000 AXPZ20 KNHC 171508 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC SUN SEP 17 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1430 UTC. ...SPECIAL FEATURES... TROPICAL STORM MIRIAM IS CENTERED NEAR 19.2N 113.9W...OR 310 NM SW OF THE SOUTHERN TIP OF BAJA CALIFORNIA...AT 17/1500 UTC MOVING NNE 3 KT. MAXIMUM SUSTAINED WIND SPEED IS 40 KT WITH GUSTS TO 50 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1002 MB. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP4/WTPZ24 KNHC FOR MORE DETAILS. MIRIAM IS EMBEDDED IN NE MID/UPPER LEVEL FLOW ON THE SE SIDE OF A LARGE HIGH...AND THE RESULTANT NELY SHEAR IS KEEPING THE LOW-LEVEL CENTER SOMEWHAT EXPOSED. A CLOSED MID/UPPER LOW NEAR 31N133W IS EXPECTED TO DROP SE DURING THE NEXT COUPLE OF DAYS...AND EVENTUALLY STEER MIRIAM TO THE N OFF THE BAJA PENINSULA. NUMEROUS MODERATE/STRONG CONVECTION IS WITHIN 180 NM SW QUADRANT. TROPICAL DEPRESSION LANE IS CENTERED INLAND NEAR 26.3N 107.6W... OR 90 NM ENE OF LOS MOCHIS MEXICO...AT 17/1500 UTC MOVING NNW 6 KT. MAXIMUM SUSTAINED WIND SPEED IS 25 KT WITH GUSTS TO 35 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1005 MB. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP3/WTPZ23 KNHC FOR MORE DETAILS. THE LOW-LEVEL CENTER OF LANE IS TRAPPED ALONG THE W SLOPES OF THE SIERRA MADRE OCCIDENTALS AND HAS COMPLETELY DECOUPLED FROM THE MID-LEVEL CIRCULATION...WHICH IS NOW OVER THE MEXICAN PLATEAU. ALL DEEP CONVECTION HAS DISSIPATED...LEAVING ONLY SCATTERED SHOWERS IN THE MOUNTAINS. THIS IS THE LAST ADVISORY ISSUED BY THE NATIONAL HURRICANE CENTER ON LANE. ...TROPICAL WAVES... TROPICAL WAVE EXTENDING ACROSS NICARAGUA AND COSTA RICA ALONG 84W N OF 4N MOVING W 15 KT. SLIGHT TURNING IN LOW/MID-LEVEL CLOUDS FROM NICARAGUA EXTENDING NWD INTO THE GULF OF HONDURAS PROVIDE PLACEMENT OF THE WAVE AXIS. ONLY ISOLATED SHOWERS/TSTMS ARE LOCATED NEAR THE WAVE...AND THE BULK OF THE MORE SCATTERED CONVECTION LIES N AND S OF PANAMA. TROPICAL WAVE ALONG 94W N OF 4N MOVING W 15-20 KT. A TROPICAL SQUALL LINE IS PROPAGATING WWD FROM THE GULF OF TEHUANTEPEC SWD. VAGUE LOW-LEVEL CYCLONIC TURNING IS NOTED IN THIS AREA. SCATTERED MODERATE CONVECTION IS FROM 10N-16N BETWEEN 91W-96W. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 7N77W 8N85W 6N106W 13N117W 10N130W 10N140W. SCATTERED MODERATE CONVECTION N OF 3N BETWEEN 77W-83W. SCATTERED MODERATE WITHIN 150 NM OF THE AXIS BETWEEN 98W-115W. WIDELY SCATTERED SHOWERS/TSTMS WITHIN 120 NM OF THE AXIS BETWEEN 123W-134W. ...DISCUSSION... A LARGE MID/UPPER LEVEL LOW IS LOCATED OVER THE NW PART OF THE DISCUSSION AREA NEAR 31N133W WITH ITS ASSOCIATED TROUGH EXTENDING SW TO 28N140W. THE LARGE UPPER HIGH WHICH HAS BEEN LOCATED W OF THE BAJA PENINSULA HAS BEEN SUPPRESSED FARTHER S TODAY BY THE MID/UPPER LOW...WITH ITS AXIS NOW STRETCHING FROM CENTRAL BAJA SW TO 16N140W. DRY AIR ASSOCIATED WITH THIS UPPER HIGH IS BEING PULLED EWD OVER NW MEXICO BY AN AMPLIFIED UPPER TROUGH OVER THE WRN UNITED STATES...AND IS ALSO RESPONSIBLE FOR LIFTING THE REMNANTS OF LANE ONTO THE MEXICAN PLATEAU AND SW TEXAS. ELSEWHERE...THE LOW-LEVEL MOISTURE CONVEYOR BELT STILL RESIDES ALONG AND JUST S OF THE ITCZ AXIS...STRETCHING FROM 10N140W IN THE DEEP TROPICS MAKING ITS WAY NEWD TO THE MOUTH OF THE GULF OF CALIFORNIA IN THE WAKE OF LANE. T.S. MIRIAM IS CLINGING ONTO THE N SIDE OF THE MOISTURE BELT AND SO IS PARTIALLY SUCCUMBING TO DRIER AIR AND VERTICAL SHEAR. LINGERING MOISTURE OFF THE COAST OF MEXICO BETWEEN MANZANILLO AND MAZATLAN COULD STILL BE FORCED INLAND TODAY AND PRODUCE ADDITIONAL RAINS...ESPECIALLY OVER THE W FACING SLOPES OF THE SIERRA MADRE OCCIDENTALS. OVER THE FAR E PACIFIC...LOW-LEVEL NLY FLOW EXTENDS FROM MAINLAND MEXICO TOWARDS THE ITCZ AS THE PATTERN BUCKLES FROM THE MONSOON TROUGH NEAR BAJA...AND TRIES TO RECONNECT TO THE MAIN ITCZ AXIS ALONG 7N E OF 110W. THIS FLOW IS BRINGING DRIER AIR FROM THE N OVER THE AREA...AND IS LIMITING CONVECTION BETWEEN 90W-110W. SHOWERS/TSTMS HAVE BEEN LOCATED NEAR A PAIR OF TROPICAL WAVES...ONE WHICH IS PRODUCING A TROPICAL SQUALL LINE OFF THE COAST OF GUATEMALA AND TEHUANTEPEC...AND THE OTHER WHICH IS LEAVING A LARGE CLUSTER OF TSTMS IN ITS WAKE OFF THE W COAST OF COLOMBIA NWD ACROSS PANAMA. $$ BERG