000 AXPZ20 KNHC 091005 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC TUE OCT 09 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0945 UTC. ...SPECIAL FEATURE... TROPICAL DEPRESSION OLIVIA WAS DOWNGRADED TO A POST-TROPICAL REMNANT LOW NEAR 15.2N 122.0W 1008 MB AT 09/0900 UTC MOVING SW AT 06 KT. MAXIMUM SUSTAINED WIND SPEED IS 30 KT WITH GUSTS TO 40 KT. THE LOW LEVEL CENTER IS EXPOSED AS SEEN ON IR IMAGERY. THE ONLY REMAINING CONVECTION IS NOTED AS ONE TSTM CELL WELL REMOVED FROM THE CENTER NEAR 17N118W. THE REMNANT LOW IS FORECAST TO CONTINUE IN A SW DIRECTION THROUGH THE NEXT FEW HOURS ...THEN TRACK IN A W TO SW DIRECTION INTO THE NEXT 12-24 HRS... AND WEAKENED INTO A TROUGH IN OR NEAR 48 HRS ALONG A POSITION FROM 17N126W TO 11N129W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS W ACROSS NORTHERN COSTA RICA TO THE PACIFIC COAST AT 10N85W TO 11N96W TO 09N103W TO 06N117W WHERE IT LOSES IDENTITY IN SOUTHERLY FLOW TO THE S AND SW OF POST TROPICAL CYCLONE OLIVIA. THE MONSOON TROUGH RESUMES SW OF THE LOW AT 13N122W AND CONTINUES SW TO 07N135W WHERE LOW LEVEL WINDS INDICATE IT TRANSITIONS TO THE ITCZ WHICH IN TURN CONTINUES W TO BEYOND 06N140W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 120 NM S OF THE TROUGH BETWEEN 90W-93W...BETWEEN 95W-97W ...AND BETWEEN 100W-103W. SCATTERED MODERATE CONVECTION IS WITHIN 120 NM S OF THE TROUGH BETWEEN 107W-110W. ...DISCUSSION... A BROAD UPPER TROUGH ADVANCING EASTWARD IS N OF 24N AND E OF 135W. AN SHORTWAVE TROUGH IS ROTATING THROUGH THIS TROUGH... AND EXTENDS FROM 32N129W SW TO A LOW W OF THE AREA AT 19N144W. A COLD FRONT ASSOCIATED WITH THE TROUGH IS APPROXIMATELY WITHIN 530 NM NW OF THE AREA. THIS FRONT IS FORECAST TO BE JUST TO THE NW OF THE AREA BY THU. AN UPPER LEVEL ANTICYCLONE IS LOCATED E OF THE POST TROPICAL CYCLONE OLIVIA AT 15N117W WITH AN UPPER RIDGE EXTENDING NNE TO THE SOUTHERN PORTION OF THE SW U.S. AN UPPER RIDGE EXTENDS ENE FROM THE ANTICYCLONE TO ANOTHER ANTICYCLONE NEAR 18N111W. A RIDGE ALSO EXTENDS WSW TO A CREST AT 12N139W. UPPER DEBRIS MOSITURE FROM POST TROPICAL CYCLONE OLIVIA AND ITS REMAINING CONVECTION IS SEEN STREAMING NE TOWARDS SOUTHERN BAJA CALIFORNIA AS IT GETS CAUGHT UP IN A NE TO SW JET STREAM BRANCH THAT EXISTS BETWEEN THE BROAD UPPER TROUGH AND THE UPPER THAT EXTENDS NNE FROM THE ANTICYCLONE AT 15N117W. CLOUD MOTION VECTORS INDICATE WINDS OF 50-70 KT WITH THE JET STREAM BRANCH. AN UPPER SHORTWAVE TROUGH IS MOVING THROUGH EASTERN N AMERICA TRAILING A TROUGH SW ACROSS THE GULF OF MEXICO AND OVER CENTRAL MEXICO THROUGH AN UPPER CYCLONE OVER THE PACIFIC AT 16N103W... WITH THE UPPER TROUGH CONTINUING S TO BASE OVER THE TROPICAL PACIFIC AT 11N103W. THE UPPER DIFFLUENCE E OF THE TROUGH AXIS...AND OVER THE E SEMICIRCLE OF THE UPPER CYCLONE...EARLIER ENHANCED CONVECTION OVER CENTRAL MEXICO. THIS CONVECTION HAS DIMINISHED DURING THE OVERNIGHT HRS. THE DEBRIS MOISTURE IS BRING ADVECTED NE ACROSS THE GULF OF MEXICO. THE SOUTHERN EXTENT OF THIS UPPER TROUGH CONTINUES TO SEPARATE THE UPPER FLOW OVER THE TROPICAL PORTION OF THE DISCUSSION AREA. AN UPPER ANTICYCLONE OVER THE WESTERN CARIBBEAN AT 13N81W HAS ITS ANTICYCLONIC ENVELOPE EXTENDING S OVER THE DISCUSSION AREA TO THE N OF 07N AND E OF 101W. THE ASSOCIATED UPPER DIFFLUENCE IS SUPPORTING THE CONVECTION ALONG THE EASTERN SEGMENT OF THE MONSOON TROUGH AS PREVIOUSLY DESCRIBED. DENSE DEBRIS MOISTURE IS OBSERVED WITHIN THIS UPPER RIDGE TURNING N ALONG THE RIDGE PERIPHERY AT 101W...THEN NE OVER MEXICO E OF 98W WHERE IT MERGES INTO A DENSE TROPICAL PLUME THAT CONTINUES NE ACROSS THE EASTERN GULF OF MEXICO AND MOST OF E FLORIDA AHEAD OF THE PARENT DEEP LAYERED TROUGH. ELSEWHERE AT THE LOW LEVELS...SURFACE HIGH PRESSURE OF 1020 MB TO 1022 MB CONTINUES TO MEANDER NEAR 27N127W WITH BROAD RIDGING COVERING THE DISCUSSION AREA N OF 21N W OF THE BAJA PENINSULA. GAP WINDS...NORTHERLY WINDS WILL PULSE AT 20-25 KT THROUGH AND DOWNSTREAM THE GULF OF TEHUANTEPEC REACHING NEAR 14N96W INTO EALY THIS EVENING....THEN GUIDANCE SUGGESTS WINDS WILL DIMINISH THROUGH TONIGHT BY WED NIGHT WINDS INCREASE AGAIN TO 20-25 KT IN THE GULF. BY THEN...EXPECT A COUPLE OF SURFACE LOWS TO HAVE DEVELOPED FURTHER S ALONG 10N-11N WITHIN THE MONSOON TROUGH...WITH THE NORTHERLY DRAINAGE FLOW THROUGH TEHUANTEPEC ENHANCING THE FLOW OVER THE N SEMICIRCLE OF THE LOWS. CONTINUING TO TONE DOWN THE GFS GUIDANCE WHEN POPULATING THE GRIDS E OF 105W. $$ AGUIRRE