000 AXPZ20 KNHC 171541 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC THU AUG 17 2006 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1500 UTC. ...SPECIAL FEATURES... HECTOR HAS INTENSIFIED TO A HURRICANE AND AT 1500 UTC AUG 17 IS LOCATED NEAR 14.7N 121.2W 979 MB MOVING WNW OR 290 DEG AT 11 KT. HURRICANE FORCE WINDS EXTEND WITHIN 20 NM AND TROPICAL STORM FORCE WINDS WITHIN 100 NM OF THE CENTER. 12 FT SEAS EXTEND WITHIN 150 NM EXCEPT WITHIN 200 NM IN THE NW QUADRANT. MAXIMUM SUSTAINED WIND SPEED HAS INCREASED TO 75 KT WITH GUSTS TO 90 KT. AFTER BECOMING STEADY STATE IN INTENSITY DURING THE DAY YESTERDAY HECTOR HAS BEEN GAINING STRENGTH THIS MORNING. THE STRUCTURE OF THE STORM HAS ALSO CHANGED SIGNIFICANTLY FROM A CONDENSED CENTRAL DENSE OVERCAST WITH A POORLY DEFINED BAND YESTERDAY TO MORE OF A BANDED HURRICANE TODAY WITH A CENTRAL DENSE OVERCAST FEATURE IN THE INNER CORE REGION. GOOD OUTFLOW CHANNEL IS SEEN IN THE SOUTHERN HALF OF THE CIRCULATION. NUMEROUS MODERATE TO STRONG CONVECTION IS FROM 12N-17N BETWEEN 119W-123W. HECTOR IS FORECAST TO STRENGTHEN A LITTLE BIT MORE IN THE NEXT 24 HOURS BEFORE STEADY WEAKENING OVER COOLER WATERS AND INCREASING SHEAR. FOR MORE DETAILS SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP4/WTPZ24 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... SOUTHERN PORTION OF A TROPICAL WAVE HAS ENTERED THE EXTREME EASTERN PORTION OF THE AREA N OF 4N TO THE PANAMA COAST INTO THE CARIBBEAN SEA ALONG 81W MOVING W NEAR 15 KT. ISOLATED MODERATE TO STRONG CONVECTION IS WITHIN 150 NM OF THE WAVE AXIS. TROPICAL WAVE ALONG 109W/110W FROM 4N-17N MOVING W 15 KT. THIS WAVE IS SLIGHTLY MORE DEFINED THAN THE WAVE TO THE E WITH SOME CYCLONIC CURVATURE NOTED IN THE LOW-MID LEVEL CLOUDS ABOUT THE AXIS. ISOLATED SHOWERS AND TSTMS ARE FROM 5N-12N BETWEEN 108W-112W. TROPICAL WAVE ALONG 139W FROM 4N-18N MOVING W 15 KT. ANY SIGNATURE OF THIS WAVE IS BEING MASKED BY A LOW PRES AREA TO ITS WEST. SCATTERED MODERATE CONVECTION IS WITHIN 3 DEGREES OF AXIS. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 8N81W 8N105W 8N108W 11N115W 12N137W 11N140W. BESIDES FOR THE CONVECTION ASSOCIATED WITH THE TROPICAL WAVES...ISOLATED MODERATE CONVECTION IS WITHIN 90 NM OF THE AXIS E OF 89W. ...DISCUSSION... A BROAD MID-UPPER LEVEL RIDGE REMAINS ESTABLISHED ACROSS THE AREA WITH THE AXIS EXTENDING FROM NRN MEXICO SWWARD TO A LARGE ANTICYCLONE CENTERED NEAR 17N133W. A MID-UPPER TROUGH HAS DEVELOPED A WEAKNESS IN THIS RIDGE N OF 22N BETWEEN 122W-132W. THIS TROUGH WILL REMAIN IN THIS AREA OVER THE NEXT FEW DAYS AND WILL LIKELY HELP TO TURN HECTOR MORE NORTHWARD. MID LEVEL EASTERLIES LIE S OF 20N AND HECTOR IS EMBEDDED IN THEM. DRY STABLE UPPER LEVEL AIR COVERS THE MAJORITY OF THE AREA N OF A LINE ALONG 15N140W 18N123W 28W114W. WIDESPREAD MOISTURE LIES TO THE S OF THIS LINE...BUT BESIDES THE CONVECTION ASSOCIATED WITH THE HURRICANE ONLY A LIMITED AMOUNT OF IT IS DEEP IN NATURE. A WEAK ANTICYCLONE CENTERED OVER CENTRAL AMERICA NEAR 16N89W WITH RIDGING EXTENDING TO 100W IS SPREADING DEBRIS MID-HIGH LEVEL MOISTURE NORTHWARD TO SRN MEXICO. ON THE SURFACE...THE PACIFIC RIDGE HAS CHANGED LITTLE OVER THE PAST 48 HRS. THE RIDGE IS PRODUCING NE TRADES OF 20 KT BETWEEN 14N AND 20N W OF 130W. WINDS ALONG THE BAJA COAST ARE MOSTLY LIGHT UNDER A WEAK PRESSURE GRADIENT. GAP WINDS ARE MOSTLY LIGHT ALSO. $$ JC/LL