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000 FXUS62 KTBW 221820 AFDTBW AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TAMPA BAY RUSKIN FL 120 PM EST SUN NOV 22 2009 .SHORT TERM (TONIGHT THROUGH TUESDAY)... A BROAD AREA OF LOW PRESSURE IS LOCATED ALONG THE CENTRAL GULF COAST THIS AFTERNOON...WITH A COLD FRONT VERY SLOWLY ADVANCING THROUGH THE EASTERN GULF WATERS. SHOWERS AND THUNDERSTORMS ARE FOUND AHEAD OF THIS BOUNDARY...EXTENDING INTO NORTH CENTRAL FLORIDA. THE UPPER LOW CURRENTLY OVER EXTREME NORTHERN ALABAMA IS QUICKLY ADVANCING NORTH-NORTHEASTWARD THIS AFTERNOON/EVENING AND AS THIS SYSTEM TO OUR WEST LOSES ITS UPPER LEVEL SUPPORT...THE SURFACE LOW WILL CONTINUE TO WEAKEN AND THE FRONT WILL EVENTUALLY STALL AS IT MOVES OVER THE PENINSULA. EXPECT THERE TO BE ENOUGH MOISTURE AND INSTABILITY OVERNIGHT WITH THE FRONT FOR A CHANCE OF SHOWERS TO CONTINUE. DRIER AIR MOVING IN OVER THE FL PANHANDLE HOWEVER MAY LIMIT CHANCES UP IN OUR NORTHERN COUNTIES AND OFFSHORE. ON MONDAY THE SURFACE LOW CONTINUES TO PUSH UP ALONG THE MID ATLANTIC COAST AND THE FRONTAL BOUNDARY REMAINS SOMEWHERE OVER CENTRAL FLORIDA. WHERE THE BOUNDARY ACTUALLY ENDS UP IS WHERE POPS WILL BE FOCUSED...AND BELIEVE THIS SHOULD BE SOMEWHERE BETWEEN THE TAMPA BAY AREA AND FORT MYERS (EACH MODEL RUN SEEMS TO BE PUSHING IT FURTHER NORTHWARD). DRIER AIR TO THE NORTH WILL LIMIT RAIN POTENTIAL AND HAVE DROPPED POPS FOR LEVY AND CITRUS COUNTIES TO ACCOUNT FOR THIS. AN UPPER TROUGH DIGS DOWN INTO THE CENTRAL PLAINS ON TUESDAY...AND SOME ENERGY MOVES AROUND THE BASE OF THIS TROUGH INTO THE CENTRAL GULF. REMNANTS OF THE FRONTAL BOUNDARY WILL STILL BE HANGING AROUND THE PENINSULA AS WELL...SO WILL CALL FOR A CONTINUED CHANCE OF RAIN. HAVE KEPT POPS AT 30% FOR NOW DUE TO UNCERTAINTY ON THE EXACT LOCATION OF THE BOUNDARY. WITHOUT ANY REAL COLD PUSH BEHIND THIS FRONT...TEMPS WILL CONTINUE TO RUN ABOUT 4-6 DEGREES ABOVE NORMAL EVEN WITH THE ADDED CLOUD COVER. .LONG TERM (TUESDAY NIGHT THROUGH SUNDAY)... MOIST AND UNSETTLED WEATHER FEATURES MID WEEK THEN DRYING AND COOLER BY NEXT WEEKEND. EXTENDED MODELS COMING IN BETTER AGREEMENT ON OVERALL FEATURES BUT EXACT TIMING AND FINAL PLACEMENT STILL UNCLEAR. ECMWF/CANADIAN/NAM AND DGEX ARE THE SLIGHTLY SLOWER SOLUTIONS WITH MID WEEK SYSTEM WHILE GFS AND NOGAPS ARE SLIGHTLY FASTER. WILL GO WITH BLEND AND EXPECT MID TO UPPER TROUGH TO OUR WEST WITH DEEP SOUTHWEST FLOW BRINGING AMPLE GULF MOISTURE TO THE AREA WHILE EJECTING MULTIPLE VORTICITY MAXES THE REGION AS A SURFACE FRONT STALLS OVER THE SOUTH CENTRAL FLORIDA PENINSULA. WEAK LOW PRESSURE AREA MAY FORM SOMEWHERE ALONG FRONT...BUT ALL FEATURES TO COMBINE IN UNSTABLE ENVIRONMENT TO PRODUCE 30 TO 50 POPS AREAWIDE TUESDAY NIGHT-WEDNESDAY NIGHT. HAVE KEPT HIGHEST POPS OVER SOUTHERN AREAS CLOSER TO EXPECTED HIGHEST MEAN LAYER MOISTURE AND BEST LOW LEVEL CONVERGENCE. AS FEATURES UNFOLD GRIDS WILL BE TAILORED TO THE METEOROLOGICALLY FAVORED AREAS. TEMPS TO HOLD SLIGHTLY ABOVE NORMAL THROUGH MID WEEK. DIGGING UPPER LONGWAVE TROUGH TO PUSH ALL ACTIVITY TO THE EAST WITH COLD FRONT CLEARING THROUGH THE REGION THANKSGIVING DAY BRINGING AN END TO THE RAIN. TEMPS BEGIN TO FALL BEHIND THE FRONT. TO END THE WEEK AND INTO THE WEEKEND NW...FLOW ALOFT AND COOL AND DRY HIGH PRESSURE BUILDING INTO THE REGION TO KEEP TEMPS 5 TO 10 DEGREES BELOW NORMAL MOST OF THE AREA WITH THE COOLEST TEMPS FELT OVER THE NATURE COAST. && .AVIATION... GENERALLY VFR CONDITIONS ARE EXPECTED THIS AFTERNOON INTO TONIGHT BUT CONTINUE TO HAVE SCT SHRA WITH A FEW EMBEDDED ISOLD TSRA OVER THE E GULF MOVING ASHORE WITH LCL MVFR/IFR CIGS/VSBYS AND GUSTY WINDS IN CONVECTION THIS AFTERNOON INTO TONIGHT. ALSO TOWARDS MORNING AREAS OF BR TO REDEVELOP WITH MVFR CIGS/VSBYS POSSIBLE. && .MARINE... A COLD FRONT IN THE EASTERN GULF THIS AFTERNOON IS HELPING TO MAINTAIN SHOWERS AND THUNDERSTORMS OVER OUR COASTAL WATERS...AS WELL AS SLIGHTLY STRONGER SOUTHERLY WINDS GENERALLY NORTH OF TAMPA BAY. THIS FRONTAL BOUNDARY WILL SLOWLY SHIFT EAST OVERNIGHT INTO EARLY MONDAY...AND AS IT DOES...WINDS WILL SHIFT TO THE WEST AND EVENTUALLY NORTH BY MONDAY MORNING. THE BOUNDARY WEAKENS CONSIDERABLY HOWEVER...SO DON`T EXPECT SPEEDS TO BE ALL THAT MUCH MORE THAN 10KTS. WITH THIS DISSIPATING FRONTAL BOUNDARY HANGING OUT OVER THE AREA FOR THE NEXT FEW DAYS (IT`S EXACT LOCATION IS A LITTLE UNCERTAIN AT THIS TIME)...EXPECT WINDS TO BE SOMEWHAT VARIABLE...BUT GENERALLY FROM THE NORTHEAST AROUND 10KTS OR LESS THROUGH MID-WEEK. && .FIRE WEATHER... ENOUGH MOISTURE HANGS UP OVER THE AREA FOR THE NEXT FEW DAYS THAT THERE WILL BE NO FIRE WEATHER ISSUES IN THE SHORT TERM. && .PRELIMINARY POINT TEMPS/POPS... TPA 67 81 64 79 / 30 20 10 30 FMY 69 84 66 82 / 20 30 20 30 GIF 66 82 63 80 / 30 30 20 30 SRQ 67 80 64 79 / 30 30 20 30 BKV 62 80 57 79 / 30 20 10 30 SPG 67 78 67 77 / 30 20 20 30 && .TBW WATCHES/WARNINGS/ADVISORIES... FL...NONE. GULF WATERS...NONE. && $$ SHORT TERM/MARINE/FIRE WEATHER...23/MCNATT LONG TERM/AVIATION...25/DAVIS