000 AXPZ20 KNHC 171536 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC MON SEP 17 2012 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 1400 UTC. ...SPECIAL FEATURES... HURRICANE LANE IS CENTERED AT 16.7N 126.5W AT 1500 UTC MOVING N-NW OR 330 DEG AT 9 KT. MAXIMUM SUSTAINED WINDS ARE 65 KT WITH GUSTS TO 80 KT AND A MINIMUM PRESSURE OF 993 MB. SCATTERED STRONG CONVECTION WAS FROM 16N TO 17N BETWEEN 126W AND 127W WHILE SCATTERED MODERATE CONVECTION WAS IN BANDS ELSEWHERE FROM 12N TO 15N BETWEEN 124W AND 128W. DEEP CONVECTION HAS DECREASED SOMEWHAT OVER THE PAST FEW HOURS...BUT IT IS ASSUMED THAT OVER THE NEXT 12 HOURS OR SO LANE WILL BE OVER WATERS SUFFICIENTLY WARM TO ALLOW A LITTLE MORE STRENGTHENING. HOWEVER...IN 24 HOURS THE SEA SURFACE TEMPERATURES BENEATH THE SYSTEM SHOULD COOL TO LESS THAN 24 DEG C...SO STEADY WEAKENING SHOULD HAVE BEGUN BY THAT TIME. SEE THE LATEST NHC FORECAST/ ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP2/WTPZ22 KNHC FOR ADDITIONAL DETAILS. POST-TROPICAL CYCLONE KRISTY IS CENTERED AT 26.2N 119.5W AT 1500 UTC MOVING N-NW OR 340 DEG AT 5 KT. MAXIMUM SUSTAINED WINDS ARE 30 KT WITH GUSTS TO 40 KT AND MINIMUM PRESSURE OF 1009 MB. KRISTY HAS WEAKENED TO A REMNANT LOW AND THERE IS NO SIGNIFICANT DEEP CONVECTION NEAR ITS CENTER. THE REMNANTS OF KRISTY ARE FORECAST TO TURN NORTHEASTWARD AND DISSIPATE OVER THE NEXT 36 HOURS. SEE THE LAST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP1/WTPZ21 KNHC FOR MORE DETAILS. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH WAS ANALYZED FROM 10N85W TO 12N90W TO 07N105W TO 11N116W...RESUMING FROM 14N128W THROUGH LOW PRES 12N132W TO 09N140W. SCATTERED TO NUMEROUS STRONG CONVECTION WAS FROM 04N TO 10N BETWEEN 78W AND 81W...AND FROM 09N TO 12N BETWEEN 88W AND 90W. SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION WAS FROM 07N TO 09N BETWEEN 93W AND 96W...FROM 11N TO 15N BETWEEN 90W AND 100W...AND FROM 07N TO 08N BETWEEN 100W AND 102W. ISOLATED MODERATE CONVECTION WAS FROM 09N TO 11N BETWEEN 132W AND 134W NEAR THE LOW PRES SYSTEM EMBEDDED IN THE MONSOON TROUGH. ...DISCUSSION... THE PATTERN ALOFT FEATURES A TROUGH AXIS THAT EXTENDS SOUTHWARD FROM AN UPPER LOW N OF THE AREA NEAR 36N135W THROUGH 32N132W TO 20N140W AND A RIDGE AXIS FROM 23N130W TO 10N138W. CONVERGENCE BETWEEN THIS TROUGH AND RIDGE AXIS IS PROVIDING A SOUTHERLY STREAM OF MID TO UPPER LEVEL MOISTURE EVIDENT IN WATER VAPOR IMAGERY. FARTHER E...AN ANTICYCLONE LIES ALONG THE W COAST OF BAJA CALIFORNIA NEAR 29N116W AND EXTENDS A RIDGE AXIS SOUTHWARD THROUGH 20N115W TO JUST S OF HURRICANE LANE NEAR 10N127W. UPPER DIFFLUENCE ASSOCIATED WITH THIS RIDGE AXIS IS ENHANCING CONVECTION NEAR A WEAK SURFACE TROUGH ANALYZED ALONG 116W FROM 12N TO 17N. SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION WAS NOTED FROM 12N TO 17N BETWEEN 115W AND 119W NEAR THIS TROUGH. A DEEP LAYER TROUGH AXIS EXTENDS FROM TEXAS ACROSS NORTHERN MEXICO FROM NEAR BROWNSVILLE...TEXAS TO PUERTO VALLARTA...MEXICO. A DRY MID TO UPPER LEVEL AIR MASS AND IMPLIED SUBSIDENCE LIES BEHIND THIS TROUGH. LOW LEVEL MOSITURE IS POOLED AHEAD OF THIS TROUGH ALONG THE W COAST OF MEXICO S OF CABO CORRIENTES...WITH MUCH OF THE CONVECTIVE ACTIVITY FOUND E OF 100W. BROAD UPPER LEVEL DIFFLUENCE CAN BE FOUND OVER MUCH OF THIS AREA BETWEEN AN ANTICYCLONE OVER CENTRAL AMERICA NEAR 15N87W AND A VAST UPPER CYCLONE OFF THE COAST OF PERU NEAR 13S84W. THIS CONVECTION IS DESCRIBED IN THE SECTION ABOVE. A WEAK SURFACE LOW WAS EMBEDDED IN THE MONSOON TROUGH NEAR 12N132W. ACCORDING TO THE 0624 UTC ASCAT PASS...WINDS TO 25 KT CAN STILL BE FOUND WITHIN 90 NM E SEMICIRCLE OF THE LOW. THESE WINDS ARE EXPECTED TO DISSIPATE TODAY. $$ SCHAUER