000 AXPZ20 KNHC 170341 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC SUN OCT 17 2010 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 0300 UTC. ...ITCZ... AXIS EXTENDS W FROM 09N84W TO 08N104W TO 10N121W TO 09N133W TO 12N140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION FROM 08N TO 11N BETWEEN 127W AND 131W. SCATTERED MODERATE CONVECTION WITHIN 60 NM S OF AXIS BETWEEN 88W AND 96W. ...DISCUSSION... ALOFT... A LARGE UPPER LEVEL ANTICYCLONE CENTERED NEAR 12N127W COVERS MOST OF THE DISCUSSION AREA W OF 115W. AN UPPER LEVEL TROUGH EXTENDS S FROM 32N109W TO 15N110W. WATER VAPOR IMAGERY AND SAT WINDS SHOW BROADLY DIVERGENT FLOW N OF THE ANTICYCLONE AND E OF THE UPPER LEVEL TROUGH. DIVERGENT WINDS ALOFT ARE ENHANCING DEBRIS OUTFLOW ALONG THE ITCZ BETWEEN 103W AND 110W...CONVECTIVE ACTIVITY NEAR A TROUGH ALONG 128W...AND ACTIVE CONVECTION N OF THE ITCZ IN THE CENTRAL PACIFIC NEAR 17N138W. SURFACE... A MONSOON TROUGH IS EVIDENT E OF 99W IN THE ERN PORTION OF THE DISCUSSION AREA. A WEAK 1012 MB LOW OVER PANAMA NEAR 09N81W IS PROVIDING A FOCUS FOR THE WLY MONSOON FLOW S OF COSTA RICA AND PANAMA...WITH FRESH WINDS ESTIMATED AT 15-20 KT. WV IMAGERY SHOWS ABUNDANT MOISTURE AVAILABLE E OF 97W ALONG THE ITCZ...SO PERIODS OF HEAVY RAIN AND GUSTY WINDS ARE POSSIBLE IN AND AROUND THE GULF OF PANAMA NEXT 24-48 HOURS. FURTHER W...A WEAK TROUGH ALONG 128W HAS WINDS TO 20 KT NEAR TROUGH AXIS AND SEAS TO 8 FT. OTHERWISE A BROAD HIGH PRES RIDGE DOMINATES NW PORTION OF AREA. GAP WINDS... BASED ON OBSERVED DATA AND MODEL GUIDANCE...WINDS ARE EXPECTED TO BE BELOW GALE FORCE IN THE GULF OF TEHUANTEPEC AND DOWNSTREAM. WEAKENING HIGH PRES IN THE GULF OF MEXICO AND WINDS SHIFTING TO ENE OVER THE NEXT 24 HOURS MEANS WINDS WILL BE BELOW 20 KT THERE WITHIN 18-24 HOURS. GRADIENT WINDS AT PAPAGAYO ARE MARGINAL AND EXPECTED TO DIMINISH BELOW 20 KT WITHIN A FEW HOURS. $$ MUNDELL