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 180735 AFDMRX Area Forecast Discussion National Weather Service Morristown TN 335 AM EDT Tue Jul 18 2017 .SHORT TERM...
-- Changed Discussion --
(Today and tonight)... Weather pattern very similar to Mondays except dew points expected to be a little higher today which will bring Heat Index temperatures into the lower 90s northeast and central east Tennessee and mid to even upper 90s southern valley for a couple hours late this afternoon. No fog has formed as of 300 AM EDT and expect only isolated patches between now and sunrise. Weak upper trough along the east coast and Appalachians will keep temperatures in the eastern mountains slightly cooler with clouds forming in the afternoon and scattered late day showers and thunderstorms there. Upper ridging from the Plateau westward will keep afternoon storms at a minimum there so took rain chances out except extreme south and dry conditions as well for the lower elevations of the Tennessee Valley. Storms should end early in the mountains with skies mostly clear overnight. Lows about average for mid summer mid 60s to lower 70s. .LONG TERM...(Wednesday through Monday)... Main concern through the rest of the week will be intensifying heat wave across the area with heat indices increasing to 100-105 degrees over most of the Tennessee Valley for Friday and Saturday. Heat Advisories may be needed across the southern half of the Tennessee Valley. An upper and surface ridge will be the main player across the region through Friday. Mid-level warm air will limit convection with a capping inversion. Isolated storms can not be ruled out, but coverage will be limited. Increasing low-level moisture by Friday into the weekend with heat indices becoming a problem. For this weekend and Monday, upper ridging slowly weakens as trough over the Carolinas/southeast United States retrogrades south/then west. The mid-level warm layer will move out of the area with increasing moisture (PWs increasing to 1.7-1.9 inches). Increasing moisture and instability will allow convection to increase in coverage and intensity. Isolated strong/severe storms are possible each afternoon/evening. Main concern being damaging winds, heavy rainfall, and frequent lightning.
-- End Changed Discussion --
&& .PRELIMINARY POINT TEMPS/POPS...
-- Changed Discussion --
Chattanooga Airport, TN 92 72 93 73 / 10 10 20 10 Knoxville McGhee Tyson Airport, TN 91 68 91 71 / 10 10 20 10 Oak Ridge, TN 92 68 92 71 / 10 10 20 10 Tri Cities Airport, TN 90 65 89 67 / 10 10 10 10
-- End Changed Discussion --
&& .MRX WATCHES/WARNINGS/ADVISORIES... NC...None. TN...None. VA...None. && $$ TD/DH

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