIRL PATTERN...YET THE 
INFRARED PATTERN CONTINUES TO LOOK ASYMMETRICAL DUE TO A LACK OF 
DEEP CONVECTION ON THE N SIDE. A 2311Z AMSU PASS INDICATED THAT 
A RING OF DEEP CONVECTION ENCIRCLES THE CENTER EXCEPT FOR A 
NARROW BREAK ON THE N SIDE. HENRIETTE IS STILL EXPECTED TO 
STRENGTHEN TO A HURRICANE AND PASS VERY NEAR CABO SAN LUCAS 
MEXICO WITHIN THE NEXT 24 HOURS...THEN WEAKEN TO A TROPICAL 
STORM AS IT RECURVES NNE OVER THE GULF OF CALIFORNIA AND INTO NW 
MEXICO. SCATTERED MODERATE/STRONG CONVECTION WITHIN 180 NM S 
SEMICIRCLE...240 NM NE AND 90 NM NW QUADRANTS. SCATTERED 
MODERATE FROM 14N-18N BETWEEN 106W-113W.

...TROPICAL WAVES...

TROPICAL WAVE ALONG 90W N OF 7N EXTENDING ACROSS GUATEMALA 
MOVING W 15 KT. THE WAVE IS POSITIONED THOUGH A LARGE CLUSTER OF 
TSTMS WHICH DEVELOPED FROM WRN HONDURAS AND EL SALVADOR NW TO 
THE YUCATAN PENINSULA...BUT THE AXIS IS BEING OVERSHADOWED BY 
THE CIRCULATIONS OF HURRICANE FELIX OVER THE WRN CARIBBEAN AND 
THE TROPICAL WAVE ALONG 99W. SCATTERED MODERATE/STRONG 
CONVECTION N OF 12N BETWEEN 88W-94W.

TROPICAL WAVE ALONG 99W N OF 6N MOVING W 10-15 KT. A 
WELL-DEFINED BUT BROAD CYCLONIC CIRCULATION IS NOTED IN THE 
LOW-LEVEL CLOUD FIELD SW 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 TSTMS ALONG THE MEXICAN COAST NEAR 
AND 150 NM E OF ACAPULCO MEXICO.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 9N83W 9N98W 15N109W 14N120W 10N140W. 
SCATTERED MODERATE CONVECTION FROM 6N-11N E OF 88W. SCATTERED 
SHOWERS/TSTMS 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 IS MAINLY W OF A LINE FROM THE 
ISTHMUS OF TEHUANTEPEC TO 4N108W. AN INVERTED UPPER TROUGH 
EXTENDS ON THE S SIDE OF THE RIDGE FROM 13N96W 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. HOWEVER...HURRICANE FELIX IS OVER THE SW 
CARIBBEAN AND IS EXPECTED TO MAKE LANDFALL OVER NE NICARAGUA OR 
ERN HONDURAS EARLY TUE MORNING...THEN MOVE WNW TOWARDS GUATEMALA 
AND SE MEXICO THROUGH WED AND THU. WINDS COULD INCREASE OUT OF 
THE W TO AT LEAST 20 KT OFF THE PACIFIC COASTS OF NICARAGUA...EL 
SALVADOR...AND GUATEMALA AS FELIX TRACKS BY TO THE N. CONVECTIVE 
ACTIVITY COULD ALSO BECOME MORE WIDESPREAD IN THIS AREA. 

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 LA PAZ MEXICO.

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 IS BEING 
STRETCHED 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 22N E OF 132W. 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 SHOWERS/TSTMS HAS FORMED W OF 
135W NEAR THE AXIS.
 
$$
BERG