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 282020 AFDMRX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MORRISTOWN TN 320 PM EST SAT FEB 28 2015 .SHORT TERM...
-- Changed Discussion --
(TONIGHT THROUGH SUNDAY NIGHT)... CLOUDS TO OUR WEST HAVE BEEN DISSIPATING BEFORE MAKING IT INTO OUR AREA...KEEPING PLENTY OF SUNSHINE AND ALLOWING TEMPS TO RISE INTO THE 40S IN MOST SPOTS. WITH THE LACK OF CLOUDS...TEMPS WILL LIKELY DROP OFF QUICKLY AFTER SUNSET. HOWEVER...ADVECTION OF WARM MOIST AIR AT THE 925-850 MB LEVEL WILL COMMENCE LATER TONIGHT AS THE SE FLOW AT THAT LEVEL INCREASES TO 20-30 KTS. THIS WILL CREATE A STRONG INVERSION AND HELP TEMPERATURES LEVEL OFF OR RISE SLIGHTLY LATE TONIGHT. INCREASING MOISTURE DEPTH AND ISENTROPIC LIFT SHOULD PRODUCE SOME LIGHT RAIN LATE TONIGHT...AND THE QUESTION IS WHETHER TEMPS WILL BE COLD ENOUGH FOR FZRA. LOW TEMPS LOOK MARGINAL FOR THIS TO OCCUR...PLUS TEMPS MAY BE RISING BY THE TIME PRECIP BEGINS. NE TN MAY ALSO HAVE SOME WARMING HELP FROM DOWNSLOPE WINDS. WILL MENTION A SLIGHT CHANCE OF LIGHT FZRA NORTHEAST IN THE GRIDS BUT WITH VIRTUALLY NO ACCUMULATION. MOS GUIDANCE IS BULLISH ON POPS BUT EXPECT THAT QPF THROUGH SUNDAY MORNING WILL BE VERY LIGHT...JUST A FEW HUNDREDTHS. PLENTY OF LOW LEVEL MOISTURE REMAINS IN THE VALLEY THROUGH SUNDAY NIGHT...BUT MIDLEVEL MOISTURE IS LACKING AS WELL AS ANY FORCING MECHANISMS FOR LIFT. THE CATEGORICAL POPS OF THE NAM APPEAR WAY OVERDONE GIVEN THE LACK OF LIFT AND MOISTURE DEPTH. WILL LOWER POPS BACK TO THE CHANCE RANGE FOR SUNDAY NIGHT WITH PLENTY OF CLOUDS...CLOSER TO THE GFS. CONTINUED WARM ADVECTION AND A SLIGHT DOWNSLOPE WIND COMPONENT SHOULD BRING VALLEY TEMPS TO NEAR 50 OR THE LOWER 50S ON SUNDAY. LONG TERM (MONDAY THROUGH SATURDAY)...WEAK COLD FRONT TO MOVE JUST SOUTH OF THE FORECAST AREA EARLY MONDAY WITH PATCHY LIGHT RAIN ALONG AND BEHIND THE FRONT IN COLDER AIR MASS...MAINLY EARLY NORTH AND DURING THE DAY SOUTH. SKIES MAY BREAK OUT BY AFTERNOON NORTH. TEMPERATURES WILL START OUT WARMER BUT RISE ONLY INTO THE 40S TO LOWER 50S...STILL ABOUT 10 DEGREES BELOW NORMAL. THIS WILL HELP THE SNOW TO KEEP MELTING WITH ONLY HIGHER ELEVATIONS WITH MUCH LEFT. MONDAY EVENING SHOULD SEE A CONTINUED BREAK IN RAINFALL AS DRIER AIR FROM THE NORTH FILTERS IN BUT FRONT TO THE SOUTH WILL SURGE BACK NORTH AS A WARM FRONT LATE MONDAY NIGHT INTO EARLY TUESDAY. RAIN CHANCES INCREASE LATE WITH A LITTLE SNOW POSSIBLE LATE SW VIRGINIA MOUNTAINS BEFORE WARM FRONT OVERTAKES THE COLD AIR. A MUCH STRONGER SYSTEM DEVELOPS OVER THE CENTRAL AND SOUTHERN PLAINS TUESDAY WITH SOUTHERLY WINDS INCREASING LATER IN THE DAY IN THE TN VALLEY. TEMPERATURES WARM INTO THE 50S TO NEAR 60. THEN TUESDAY NIGHT AND WEDNESDAY RAINFALL INCREASES IN SHOWERS AND POSSIBLE THUNDERSTORMS AHEAD OF THE STRONG COLD FRONT. RIGHT NOW AMOUNTS LOOK TO BE AROUND ONE TO ONE AND ONE HALF INCHES FROM TUESDAY NIGHT INTO WEDNESDAY NIGHT. THIS MAY CAUSE LOCALIZED FLOODING DEPENDING ON HOW MUCH SNOW PACK IS LEFT. WEDNESDAY NIGHT AND THURSDAY MUCH COLDER WITH A CHANCE FOR WINTRY WEATHER MAINLY DURING THE DAY THURSDAY. WET SNOW AND OR SLEET IS A POSSIBILITY WITH TEMPERATURES STAYING IN THE 30S MOST OF THE DAY. LOWS THURSDAY NIGHT AS SKIES CLEAR WILL DROP INTO THE TEENS TO LOWER 20S. COLD HIGH PRESSURE MOVES IN FRIDAY AND THEN TEMPERATURES WARM SATURDAY SEVERAL DEGREES AS THE HIGH SHIFTS EAST.
-- End Changed Discussion --
&& .PRELIMINARY POINT TEMPS/POPS...
-- Changed Discussion --
CHATTANOOGA AIRPORT, TN 37 50 41 50 / 20 30 50 50 KNOXVILLE MCGHEE TYSON AIRPORT, TN 36 51 40 48 / 20 30 50 40 OAK RIDGE, TN 36 49 39 48 / 20 30 50 40 TRI CITIES AIRPORT, TN 30 52 39 48 / 20 40 50 50
-- End Changed Discussion --
&& .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$ DGS/TD

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