Area Forecast Discussion
Issued by NWS Knoxville/Tri Cities, TN
Issued by NWS Knoxville/Tri Cities, TN
352 FXUS64 KMRX 050627 AFDMRX Area Forecast Discussion National Weather Service Morristown TN 227 AM EDT Sat Jul 5 2025 ...New SHORT TERM, LONG TERM, AVIATION... .SHORT TERM... (Today and tonight) Issued at 135 AM EDT Sat Jul 5 2025 Key Messages: 1. Dry and seasonably warm. Discussion: High pressure remains in control of the weather across the southern Appalachian region today and tonight. Despite a weak tropical system off the South Carolina coast moving northward into the Carolinas by tonight, and a shortwave moving through the upper midwest, upper heights remain steady over our CWA today. As such, today will still be seasonably warm, with temperatures in the low to mid 90s or slightly above normal. Not expecting much, if any, shower activity today as models show a notable capping inversion aloft so convection will likely be suppressed. You can never rule out an isolated storm over the higher terrain here in the summer, but it seems unlikely today. && .LONG TERM... (Sunday through Friday) Issued at 135 AM EDT Sat Jul 5 2025 Key Messages: 1. Steady increase in afternoon rain chances through the period, returning first to the mountains on Sun, with afternoon rain chances area wide by Tue/Wed. 2. Increasing humidity with heat index values approaching 100 in the southern Valley Monday through Wednesday. Discussion: There`s been no significant change in the forecast from yesterday`s day shift. As such, with minimal edits the previous discussion follows. The ridge starts to loosen its grip a bit on Sunday as it gets pinched between a tropical low moving northward from the SC coast into central North Carolina, and a shortwave trough moving into the Great Lakes from the west. Forecast soundings on Sunday don`t appear as capped compared to Saturday, and low level moisture increases slightly. This should allow for a little better chance of afternoon showers and storms developing in the mountains. Monday looks similar, but with dewpoints possibly pushing into the 70s during the afternoon, the slight chance PoP spreads into the Valley. Heat Index values may start pushing toward 100 in the southern Valley as well. A front pushes across the OH Valley and toward our area late Monday as a broad troughing pattern sets up next week across the eastern Conus. This will allow for a greater chance of afternoon by midweek as the front gets closer to our area from the north. Doesn`t look like we get an actual frontal passage, but with an eastern troughing pattern in place, the Atlantic ridge shifting westward, and the front nearby to our north, we could be setting up for a wetter pattern from Wednesday onward. && .AVIATION... (06Z TAFS) Issued at 135 AM EDT Sat Jul 5 2025 Some haze, likely from an increase in particulates from area fireworks, will continue at KCHA through daybreak before improvement is seen in VSBY there. The next several hours at KCHA notwithstanding, VFR conditions should prevail at all sites through the period with just some FEW-SCT050 bases associated with afternoon CU field. && .PRELIMINARY POINT TEMPS/POPS... Chattanooga Airport, TN 94 72 95 73 / 0 0 10 0 Knoxville McGhee Tyson Airport, TN 94 70 93 72 / 0 0 10 10 Oak Ridge, TN 94 69 93 71 / 0 0 10 0 Tri Cities Airport, TN 89 64 90 67 / 10 0 10 10 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$ SHORT TERM...CD LONG TERM....CD AVIATION...CD