000 AXNT20 KNHC 061754 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT THU JUN 06 2013 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...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...SPECIAL FEATURES... TROPICAL STORM ANDREA IS CENTERED NEAR 29.0N 83.6 AT 06/1800 UTC OR ABOUT 30 NM WSW OF CEDAR KEY FLORIDA...AND 85 NM ESE OF APALACHICOLA FLORIDA MOVING NE AT 15 KT. ESTIMATED CENTRAL PRESSURE IS 994 MB. MAXIMUM SUSTAINED WIND SPEED IS 50 KT WITH GUSTS TO 60 KT. ONE MAIN RAIN BAND IS WRAPPING AROUND THE EASTERN SIDE OF THE CENTER. NUMEROUS MODERATE/SCATTERED STRONG CONVECTION IS FROM 19N-24N BETWEEN 85W-87W...AND FROM 24N-27N BETWEEN 82W-85W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS OVER CENTRAL FLORIDA FROM 27N-30N BETWEEN 78W-83W. ANDREA SHOULD MAKE LANDFALL SOMEWHERE IN THE BIG BEND OF FLORIDA LATER TODAY AND CONTINUE UP THE EASTERN SEABOARD TOMORROW AND SATURDAY. SEE LATEST NHC INTERMEDIATE PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS MIATCPAT1/WTNT31 KNHC AND THE FULL FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMAT1/WTNT21 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... ACTIVE TROPICAL WAVE EXTENDS FROM 18N45W TO 9N46W MOVING WEST NEAR 12 KT. A WEAK 1014 MB SURFACE LOW IS ANALYZED ALONG THE WAVE AXIS NEAR 14N46W WHERE CYCLONIC FLOW IS MOST CONCENTRATED. THE WAVE COINCIDES WITH A NORTHWARD SURGE OF DEEP LAYER MOISTURE EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. NUMEROUS MODERATE/SCATTERED STRONG CONVECTION IS FROM 12N-15N BETWEEN 43W- 46W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE COAST OF GUINEA-BISSAU NEAR 12N16W TO 6N19W. THE ITCZ BEGINS NEAR 6N19W AND CONTINUES ALONG 7N31W 6N39W. SCATTERED MODERATE CONVECTION IS FROM 2N-5N BETWEEN 14W-19W...AND FROM 3N-5N BETWEEN 22W-25W. ...DISCUSSION... GULF OF MEXICO... TROPICAL STORM ANDREA IN THE NE CORNER OF THE GULF OF MEXICO IS PROVIDING WET AND WINDY CONDITIONS ACROSS THE EASTERN GULF. NUMEROUS STRONG SHOWERS/THUNDERSTORMS ARE IN THE SE GULF FROM 22N-24N BETWEEN 85W-87W...AND FROM 24N-27N BETWEEN 82W-85W. NUMEROUS SHOWERS/ISOLATED THUNDERSTORMS ARE OVER THE FLORIDA PENINSULA NORTH OF 26N EAST OF 85W. SEE SPECIAL FEATURES FOR MORE DETAILS. AN UPPER LEVEL TROUGH IS ALONG 89W...WHICH IS PROVIDING DIFFLUENT ALOFT OVER THE FAR EASTERN GULF NEAR ANDREA. THE REMAINDER OF THE BASIN IS COVERED BY DRY AIR ALOFT...WHICH IS HELPING PROVIDE FAIR CONDITIONS AND MOSTLY CLEAR SKIES. ANDREA IS EXPECTED TO MAKE LANDFALL LATER TODAY AND QUICKLY MORE NE OF THE AREA. BROAD SURFACE TROUGHING WILL LIKELY REMAIN OVER THE GULF IN THE WAKE OF THE STORM. SURFACE RIDGING WILL BUILD BACK IN BY THE END OF THE WEEKEND. CARIBBEAN SEA... THE FAR NW CORNER OF THE CARIBBEAN IS EXPERIENCING IMPACTS FROM TROPICAL STORM ANDREA. A CLUSTER OF SHOWERS/THUNDERSTORMS IS FROM 19N-21N BETWEEN 85W-87W. A FEW ISOLATED SHOWERS/THUNDERSTORMS ARE ALSO ALONG A LINE FROM 17N83W TO 12N81W...AS WELL AS NORTH OF PANAMA FROM 9N-11N BETWEEN 81W-83W. THE REMAINDER OF THE CARIBBEAN IS UNDER MOSTLY CLEAR SKIES...WHICH IS THE RESULT OF MODERATE DRY AIR ALOFT BETWEEN AN UPPER LEVEL RIDGE OVER THE WESTERN CARIBBEAN...AND AN UPPER LEVEL TROUGH OVER THE EASTERN CARIBBEAN. VISIBLE SATELLITE IMAGERY ALONG WITH SURFACE OBSERVATIONS ALSO INDICATE A LARGE AREA OF DUST OVER THE CENTRAL AND EASTERN PORTIONS OF THE BASIN. TRADEWIND FLOW OF 20 KT DOMINATES THE FLOW AT THE SURFACE. LITTLE CHANGE IS EXPECTED OVER THE NEXT 24 HOURS. HISPANIOLA... NO SHOWERS ARE ACROSS HISPANIOLA AT THIS TIME. SEVERAL STATIONS OVER THE ISLAND ARE REPORTING DUST...WHICH WILL LIKELY LIMIT AFTERNOON CONVECTION. SOME MAY STILL DEVELOP...BUT WILL BE LESS THAN NORMAL. LITTLE CHANGE IN THE SYNOPTIC PATTERN IS EXPECTED OVER THE NEXT COUPLE OF DAYS WITH TYPICAL AFTERNOON CONVECTION LIKELY. ATLANTIC OCEAN... UPPER LEVEL DIFFLUENCE IS ACROSS THE WESTERN ATLC BETWEEN AN UPPER LEVEL TROUGH OVER THE EASTERN GULF OF MEXICO NEAR T.S. ANDREA...AND AN UPPER LEVEL RIDGE ALONG 75W. SCATTERED SHOWERS ARE WEST OF 76W...AS WELL AS NORTH OF 29N BETWEEN 67W-73W. A LARGE CLUSTER OF THUNDERSTORMS IS ALSO FROM 27N-29N BETWEEN 79W- 80W. ACTIVITY WILL LIKELY CONTINUE OFF THE NE COAST OF FLORIDA AS ANDREA MOVES OVER NE FLORIDA AND UP THE EASTERN UNITED STATES COAST. THE REMAINDER OF THE ATLC...BOTH CENTRAL AND EASTERN PORTIONS...IS DOMINATED BY A BROAD SURFACE RIDGE ANCHORED BY A 1029 MB HIGH NEAR 36N42W. ALOFT...A WEAK UPPER LEVEL LOW IS NEAR 23N56W...BUT IS NOT CAUSING ANY ACTIVE WEATHER. A BROAD UPPER RIDGE DOMINATES THE PATTERN ALONG 30W SUPPORTING THE BROAD SURFACE RIDGE. VISIBLE SATELLITE IMAGERY INDICATES A LARGE AREA OF SAHARAN DUST EXTENDS EAST OF THE TROPICAL WAVE NEAR 46W SOUTH OF 24N. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON