000 AXNT20 KNHC 242358 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT SUN OCT 24 2010 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS OF SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND RADAR. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2330 UTC. ...SPECIAL FEATURE... HURRICANE RICHARD IS NEAR 17.2N 88.2W AT 25/0000 UTC OR ABOUT 17 NM S OF BELIZE CITY. RICHARD IS MOVING WNW AT 9 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 981 MB. MAXIMUM SUSTAINED WIND SPEED IS 80 KT WITH GUSTS TO 95 KT. SEE LATEST NHC INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT4/ WTNT34 KNHC...AND THE FULL FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT4/WTNT24 KNHC FOR MORE DETAILS. WEAKENING IS EXPECTED ONCE RICHARD MOVES INLAND. NUMEROUS STRONG CONVECTION IS CURRENTLY NEAR THE CENTER OF RICHARD FROM 17N-19N BETWEEN 87W-89W. NUMEROUS MODERATE/SCATTERED STRONG CONVECTION IS FROM 16N-21N BETWEEN 85W-91W. SCATTERED MODERATE/STRONG CONVECTION IS S OF THE CIRCULATION ACROSS MUCH OF CENTRAL AMERICA S OF 16N BETWEEN 84W-87W....AND IN THE SW CARIBBEAN FROM 11N-18N BETWEEN 77W-83W. ...TROPICAL WAVE... TROPICAL WAVE EXTENDS FROM 25N34W TO 17N37W MOVING NW 10-15 KT. THE LAST VISIBLE SATELLITE IMAGES OF THE DAY SHOWED BROAD LOW-LEVEL CYCLONIC FLOW ABOUT THE WAVE AXIS AND CONCENTRATED NEAR A 1011 MB LOW ANALYZED ON THE WAVE AXIS NEAR 21N35W. TOTAL PRECIPITABLE WATER IMAGERY ALSO INDICATES A LARGE AREA OF DEEP LAYER MOISTURE ACROSS THE ERN TROPICAL ATLC WITH MAXIMUM VALUES NEAR THE WAVE. SCATTERED MODERATE/STRONG CONVECTION IS FROM 17N-26N BETWEEN 30W-39W. THE WAVE IS CURRENTLY BEING SHEARED BY SWLY FLOW ALOFT BETWEEN AN UPPER LEVEL LOW CENTERED NEAR 20N41W AND AN UPPER LEVEL RIDGE OVER THE FAR E ATLC. WITH THE STRONG SHEAR FORECAST TO PERSIST...LITTLE DEVELOPMENT OF THE SYSTEM IS EXPECTED OVER THE NEXT COUPLE OF DAYS. ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 5N5W 5N15W 3N24W 7N33W. A SURFACE TROUGH EXTENDS N OF THE AXIS FROM A 1005 MB LOW OVER MAURITANIA ALONG 14N14W TO 7N23W. SCATTERED MODERATE/STRONG CONVECTION IS FROM 7N-12N BETWEEN 10W-16W...AND FROM 5N-9N BETWEEN 22W-26W. ISOLATED MODERATE/STRONG CONVECTION IS WITHIN 30NM OF THE ITCZ AXIS BETWEEN 20W-35W. ...DISCUSSION... THE GULF OF MEXICO... A BROAD MID-UPPER LEVEL RIDGE IS ACROSS THE GULF OF MEXICO EXTENDING FROM THE ANTI-CYCLONIC OUTFLOW OF HURRICANE RICHARD IN THE NW CARIBBEAN. THE UPPER RIDGE SUPPORTS SURFACE RIDGING ACROSS THE BASIN ANCHORED BY A 1025 MB HIGH BETWEEN BERMUDA AND SOUTH CAROLINA NEAR 33N70W. ELY WINDS OF 15-20 KT ARE ACROSS THE ERN HALF OF THE BASIN BECOMING SE-S AND DECREASING TO 10-15 KT ACROSS THE WRN HALF OF THE BASIN. WATER VAPOR IMAGERY INDICATES A MOSTLY DRY AIR MASS IS IMPACTING THE AREA SUPPORTING GENERALLY FAIR WEATHER THROUGHOUT THE GULF. HOWEVER...A JETSTREAK BETWEEN THE UPPER LEVEL RIDGE AND AN UPPER LEVEL TROUGH MOVING ACROSS THE CENTRAL UNITED STATES IS SUPPORTING AN AREA OF SCATTERED SHOWERS/THUNDERSTORMS IN THE N CENTRAL GULF N OF 28N BETWEEN 86W-90W. A FEW ISOLATED SHOWERS ARE ALSO NOTED ACROSS PORTIONS OF S FLORIDA. EXPECT SHOWER ACTIVITY TO INCREASE ACROSS THE SRN PORTIONS OF THE BASIN AS HURRICANE RICHARD MOVES WWD. THE CARIBBEAN SEA... HURRICANE RICHARD IS ABOUT TO MAKE LANDFALL ALONG THE BELIZE COAST NEAR BELIZE CITY...AND IS BRINGING HEAVY SHOWERS/THUNDERSTORMS TO BELIZE AND THE YUCATAN PENINSULA. SEE SPECIAL FEATURES ABOVE FOR MORE DETAILS. THE CIRCULATION OF RICHARD IS ALSO DRAWING MOISTURE NWD ACROSS THE CENTRAL CARIBBEAN PRODUCING SCATTERED SHOWERS/THUNDERSTORMS FROM 11N-18N BETWEEN 77W-83W...AS WELL AS ACROSS MUCH OF CENTRAL AMERICA FROM PANAMA TO HONDURAS. A FEW ISOLATED SHOWERS ARE ALSO ACROSS ERN CUBA. RICHARD IS UNDER THE INFLUENCE OF A BROAD UPPER RIDGE THAT IS CENTERED JUST W OF JAMAICA. THE ERN CARIBBEAN IS EXPERIENCING MOSTLY FAIR CONDITIONS UNDER A DRY AND STABLE AIR MASS. HOWEVER...A FEW ISOLATED SHOWERS ARE NOTED N OF VENEZUELA EMBEDDED WITHIN TRADEWIND FLOW. EXPECT CONTINUED SHOWER ACTIVITY ACROSS THE WRN HALF OF THE BASIN AS RICHARD MOVES WWD ACROSS THE YUCATAN PENINSULA. THE ATLANTIC OCEAN... SURFACE RIDGING CENTERED BETWEEN BERMUDA AND THE CAROLINAS IS PRODUCING FAIR WEATHER ACROSS THE FAR SW N ATLC. HOWEVER...A SHORTWAVE UPPER LEVEL TROUGH IS ALONG 66W SUPPORTING A SURFACE TROUGH...REMNANT FRONTAL BOUNDARY...FROM 32N46W TO 25N61W CONTINUING AS A SHEAR LINE TO 24N74W. UPPER LEVEL DIFFLUENCE ALOFT WITH MOIST SWLY FLOW BETWEEN THIS UPPER TROUGH AND AN UPPER LEVEL RIDGE TO THE E WITH AXIS ALONG 60W IS ENHANCING SCATTERED SHOWERS WITHIN 60 NM OF THE TROUGH/SHEAR LINE AXIS WITH ISOLATED SHOWERS ACROSS THE SE BAHAMAS. FARTHER E...AN UPPER LEVEL LOW CENTERED NEAR 20N41W IS SUPPORTING A SURFACE TROUGH ALONG 16N44W TO 9N49W. ISOLATED SHOWERS/THUNDERSTORMS ARE FROM 6N-16N BETWEEN 37W-45W. THE UPPER LOW IS ALSO ENHANCING CONVECTION NEAR A TROPICAL WAVE. SEE TROPICAL WAVE SECTION FOR MORE DETAILS. TO THE N...SURFACE RIDGING DOMINATES ANCHORED BY A 1026 MB HIGH CENTERED JUST E OF THE AZORES ISLANDS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON