000 AXPZ20 KNHC 040901 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC WED OCT 04 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0845 UTC. ...TROPICAL WAVES... TROPICAL WAVE ALONG 91W N OF 4N TO INLAND GUATEMALA IS MOVING W ABOUT 10 KT. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 30 NM OF 13N91W. WIDELY SCATTERED MODERATE CONVECTION IS NOTED ACROSS THE ITCZ FROM 4N-9N BETWEEN 90W-92W. NO TROPICAL DEVELOPMENT IS EXPECTED FROM THIS WAVE OVER THE NEXT FEW DAYS AS IT REMAINS RATHER ON THE WEAK SIDE. TROPICAL WAVE ALONG 111W FROM 3N TO 15N IS MOVING W 10-15 KT. SURFACE CONVERGENCE E OF THE WAVE AXIS CONTINUES TO RESULT IN WIDELY SCATTERED MODERATE CONVECTION MAINLY IN THE VICINITY OF THE ITCZ AS DESCRIBED BELOW...AND ALSO FROM 11N-15N BETWEEN 111W-118W WHICH IS ALSO AIDED BY A SMALL UPPER LEVEL CYCLONIC CIRCULATION MOVING W 17 KT TO THE WEST OF THE WAVE NEAR 16N115W. NONE OF THE CONVECTIVE AREAS ASSOCIATED WITH THIS WAVE INDICATE ANY SIGNS OF ORGANIZATION. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 8N79W 7N90W 9N100W 10N110W 9N120W 9N130W 9N140W. SCATTERED MODERATE TO STRONG CONVECTION IS ALONG AND WITHIN 180 NM S OF THE ITCZ W OF 130W. SCATTERED MODERATE/ ISOLATED STRONG CONVECTION IS ALONG AND WITHIN 60 NM S OF THE ITCZ BETWEEN 123W-130W...AND ALSO WITHIN 60 NM EITHER SIDE OF THE ITCZ BETWEEN 84W-87W...97W-101W AND 106W-123W. SCATTERED TO NUMEROUS STRONG CONVECTION IS WITHIN 75 NM OF 15N93W. ...DISCUSSION... W OF 110W... BROAD LONGWAVE TROUGH NORTH OF 12N CONTINUES TO BE THE DOMINANT FEATURE ACROSS THIS AREA. AN EMBEDDED SHORTWAVE TROUGH EXTENDS INTO THE REGION THROUGH 32N128W...AND EXTENDS SOUTHWESTWARD THROUGH 28N134W TO 26N140W. A 3 DEG WIDE JET STREAM BRANCH ROUNDS THE SOUTH SIDE OF THE TROUGH STRETCHING FROM 23N140W NORTHEASTWARD THROUGH 26N130W TO ACROSS SOUTHERN CALIFORNIA. UPPER AIR DATA INDICATES MAXIMUM WINDS OF NEAR 65 KT NEAR THE JET STREAM CORE FROM 119W-126W. UPPER LEVEL CONVERGENCE FOUND BEHIND THE TROUGH IS USHERING MODERATE SUBSIDENCE IN THE WAKE OF THE TROUGH. A DISSIPATING SURFACE TROUGH ASSOCIATED WITH THE UPPER LEVEL TROUGH EXTENDS THROUGH PART OF THE NW PORTION FROM A WEAK 1016 MB LOW NORTH OF THE AREA NEAR 33N131W SOUTHWEST TO 27N137W. A 1018 MB LOW DROPPING SOUTHWESTWARD 15-20 KT IS ANALYZED WEST OF THE TROUGH NEAR 27N137W. ISOLATED SHOWERS AREA POSSIBLE WITHIN 60 NM OF THE TROUGH. A QUIKSCAT PASS FROM FROM LATE LAST NIGHT SHOWED N-NE WINDS OF 20 KT TO THE NORTHWEST OF THE TROUGH JUST ALONG AND NORTH OF 32N. THIS SURGE IS FORECAST TO WEAKEN BEFORE MOVING SOUTH INTO THE REGION. A 1019 MB HIGH IS ANALYZED NEAR 27N127W WITH A RIDGE EXTENDING SOUTHEASTWARD TO 24N115W. GENERALLY WEAK HIGH PRESSURE COVERS THE AREA NORTH OF 20N...BUT IS FORECAST TO STRENGTHEN TOWARDS THE END OF THE WEEK. DIFFLUENT FLOW PATTERN EAST OF THE TROUGH IS ENHANCING ITCZ CONVECTION BETWEEN 119W-122W. IN ADDITION STRONG UPPER LEVEL ANTICYCLONIC FLOW ALOFT S OF THE UPPER TROUGH IS SUSTAINING A VERY ACTIVE PORTION OF THE ITCZ WEST OF 132W. A STRONG UPPER HIGH IS CENTERED SOUTHWEST OF THE SOUTHERN TIP OF BAJA CALIFORNIA NEAR 23N111W WITH ASSOCIATED MODERATE SUBSIDENCE AREA NOTED FROM 15N-27N BETWEEN 110W-119W. E OF 110W... MODERATE SUBSIDENCE...AN EXTENSION OF THE SUBSIDENCE MENTIONED ABOVE...AND ASSOCIATED DRY AIR IS BEING ADVECTED SOUTHWARD ON THE WESTERN SIDE OF A SHARP UPPER TROUGH MOVING EASTWARD OVER THE EASTERN PART OF MAINLAND MEXICO. WATER VAPOR IMAGERY SUGGESTS THAT A RATHER FLATTENED UPPER LEVEL ANTICYCLONE IS CENTERED NEAR 11N106W WITH A RIDGE EXTENDING SOUTHEASTWARD TO NEAR 6N93W. BROAD N-NE UPPER FLOW PATTERN DOMINATES THE AREA EAST OF THE ANTICYCLONE. LARGE CONVECTIVE ERUPTING TO THE SOUTHEAST OF THE TROUGH IS OVER THE EASTERN GULF OF TEHUANTEPEC DROPPING SOUTH-SOUTHWEST UNDERNEATH BROAD SCALE ANTICYCLONIC FLOW FOUND TO THE EAST OF THE TROUGH. UPPER LEVEL DIFFLUENCE EAST OF THE TROUGH IS PRODUCING SCATTERED MODERATE/ISOLATED STRONG CONVECTION OVER SOUTHEAST MEXICO INCLUDING ITS SOUTHEAST COAST. THIS CONVECTIVE ACTIVITY...AND IN ADDITION ANY DEEP CONVECTION THAT DEVELOPS ALONG AND NEAR THE CENTRAL AMERICAN COAST AS WELL IS STEERED TO THE WEST AND SOUTHWEST BY THE UPPER N-NE FLOW DOMINATING THIS AREA. AT THE SURFACE...GAP WINDS OF 20-30 KT CONTINUE ACROSS THE GULF OF TEHUANTEPEC AS SEEN IN A QUIKSCAT PASS FROM LAST NIGHT AND IN SURFACE OBSERVATIONS INLAND MEXICO NEAR THE GULF OF TEHUANTEPEC...WHILE LIGHTER NE GAP FLOW OF 20 KT IS NOTED OVER THE GULF OF PAPAGAYO. FLOW HERE SHOULD DIMINISH IN ABOUT 18-24 HRS...AND DECREASE TO 20 KT OVER THE GULF OF TEHUANTEPEC IN ABOUT 48 HRS. MODERATE TO STRONG SUBSIDENCE AND DRY STABLE AIR IS SEEN SOUTH OF 6N BETWEEN 95W-110W AND S OF 2N E OF 95W. $$ AGUIRRE