Area Forecast Discussion
Issued by NWS Knoxville/Tri Cities, TN

Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS64 KMRX 210906 AFDMRX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MORRISTOWN TN 400 AM EST SUN DEC 21 2014 .SHORT TERM (TODAY AND TONIGHT)...SURFACE HIGH PRESSURE WILL EXTEND INTO THE AREA TODAY. EXPECT THE REMAINING CLOUD COVER TO BREAK UP ALLOWING DECENT AMOUNT OF SUNSHINE TODAY. WEAK SHORT WAVE ENERGY WILL MOVE INTO THE REGION TONIGHT. BETTER LIFT SHOULD STAY TO OUR SOUTH AND EAST. MOISTURE WILL BE LIMITED...AND RATHER SHALLOW...SO WILL JUST CARRY PATCHY DRIZZLE AND SLIGHT CHANCE TO CHANCE POPS FOR LIGHT RAIN. THERMAL PROFILES SUGGEST ALL LIQUID PRECIP FOR TONIGHT. JUST MINOR ADJUSTMENTS TO MAV TEMPS...INCLUDING TWEAKING MOST MIN TEMPS UP SLIGHTLY FOR TONIGHT GIVEN EXPECTED CLOUD COVER. .LONG TERM (MONDAY THROUGH SATURDAY)...MODELS STILL INDICATE SUNDAY NIGHT SHORT WAVE WILL BE IN THE PROCESS OF MOVING AWAY TO THE EAST ON MONDAY ALLOWING FOR A DRIER AFTERNOON WITH PERHAPS A BREAK OR TWO OF SUNSHINE HERE AND THERE ESPECIALLY WEST. WILL BE AWAITING THE STRENGTHENING MIDDLE AMERICA STORM SYSTEM MONDAY NIGHT INTO TUESDAY WHICH FEATURES A STRENGTHENING AND MOISTENING SOUTHERLY FLOW ACROSS THE EASTERN UNITED STATES. AS THIS OCCURS THE WIND FIELD WILL RAMP UP RATHER DECENTLY AS THE PRESSURE GRADIENT TIGHTENS. THIS STRENGTHENING SOUTHERLY FLOW WILL BRING A WARM FRONT ACROSS THE SOUTHERN APPALACHIAN REGION MONDAY NIGHT SO THERE COULD BE A FEW SHOWERS WITH THIS FEATURE MAINLY ACROSS WESTERN SECTIONS. THE STRONG WIND COMPONENT ACROSS THE APPALACHIANS WILL LEAD TO A NICE DOWNSLOPING PATTERN ACROSS MUCH OF SOUTHWEST VIRGINIA...NORTHEAST AND PART OF CENTRAL EAST TENNESSEE WHERE THE CHANCE OF RAIN WILL BE LOWER DUE TO THE TYPICAL WARMING AND DRYING OF THE LOWER ATMOSPHERE DUE TO THE FORCED FLOW OVER THE TERRAIN. A SHARP COLD FRONT WILL FORM OUT ACROSS THE MISSISSIPPI VALLEY ON TUESDAY AND THE FRONT WILL TAKE ITS SWEET TIME MAKING EASTWARD PROGRESS WHICH WILL KEEP THE FORECAST AREA IN THE SYSTEM`S WARM SECTOR TUESDAY THROUGH TUESDAY NIGHT. THE MODELS CONTINUE TO INDICATE SOME INSTABILITY AHEAD OF THE FRONT SO ADDED THE CHANCE FOR SOME THUNDERSTORMS TO FORM IN THE EXPECTED WIDESPREAD PATTERN OF SHOWERS AHEAD OF THE FRONT. THE FRONT MOVES SLOWLY EAST ACROSS THE SOUTHERN APPALACHIANS TUESDAY NIGHT INTO WEDNESDAY MORNING AND WILL BE A LITTLE SLOWER THAN PREVIOUSLY EXPECTED. THEREFORE ANY TRANSITION TO SOME LIGHT SNOW SHOWERS ON THE BACK SIDE OF THE AMPLIFIED SYSTEM LOOKS LIKE IT WILL HOLD OFF UNTIL WEDNESDAY EVENING. FROM THIS VANTAGE POINT THE SNOW EVENT DOESN`T LOOK VERY IMPRESSIVE WITH A FEW LIGHT SNOW SHOWERS OR FLURRIES IN THE GREAT VALLEY WITH A LITTLE BETTER POSSIBILITY OF SNOWFALL IN THE HIGHER TERRAIN...MAINLY ABOVE 3000 FEET WHERE SOME MINOR ACCUMULATION MAY OCCUR WEDNESDAY NIGHT. THERE STILL MAY BE A FEW SNOW SHOWERS ONGOING THROUGH LATE MORNING ON CHRISTMAS DAY ACROSS SOUTHWEST VIRGINIA AND NORTHEAST TENNESSEE BUT THE PRECIP SHOULD BE OVER IN THIS AREA BY EARLY AFTERNOON. AGAIN...STILL LOOKS LIKE THERE COULD BE SOME SUNSHINE RETURNING ACROSS WESTERN PARTS OF THE FORECAST AS THE DAY PROGRESSES. MODEL SOLUTIONS DIVERGE TO A CERTAIN DEGREE FOR THE END OF THE FORECAST ON FRIDAY AND SATURDAY SO WE WILL HAVE TO WAIT ON FUTURE RUNS TO GET A BETTER IDEA FOR THIS PERIOD. FOR NOW ANOTHER UPPER TROUGH WILL BE ON THE APPROACH FRIDAY INTO SATURDAY WITH MOISTENING AND INCREASING LIFT WEIGHTED MORE TOWARD FRIDAY NIGHT INTO SATURDAY AS AN ASSOCIATED COLD FRONT MOVES ACROSS THE REGION. && .PRELIMINARY POINT TEMPS/POPS... CHATTANOOGA AIRPORT, TN 53 40 56 46 / 10 20 20 20 KNOXVILLE MCGHEE TYSON AIRPORT, TN 50 38 55 43 / 0 20 20 10 OAK RIDGE, TN 49 37 55 44 / 0 20 20 10 TRI CITIES AIRPORT, TN 47 35 51 37 / 0 30 40 0 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$

USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.