000 AXPZ20 KNHC 190317 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC MON OCT 19 2009 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 0315 UTC. ...SPECIAL FEATURE... EXTREMELY DANGEROUS HURRICANE RICK CENTERED NEAR 17.0N 110.3W AT 19/0300 UTC...OR ABOUT 410 NM S OF THE TIP OF BAJA CALIFORNIA ...MOVING NW AT 11 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 932 MB. MAXIMUM SUSTAINED WIND SPEED IS 125 KT WITH GUSTS TO 150 KT. THE EYE DIAMETER IS ABOUT 20 NM. LATEST SATELLITE IMAGERY SHOWS THAT RICK HAS WEAKEN SLIGHTLY OVER THE PAST SEVERAL HOURS AS INDICATED BY WARMING CLOUD TOPS SURROUNDING THE EYE...AND IS MOST EVIDENT OVER THE W QUADRANT. THIS WAS DUE TO THE INTRUSION OF DRY INTO THE W SIDE OF THE CYCLONE. VERTICAL WIND SHEAR IS FORECAST TO INCREASE ALONG WITH FURTHER INTRUSION OF DRY OVER THE NEXT 48 HOURS...BUT RICK IS STILL EXPECTED TO APPROACH THE SOUTHERN BAJA CALIFORNIA PENINSULA AS A HURRICANE. RICK IS CURRENTLY BEING STEERED BY A MIDDLE/UPPER LEVEL RIDGE LOCATED OVER MEXICO. NUMEROUS STRONG CONVECTION IS LOCATED WITHIN 90 NM OF THE CENTER IN THE E SEMICIRCLE AND WITHIN 60 NM OF THE CENTER IN THE NW QUADRANT. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP5/WTPZ25 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... A TROPICAL WAVE HAS MOVED INTO THE FAR EASTERN PORTION OF THE AREA ALONG 82W N OF 04N TO ACROSS WESTERN PANAMA AND INTO THE SW CARIBBEAN. THE WAVE IS MOVING W ABOUT 12 KT. CONVECTION EARLIER NOTED HAS DISSIPATED...AND ONLY CONVECTION OCCURRING IS JUST TO THE W OF THE WAVE ALONG THE ITCZ. A TROPICAL WAVE IS ALONG 124W FROM 06N TO 16N MOVING W 10 KT. THE WAVE IS WEAK AND ASSOCIATED CONVECTION IS DESCRIBED BELOW WITH THE ITCZ. ...ITCZ... THE AXIS OF THE INTERTROPICAL CONVERGENCE ZONE IS CENTERED ALONG 9N84W TO 8N92W TO 13N104W...THEN RESUMES AT 13N111W TO 12N120W TO 13N130W TO 11N140W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 120 NM S OF THE AXIS BETWEEN 106W-110W. SCATTERED MODERATE CONVECTION IS WITHIN 120 NM S OF THE AXIS BETWEEN 83W-89W...FROM 8N-12N BETWEEN 119W-121W...AND WITHIN 180 NM S OF THE AXIS BETWEEN 121W-126W. ...DISCUSSION... W OF 115W... A DEEP LAYER TROUGH IS LOCATED N OF 20N W OF 1232 WITH A MEAN AXIS ROUGHLY FROM 32N123W TO 26N130W TO 23N140W. THE TROUGH IS ADVANCING QUICKER N OF 27N...WHILE BEGINNING TO LAG S OF 27N. MODERATE SUBSIDENCE SUPPORTING DRY AND STABLE CONDITIONS COVERS THE AREA N OF 16N. PATCHES OF BROKEN TO OVERCAST STRATOCUMULUS CLOUDS MOVING WSW ARE SEEN OVER THIS AREA. A DEEP LAYER RIDGE W OF THE AREA IS BUILDING EASTWARD TOWARDS 140W. WNW UPPER FLOW IS PRESENT W OF THE TROUGH AND AHEAD OF THE RIDGE. THE TROUGH IS FORECAST TO BECOME ORIENTED ALONG 117W/118W N OF 18N IN 48 HOURS...AND WILL ACT TO TURN RICK IN A MORE NORTHERLY DIRECTION AND THEN TO THE NE INTO MEXICO. GENERALLY MODERATE EASTERLY FLOW ALOFT IS LOCATED OVER THE TROPICS S OF ABOUT 15N. AT THE SURFACE A 1021 MB HIGH IS LOCATED NEAR 31N136W WITH A RIDGE SE TO NEAR 26N121W. A COLD FRONT IS JUST NW OF THE AREA CROSSING 32N140W. THE FRONT IS FORECAST TO WEAKEN OVER THE NEXT 24-48 HOURS AS MAIN ENERGY SOURCE STAYS FAR TO THE N. LONG PERIOD NW SWELLS OF UP TO 9 FT ARE FORECAST TO MIGRATE SE INTO THE FAR NW PORTION BY MON NIGHT. E OF 115W... WINDS ALOFT ARE GENERALLY NORTHEASTERLY BETWEEN 90W AND 100W AND BECOME MORE EASTERLY E OF 90W INTO CENTRAL AND SOUTH AMERICA. GAP WINDS... A STORM WARNING IS CURRENTLY IN EFFECT FOR THE GULF OF TEHUANTEPEC...BUT IS EXPECTED TO TAPER OFF INTO A GALE WARNING IN 12 HOURS AND CONTINUE THROUGH THE NEXT 24 HOURS. $$ AGUIRRE