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

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
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 121847 AFDMRX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MORRISTOWN TN 247 PM EDT SAT JUL 12 2014 .SHORT TERM (TONIGHT THROUGH MONDAY NIGHT)...CURRENT SURFACE ANALYSIS SHOWS A WEAK AREA OF HIGH PRESSURE CENTERED OVER THE SOUTHERN APPALACHIANS...WITH A WARM AND HUMID AIR MASS OVER THE FORECAST AREA. AREA RADARS REVEAL SOME ISOLATED CONVECTION DEVELOPING AROUND THE APPALACHIAN MOUNTAINS AND CUMBERLAND PLATEAU THIS AFTERNOON...WHICH SHOULD GRADUALLY DIMINISH AFTER THE SUN SETS. CONVECTION IS EXPECTED TO DEVELOP AGAIN BY SUNDAY AFTERNOON...BUT WITH INSTABILITY PROGGED TO INCREASE A LITTLE MORE ON SUNDAY...THINK THAT THE CONVECTIVE COVERAGE WILL BE A LITTLE BETTER OVER THE ENTIRE FORECAST AREA. AN UNSEASONABLY STRONG UPPER-LEVEL TROUGH IS THEN PROGGED TO AMPLIFY OVER THE EASTERN HALF THE NATION BY SUNDAY NIGHT...WHICH WILL PUSH A COLD FRONT TOWARDS THE FORECAST AREA ON MONDAY. MODELS INDICATE THAT A VERY UNSTABLE AIR MASS COULD DEVELOP OVER THE FORECAST AREA BY MONDAY AFTERNOON AND EVENING...ALONG WITH FAIRLY STRONG (FOR THIS TIME OF YEAR) UPPER- LEVEL WINDS. THUS...IT APPEARS THAT AN FAIRLY EXTENSIVE LINE OF STRONG TO SEVERE TSTORMS WILL DEVELOP OVER THE OHIO RIVER VALLEY SUNDAY NIGHT...AND WILL THEN EVENTUALLY BRING DAMAGING WINDS...LARGE HAIL...AND LOCALLY HEAVY RAINFALL ACROSS THE FORECAST AREA BY MONDAY AFTERNOON AND EVENING. AS FOR TEMPS...GFS AND NAM GUIDANCE NUMBERS ARE IN GENERAL AGREEMENT THROUGH MONDAY NIGHT...AND WILL COMPROMISE BETWEEN THE TWO WHERE SOME SLIGHT DIFFERENCES ARE NOTED. .LONG TERM (TUESDAY THROUGH SATURDAY)...A STRONG COLD FRONT WILL MOVE ACROSS THE AREA ON TUESDAY. HOWEVER...BEFORE IT PULLS THROUGH LATE IN THE DAY...WILL CONTINUE TO SEE SCATTERED CONVECTION ACROSS THE SOUTHERN APPALACHIAN REGION ESPECIALLY DURING THE MORNING HOURS. BEHIND THE FRONT...SEASONALLY COOL AND DRY AIR WILL MOVE IN. ONLY CONCERN WILL BE THE EXITING FRONT. IT IS EXPECTED TO PUSH THROUGH THE MRX CWA AND STALL TO OUR SOUTH EARLY IN THE EXTENDED. A SERIES OF WEAK DISTURBANCES WILL MOVE ALONG IT...TRACKING JUST TO OUR SOUTH AND EAST. SCATTERED CONVECTION ASSOCIATED WITH THIS FEATURE MAY MOVE INTO THE AREA...ESPECIALLY NEAR THE TN/GA BORDER AND ALONG THE SOUTHERN APPALACHIANS. && .PRELIMINARY POINT TEMPS/POPS... CHATTANOOGA AIRPORT, TN 72 93 72 91 / 10 20 20 60 KNOXVILLE MCGHEE TYSON AIRPORT, TN 70 92 70 90 / 10 20 30 60 OAK RIDGE, TN 70 92 70 90 / 10 20 30 60 TRI CITIES AIRPORT, TN 65 90 65 88 / 10 20 40 60 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$ DMG/MJB

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