FXUS64 KMRX 210549 AFDMRX Area Forecast Discussion National Weather Service Morristown TN 149 AM EDT Sat Mar 21 2026 ...New AVIATION... .KEY MESSAGES... Updated at 140 AM EDT Sat Mar 21 2026 - Most of the area will remain dry for the rest of today and tonight, outside of low-end rain chances in southwest Virginia late. - Scattered showers and storms are possible late Saturday afternoon and evening. The main threat with these storms will be hail. - Warm and breezy conditions are expected Sunday with rain returning Sunday night into Monday morning. Then, dry and seasonally cooler conditions are expected until a warming trend late in the week. && .DISCUSSION... Issued at 234 PM EDT Fri Mar 20 2026 Currently, a strong upper high is centered over the desert southwest with shortwave troughing to our northeast. A frontal boundary is also near the Great Lakes. This has put the region in a northwesterly flow pattern aloft with southwesterly flow in the lower levels. Isolated showers and storms will track in southwest Virginia late tonight into Saturday morning, largely keeping the region dry. On Saturday, a very weak shortwave will move overhead with the northern front moving southward. This will lead to increasing lift and moisture, sufficient for convection late afternoon into the evening. Winds aloft will be only around 20 to 25 kts with largely elevated instability of 500 to 1,000 J/kg and mid- level lapse rates over 6 C/km. This will lead to potential for hail within any storms, especially with WBZ heights below 10,000 feet. CAMs differ significantly on how much convection develops, if any. By Sunday, the flow aloft will become more zonal as troughing lifts to the northeast, followed by another deepening trough to the northwest. A surface low will then track towards the northeast, increasing low-level winds and pulling the front further south. This will lead to very warm and breezy conditions on Sunday but with rain chances not arriving until late in the night or early Monday morning. While winds will be stronger, instability is indicated to be nearly 0, keeping chances for actual convection limited. Still, the stronger MSLP gradient and synoptic flow could lead to gusty winds. During the day on Monday, the front will have moved south of the region with high pressure expanding from the north. This will promote drier and seasonally cooler conditions, which remain generally the same into Tuesday. By Wednesday, broad ridging will expand from the southwest with high pressure shifting eastward, leading to a return of southerly flow and increasing moisture and WAA. Low-end rain chances are indicated for Wednesday as the remnant front is pulled back northward, but this is limited overall. Late in the week, a stronger system is expected to develop and track far to our north. Overall, the impacts for our area look limited, but the question will be when and if its associated front arrives. This could bring showers and storms but likely not until later Thursday or Friday. && .AVIATION... (06Z TAFS) Issued at 140 AM EDT Sat Mar 21 2026 VFR can generally be expected outside of any precipitation. CHA likely to stay dry. LLWS kept at TRI during the overnight hours. Possible leftover precipitation from the north will reach TRI later this morning. PROB added at TYS for the later afternoon and evening with possible development of storms later tonight. The near-storm environment doesn't appear that damaging winds will be much of a threat, mainly hail. && .PRELIMINARY POINT TEMPS/POPS... Chattanooga Airport, TN 83 58 86 61 / 30 20 0 0 Knoxville McGhee Tyson Airport, TN 79 58 84 59 / 30 20 0 10 Oak Ridge, TN 80 56 84 58 / 30 20 0 20 Tri Cities Airport, TN73 53 80 55 / 20 10 0 30 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$ DISCUSSION...BW AVIATION...KS