000 AXPZ20 KNHC 170917 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC SAT OCT 17 2009 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0900 UTC. ...SPECIAL FEATURE... HURRICANE RICK WAS CENTERED NEAR 13.9N 102.0W AT 0900 UTC OR ABOUT 260 MILES...400 KM SW OF ACAPULCO MEXICO MOVING WNW AT 10 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 960 MB. MAXIMUM SUSTAINED WINDS HAVE INCREASED TO 100 KT WITH GUSTS TO 120 KT. SEE THE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP5/WTPZ25 KNHC FOR MORE DETAILS. NUMEROUS STRONG CONVECTION IS WITHIN 130 NM OF THE CENTER ALSO WIDELY SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION IS ELSEWHERE WITHIN 360 NM OF THE CENTER. ATMOSPHERIC CONDITIONS APPEAR FAVORABLE FOR RICK TO CONTINUE TO UNDERGO INTENSIFICATION UNDER A LOW SHEAR ENVIRONMENT ALONG WITH VERY CONDUCIVE SEA SURFACE TEMPERATURES THROUGH THE NEXT 48 HOURS AS IT TRACKS W-NW. ...TROPICAL WAVE... A TROPICAL WAVE ALONG 116W/117W FROM 07N TO 16N IS MOVING WEST AT ABOUT 13 KT. CONVECTION HAS DIMINISHED WITH ONLY WIDELY SCATTERED MODERATE CONVECTION NEAR THE WAVE AXIS WITHIN THE ITCZ. ...ITCZ... THE AXIS OF THE INTERTROPICAL CONVERGENCE ZONE IS CENTERED ALONG THE LINE...07N77W TO 08N105W TO 08N115W TO 14N125W TO 07N140W. SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION IS WITHIN 45 NM EITHER SIDE OF THE ITCZ AXIS WEST OF 115W. ...DISCUSSION... DEEP LAYER TROUGH IS OVER THE FAR NORTHWEST PART OF THE AREA NW OF A LINE THROUGH 32N136W TO 29N140W. ASSOCIATED COLD FRONT IS ALONG ABOUT THE SAME LINE. MULTI LEVEL CLOUDS WITH SOME SHOWERS IS IN A NARROW BAND ABOUT 30 NM WIDE ALONG THE FRONT. THE TROUGH IS FORECAST TO WEAKEN AND BE ABSORBED BY WESTERLIES NORTH OF THE AREA LATER TODAY. MAINLY UPPER TROUGH IS OVER THE CENTRAL PART OF THE PACIFIC AREA WITH AN AXIS ALONG A LINE FROM 23N115W TO THE ITCZ AT 140W. WITHIN 600 NM NORTHWEST OF THIS LINE THE ATMOSPHERE IS DRY AND CLOUD FREE IN THE MIDDLE AND UPPER LEVELS. OVERCAST STRATOCUMULUS COVERS THE AREA NORTH OF 18N WEST OF 115W AND SOUTH OF 18N SCATTERED STRATOCUMULUS IS OBSERVED. CONVECTION IS OBSERVED NEAR THE TROUGH AXIS AND IS MENTIONED IN THE ITCZ SECTION. A CYCLONIC CIRCULATION IS CENTERED JUST OFFSHORE SOUTHERN CALIFORNIA NEAR 31N118.5W. THE ASSOCIATED CIRCULATION EXTENDS OUT ABOUT 200 NM. THE AREA IS DRY AND CLOUD FREE IN THE MIDDLE AND UPPER LEVELS WITH OVERCAST STRATOCUMULUS IN THE LOWER LEVELS. A TROUGH IS OVER NORTHERN CENTRAL AMERICA AND EXTENDS OVER THE PACIFIC NORTH OF 10N EAST OF 91W. THIS AREA IS MOSTLY DRY AND CLOUD FREE IN THE MIDDLE AND UPPER LEVELS AND ALSO THE LOWER LEVELS. ISOLATED CONVECTION OVER THE LAND HAS DIMINISHED. ISOLATED MODERATE CONVECTION MAY FORM IN THIS AREA. REMAINDER OF THE MIDDLE AND UPPER LEVELS IS UNDER BROAD ANTICYCLONIC FLOW. BESIDES THE COLD FRONT OVER THE FAR NORTHWEST PART A MODERATE RIDGE IS NORTH OF 16N WEST OF 112W. ELSEWHERE BESIDES THE HURRICANE A BROAD TROUGH IS OBSERVED AT THE SURFACE. GAP WINDS...A COLD FRONT CURRENTLY LIES OVER THE GULF OF MEXICO FROM TAMPA BAY TO NE MEXICO. THE DEEP LAYER MID LATITUDE TROUGH SUPPORTING THIS COLD FRONT WILL AMPLIFY OVER THE GULF OF MEXICO SAT AND SEND THE STRONG COLD FRONT THROUGH THE BAY OF CAMPECHE. THE NORTHERLY FLOW WILL BEGIN FUNNELING THROUGH THE ISTHMUS OF TEHUANTEPEC BY SAT MORNING...MAKING ITS WAY OVER SEA SURFACE TEMPERATURES NEAR 30 CELSIUS. STRONG WINDS ALOFT WILL QUICKLY MIX TO THE SURFACE. WINDS ARE EXPECTED TO REACH GALE FORCE BY SAT EVENING WITH SIGNIFICANT WAVE HEIGHTS REACHING 15 FT. $$ LL