683 FXUS64 KMRX 282326 AFDMRX AREA FORECAST DISCUSSION National Weather Service Morristown TN 726 PM EDT Tue Sep 28 2021 .UPDATE... FOR 00Z AVIATION. && .SHORT TERM...(Tonight and Wednesday)... Key Messages: 1. Mostly clear tonight but fog development expected again especially near rivers/lakes and it may be locally dense. 2. Wednesday will feature plenty of sunshine with high temperatures a few degrees above normal. Discussion: Short wave energy diving southeastward out of the Great Lakes will sharpen the East Coast upper level long wave trough, while the narrow upper ridge centered to our west shifts slowly east. A weakening and moisture starved cold front will sag south toward our area and may make it into our northern areas late tonight or Tuesday morning but this front will have little impact on our weather overall. Will see a mostly clear sky overnight with fog development expected once again mainly near rivers/lakes, and it may be locally dense. Once any morning fog dissipates, Wednesday will have plenty of sunshine and temperatures similar to today, with highs ranging from 80 to 85 in most valley locations. LW .LONG TERM...(Wednesday night through Tuesday)... Key Messages: 1. Dry weather and near normal temperatures expected through the rest of the work week. 2. An increasing chance for showers over the weekend into next week. Discussion: Quiet weather will continue for the rest of the work week as we sit between two troughs on the western and eastern coasts of the U.S. Temperatures are expected to remain fairly consistent as we head into the weekend, a few degrees above normal with most locations reaching into the 80's in the afternoons. High pressure will begin to weaken as we head into the weekend with another weather system expected to bring rain to the area. As high pressure near the surface begins to move off to the east with an approaching trough from the Rockies, southerly winds near the surface will begin to bring in Gulf moisture to the region. A couple of shortwaves will move out ahead of the main trough and currently look like they'll slide up through the Ohio Valley early in the weekend. This could possibly bring showers and thunderstorms to the Tennessee Valley and southern Appalachians, but most models think that the best forcing mechanisms will remain to our west and north. Better chances for precipitation will likely come late in the weekend or early next week as the main brunt of the trough/low begins to move into the eastern half of the U.S. Recent runs of the GFS have slowed down a bit with the timing of the main system and is now more in line with the ECMWF and it's ensembles. In response have decreased PoPs at the beginning of the weekend and increased them on Sunday into early next week. Other weather of note will be the cool down with this weekend/early week system as temperatures are expected to drop 5-10 degrees through early next week with daytime highs only reaching into the 70's starting on Monday. ABM && .AVIATION... 00Z TAF DISCUSSION. Conditions tonight and into the morning hours will be similar to what has been seen recently. BR is likely to form again in river valleys with the greatest potential for aviation impacts at TRI. Otherwise, VFR conditions will prevail again through the day tomorrow. BW && .PRELIMINARY POINT TEMPS/POPS... Chattanooga Airport, TN 61 85 63 85 63 / 0 0 0 10 0 Knoxville McGhee Tyson Airport, TN 59 83 61 85 60 / 0 0 0 0 0 Oak Ridge, TN 58 84 61 84 60 / 0 0 0 0 0 Tri Cities Airport, TN 56 82 55 83 53 / 0 0 0 0 0 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$