Area Forecast Discussion
Issued by NWS Knoxville/Tri Cities, TN
Issued by NWS Knoxville/Tri Cities, TN
588 FXUS64 KMRX 061104 AAA AFDMRX Area Forecast Discussion...UPDATED National Weather Service Morristown TN 704 AM EDT Sun Jul 6 2025 ...New AVIATION... .SHORT TERM AND LONG TERM... (Today through Saturday) Issued at 132 AM EDT Sun Jul 6 2025 Key Messages: 1. Hot and mostly dry again today. 2. Monday into Tuesday we transition from a dry pattern, to one increasingly more conducive for afternoon shower and thunderstorm activity that lasts through the forecast period. Discussion: The entirety of the forecast can be boiled down to a battle between troughing over the Great Lakes and Ohio valley, and the subtropical ridge attempting to build back this direction from the Gulf. It appears the troughing will win out, with rain chances increasing through the week as a result and temperatures hanging right around normal for this time of year. Tropical Storm Chantal will move north from the South Carolina coast this morning to central Virginia by this evening, ahead of a shortwave moving into the Ohio valley. Locally we should remain dry most everywhere but an isolated shower or two could occur in the higher terrain. Afternoon highs will run a couple of degrees above normal once again today. Monday onward the aforementioned troughing will exert increasing influence over the weather in the southern Appalachians, primarily through weakening the ridge aloft and allowing for more afternoon shower and thunderstorm activity. Monday should be a transition day, with more activity over the higher terrain and some increasing chances for storms to move into the valley by late afternoon or early evening. For Tuesday onward, troughing to our north becomes more pronounced, and expect a general increase in rain chances across the board along with near normal temperatures. The only caveat here is that NBM guidance is very aggressive with rain chances, showing likely to even categorical PoPs into the lower elevations by week`s end. Pattern wise, there`s support for this as the troughing over the Great Lakes and Ohio valley region lays out a stationary boundary to our north and also draws moisture northward from the Gulf into the southern Appalachian region. While this pattern will favor increased convective coverage, I`m not sure such high PoPs in the NBM are warranted for lower elevations. I toned down the rain chances in the TN valley Mon and Tue, but let the NBM ride thereafter. Time will tell if additional adjustments are needed in the lower elevations for mid to late week. && .AVIATION... (12Z TAFS) Issued at 702 AM EDT Sun Jul 6 2025 VFR conditions will prevail through the period. Some ISOLD SHRA/TSRA may develop over the Appalachians or over the Cumberland Plateau today but coverage will be sparse and won`t affect any terminals. Winds will be light and variable. && .PRELIMINARY POINT TEMPS/POPS... Chattanooga Airport, TN 95 73 96 74 / 10 10 20 10 Knoxville McGhee Tyson Airport, TN 93 72 93 72 / 10 10 20 10 Oak Ridge, TN 93 71 93 71 / 10 10 30 10 Tri Cities Airport, TN 89 67 90 69 / 10 10 20 20 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$ SHORT TERM...CD LONG TERM....CD AVIATION...CD