000 AXPZ20 KNHC 041015 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC WED SEP 05 2007 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1000 UTC. ...SPECIAL FEATURE... TROPICAL STORM HENRIETTE WAS UPGRADED TO HURRICANE STATUS AT 0900 UTC...AND CENTERED NEAR 21.4N 109.1W OR ABOUT 120 NM SOUTH-SOUTHEAST OF THE SOUTHERN TIP OF BAJA CALIFORNIA MOVING NNW AT 7 KT. MAXIMUM SUSTAINED WIND SPEED IS 65 KT WITH GUSTS TO 80 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 978 MB. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP1/WTPZ21 KNHC FOR MORE DETAILS. OVER THE PAST SEVERAL HOURS HENRIETTE AS CONTINUED TO ACQUIRE BANDING FEATURES WITH DEEPENING CONVECTION PARTICULARLY OVER THE E SEMICIRCLE WHERE SCATTERED STRONG CONVECTION IS EVIDENT WITHIN 60-90 NM OF THE CENTER. THE OVERALL STRUCTURE OF THE SYSTEM HAS BECOME MORE SYMMETRICAL AS WELL DURING THE PAST FEW HOURS. HENRIETTE IS FORECAST TO STRENGTHEN SLIGHTLY OVER THE NEXT 6-12 HOURS AS IT MAKES LANDFALL OVER SOUTHERN BAJA...THEN MAKES LANDFALL OVER NW MEXICO IN ABOUT 36-48 HOURS. HENRIETTE IS THEN EXPECTED TO WEAKEN TO A TROPICAL STORM INLAND NORTHERN MEXICO NEAR 28.4N 110.4W IN 48 HOURS. ...TROPICAL WAVES... TROPICAL WAVE ALONG 91W/92W N OF 7N EXTENDS N ACROSS GUATEMALA ...AND IS MOVING W 12 KT. SCATTERED STRONG CONVECTION IN CLUSTERS ARE ALONG AND WITHIN 100 NM S OF THE COAST OF GUATEMALA AND SE MEXICO. TROPICAL WAVE ALONG 100W N OF 6N IS 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 10N99W. HOWEVER...DRY AIR/SUBSIDENCE IN THE MIDDLE AND UPPER LEVELS IS PREVENTING THE DEVELOPMENT OF DEEP CONVECTION. SCATTERED STRONG CONVECTION IS NOTED OVER THE GULF OF TEHUANTEPEC AND THE FAR SE PART OF MEXICO SPREADING WESTWARD TOWARDS 98W. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 8N84W 8N91W 8.5N100W 8N110W 11.5N120W 13N130W 10N140W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 30 NM EITHER SIDE OF THE AXIS BETWEEN 92W-94W. ...DISCUSSION... E OF 110W... AN ELONGATED UPPER RIDGE AXIS CONTINUES TO EXTEND FROM HURRICANE 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 ARE NOTED IN THE UPPER AIR DATA TO BE S OF 13N. HURRICANE FELIX IS OVER THE SW CARIBBEAN AND IS EXPECTED TO MAKE LANDFALL OVER NE NICARAGUA IN JUST A FEW HOURS. FELIX IS THEN FORECAST TO WNW ACROSS NICARAGUA TODAY AND HONDURAS LATER TODAY AND TONIGHT. THE REMNANTS ARE EXPECTED TO PASS ACROSS GUATEMALA AND SE WED AND THU. HEAVY RAINFALL COULD BECOME 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. A WEAK SURFACE MOVING SSE 10-15 KT IS ALONG 22N122W 19N125W. THE FLOW FROM THE N IS QUITE DRY. A SURFACE RIDGE IS 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. $$ AGUIRRE