000 AXPZ20 KNHC 132203 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC THU AUG 13 2009 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 2130 UTC. ...SPECIAL FEATURES... AT 2100 UTC...TROPICAL STORM GUILLERMO WAS NEAR 17.2 123.1W...OR ABOUT 860 NM W-SW OF THE SOUTHERN TIP OF BAJA CALIFORNIA... MOVING TOWARD THE WEST OR 280 DEGREES AT 13 KT. MAXIMUM SUSTAINED WINDS WERE ESTIMATED AT 60 KT WITH GUSTS TO 75 KT. ESTIMATED MINIMUM CENTRAL PRESSURE WAS 992 MB. SEE THE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP5/WTPZ25 KNHC FOR MORE DETAILS. GOOD ANTICYCLONIC OUTFLOW CONTINUES OVER GUILLERMO...WITH EVACUATION HAVING IMPROVED ACROSS THE SE QUADRANT IN THE PAST FEW HOURS. DEEP CONVECTION ASSOCIATED WITH GUILLERMO CONTINUES CONCENTRATED ACROSS THE S SEMICIRCLE...AND WAS MORE ISOLATED ACROSS THE N HALF. A CLOUD FREE FEATURE NEAR THE CENTER HAS BEEN INTERMITTENT TODAY...WITH IMPROVED BANDING SEEMING TO WRAP INTO THE E SIDE OF GUILLERMO INDICATING THE SYSTEM IS APPROACHING HURRICANE STRENGTH. THIS INTENSIFICATION IS FORECAST DURING THE NEXT 12 TO 24 HOURS...AS IT CONTINUES TO MOVE WEST-NORTHWESTWARD. THE REMNANTS OF TROPICAL DEPRESSION NINE-E HAVE FLARED UP TODAY CONVECTIVELY UNDER THE SW PERIPHERY OF THE RIDGE VENTING GUILLERMO. THIS SYSTEM REMAINS IN A MOIST ENVIRONMENT AND WILL CONTINUE TO MOVE WESTWARD THROUGH AN AREA OF WEAK UPPER LEVEL SHEAR. THERE IS A MEDIUM CHANCE...30 TO 50 PERCENT...OF THIS SYSTEM BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. ...TROPICAL WAVES... AFTER MUCH INTERROGATION OF LONG TERM SATELLITE IMAGERY...TPW ANIMATIONS...SUNY ALBANY GFS DIAGNOSTICS AND VARIOUS OTHER DATA...RELOCATION OF TROPICAL WAVES HAS BEEN IMPLEMENTED FOR THE 18Z MAP. A TROPICAL WAVE WAS ESTIMATED BETWEEN 80W AND 83W...WITH A POSITIVE SE TO NW TILT...FROM THE FAR EASTERN PACIFIC TO NICARAGUA...MOVING W NEAR 15 KT. ELONGATED UPPER LEVEL ANTICYCLONIC FLOW ALONG 10N BETWEEN 60W AND 90W WAS VENTING SCATTERED DEEP CONVECTION IN ASSOCIATION WITH THE S AMERICA MONSOONAL CIRCULATION E OF 83W...AND ACROSS NICARAGUA. A TROPICAL WAVE WAS ESTIMATED BETWEEN 99W AND 101W...WITH A POSITIVE SE TO NW TILT...MOVING W 15 TO 20 KT. WIDESPREAD MODERATE TO STRONG CONVECTION WAS OCCURRING WITH AND AHEAD OF THIS WAVE AS THE BEST MOISTURE AND CONVERGENCE HAS BEEN OCCURRING AHEAD OF IT...AND WAS BEING ENHANCED BY SYNOPTIC SCALE LIFT AND UPPER DIVERGENCE ASSOCIATED WITH A TUTT LOW OFF THE W COAST OF CENTRAL MEXICO. THIS TUTT LOW HAS MOVED FROM JUST N OF THE NE CARIBBEAN W-SW AND ACROSS CENTRAL AMERICA THE PAST SEVERAL DAYS...AND HAS REMAINED JUST OUT AHEAD...OR W OF THIS WAVE. ...ITCZ... THE INTERTROPICAL CONVERGENCE ZONE WAS ANALYZED ALONG THE LINE...09N84W TO 09N108W TO 16N121W TO 11N140W. SCATTERED MODERATE CONVECTION WITHIN 30 NM OF AXIS BETWEEN 95W AND 98W...AND WITHIN 150 NM EITHER SIDE OF AXIS BETWEEN 100W AND 110W. ...DISCUSSION... AN UPPER LEVEL LOW IS CENTERED OVER THE MEXICAN COAST NW OF ACAPULCO NEAR 19N103W WITH AN ASSOCIATED TROUGH COVERING THE AREA FROM 95W TO 112W NORTH OF THE ITCZ AND EXTENDING OVER CENTRAL MEXICO. DIVERGENT FLOW ALOFT ON THE SE SIDE OF THE TROUGH AND LOW HAS BEEN ENHANCING CONVECTION WITHIN AND NORTH OF THE ITCZ FROM 06N TO 16N BETWEEN 98W AND 106W. TPW ANIMATIONS SHOW A LARGE AND BROAD AREA OF ABUNDANT MOISTURE CONVERGING ACROSS THIS ZONE WITH AND IN ADVANCE OF A TROPICAL WAVE...AS THE LOW LEVEL ELY FLOW ENCOUNTERS THE CIRCULATION OF THE UPPER TROUGH. A NARROW TUTT LIKE MID TO UPPER TROUGH SNAKES ALONG A LINE FROM 34N117W TO 30N120W TO 22N129W TO THE ITCZ NEAR 133W. DRY SINKING AIR WITHIN AND TO THE NW OF THIS TROUGH WAS NOTED IN WATER VAPOR IMAGERY DUE TO DEEP LAYERED CONVERGENCE. THIS LEFT BROKEN STRATOCUMULUS IN THE LOWER LEVELS NORTH OF 17N BETWEEN 140W AND 127W AND BROKEN TO OVERCAST STRATOCUMULUS ELSEWHERE N OF GUILLERMO. BETWEEN THE TWO TROUGHS BROAD ANTICYCLONIC FLOW IS NOTED. THIS INCLUDES THE DIFFLUENT ANTICYCLONIC FLOW OVER GUILLERMO. THIS AREA IS MOIST ALOFT WITH BROKEN TO OVERCAST HIGH CLOUDS ASSOCIATED WITH GUILLERMO SOUTH OF 25N AND WEST OF 117W. WEAK SURFACE RIDGE IS NORTH OF 22N WEST OF 1205W. ELSEWHERE... THE REMNANTS OF TROPICAL DEPRESSION NINE-E HAVE FLARED UP CONVECTIVELY TODAY AND IS DISCUSSED ABOVE. DIRECTLY TO THE WEST OF THIS FORMER DEPRESSION CONTINUED A STRING OF LOW LEVEL CYCLONIC CENTERS...ALONG 13N146W AND 12N154W...MOVING W TO W-SW EMBEDDED IN THE LOW LEVEL TRADE WIND FLOW. GAP WINDS... NORTHERLY WINDS OF 20 TO 30 KT WERE DEPICTED IN MORNING SCATTEROMETER PASSES IN THE GULF OF TEHUANTEPEC REGION...WITH THE WEAKENING PLUME SUGGESTED BY SATELLITE IMAGERY TO EXTEND S-SW TO NEAR 12N. THIS GAP FLOW MAY CONTINUE FOR THE NEXT FEW DAYS...BUT WILL LIKELY DIMINISH TO LESS THAN 20 KT AFTER 18 TO 24 HOURS. NE TO E WINDS OF 20 TO 25 KT THROUGH AND DOWNSTREAM OF THE GULF OF PAPAGAYO REGION OUT TO 90W WILL CONTINUE TO PULSE UP AND DOWN THROUGH THE NEXT COUPLE OF DAYS...WITH THE POTENTIAL FOR WINDS UP TO 30 KT OVERNIGHT DUE TO NOCTURNAL DRAINAGE FLOW AND A LLVL WIND SURGE ACCOMPANYING THE TROPICAL WAVE CURRENTLY ACROSS NICARAGUA. $$ STRIPLING