000 AXPZ20 KNHC 260913 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC WED AUG 26 2009 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 0845 UTC. ...SPECIAL FEATURE... TROPICAL STORM IGNACIO WAS CENTERED NEAR 21.1N 122.5W OR ABOUT 710 NM W OF THE SOUTHERN TIP OF BAJA CALIFORNIA AT 26/0900 UTC...MOVING NW OR 305 DEGREES AT 12 KT. MAXIMUM SUSTAINED WINDS WERE 45 KT WITH GUSTS TO 55 KT AND THE ESTIMATED MINIMUM PRESSURE WAS 1000 MB. WHILE THE COVERAGE OF CONVECTION HAS DECREASED...IT REMAINS ORGANIZED NEAR THE CENTER AND IN A LARGE CURVED BAND N AND E OF THE CENTER. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS WITHIN 210 NM NE AND 60 NM SW SEMICIRCLES. WEAKENING IS FORECAST AS IGNACIO MOVES OVER INCREASINGLY COOLER WATERS AND IT SHOULD BECOME A REMNANT LOW IN A COUPLE OF DAYS. ADDITIONAL INFORMATION CAN BE FOUND UNDER AWIPS/WMO HEADERS MIATCMEP3/WTPZ23 KNHC. ...TROPICAL WAVES... A TROPICAL WAVE IS ALONG 88W/89W N OF 05N MOVING W NEAR 15 KT OVER THE PAST 24 HOURS. LOW TO MID-LEVEL CLOUD MOTIONS SUGGEST A SMALL CIRCULATION ALONG THE AXIS JUST SOUTH OF EL SALVADOR. CONVECTION HAS DEVELOPED TO THE W OF THIS SWIRL...BUT IT IS RACING WESTWARD DRIVEN BY STRONG UPPER LEVEL EASTERLY WINDS. MUCH OF THE CONVECTION OVER CENTRAL AMERICA HAS DISSIPATED EXCEPT FOR A SMALL AREA OF SOUTHERN BELIZE AND EASTERN GUATEMALA. FURTHER DEVELOPMENT...IF ANY...IS EXPECTED TO BE SLOW TO OCCUR. ...ITCZ... THE INTERTROPICAL CONVERGENCE ZONE IS ALONG 10N86W 08N105W 10N112W 15N123W 10N140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS FROM 04N TO 09N BETWEEN 105W AND 114W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS FROM 08N TO 14N BETWEEN 113W AND 115W. SCATTERED MODERATE CONVECTION IS FROM 13N TO 16N BETWEEN 121W AND 124W. SCATTERED MODERATE CONVECTION IS FROM 07N TO 10N BETWEEN 133W AND 137W.. ...DISCUSSION... A BROAD TROUGH OF LOW PRESSURE IS LOCATED ALONG 107W FROM 03N TO 12N. SATELLITE IMAGES SHOW A BROAD ENVELOPE OF LOW TO MID-LEVEL CYCLONIC TURNING WITH CONVECTION ORGANIZED IN A BROKEN BAND WELL W OF THE TROUGH AXIS. HOWEVER...ANOTHER BAND...WHICH HAS SLIGHTLY BETTER CURVATURE...HAS RECENTLY FORMED E OF THE TROUGH AXIS. AN ALTIMETER PASS INDICATED THAT SEAS ARE MAINLY 6-8 FT IN THE VICINITY OF THE TROUGH. MANY OF THE DYNAMICAL MODELS SHOW SOME DEVELOPMENT OF THIS SYSTEM OVER THE NEXT FEW DAYS AS IT TRACKS WEST-NORTHWESTWARD. ANOTHER SURFACE TROUGH IS LOCATED FARTHER W ALONG 132W EMBEDDED WITHIN THE ITCZ. QUIKSCAT DATA SHOWS A BROAD SWATH OF SW 20 KT WINDS E OF THE AXIS FEEDING INTO TROPICAL STORM IGNACIO. CONVECTION IS ISOLATED NEAR THE TROUGH FROM 07N TO 10N BETWEEN 132W-137W. THE REMAINDER OF THE REGION IS RELATIVELY QUIET...ESPECIALLY OVER THE SUBTROPICS WHERE ABUNDANT DRY AIR ALOFT IS SUPPORTING FAIR WEATHER. A LARGE UPPER TROUGH OVER THE NORTH PACIFIC IS EXPECTED TO DIG SOUTHEASTWARD OVER THE NEXT 12-24 HOURS DRAGGING A COLD FRONT TO THE NW CORNER TOMORROW NIGHT. WHILE WINDS SHOULD BE FAIRLY LIGHT ALONG THE FRONT AT THAT TIME...NW SWELL COMBINED WITH THE EFFECTS OF WEAKENING IGNACIO WILL CAUSE 8-12 FT CONFUSED SEAS OVER A LARGE PORTION OF THE SUBTROPICS W OF 125W. GULF OF TEHUANTEPEC...A HIGH RESOLUTION 0104 UTC QUIKSCAT PASS REVEALED 20-30 KT N TO NE WINDS OVER THE GULF OF TEHUANTEPEC. THIS STRONG FLOW IS EXPECTED TO CONTINUE FOR ANOTHER DAY OR SO...ESPECIALLY DURING THE OVERNIGHT AND MORNING HOURS WHEN DRAINAGE FLOW IS MAXIMIZED. HOWEVER...WINDS ARE FORECAST TO DIMINISH BY 48 HOURS AS THE TROPICAL WAVE MOVES W OF THE AREA...WHICH SHOULD LIMIT FUNNELING. $$ CANGIALOSI