FXUS64 KMRX 200618 AFDMRX Area Forecast Discussion National Weather Service Morristown TN 218 AM EDT Fri Mar 20 2026 ...New DISCUSSION, AVIATION... .KEY MESSAGES... Updated at 201 AM EDT Fri Mar 20 2026 - Above normal temperatures this weekend. Highs Sunday will be 15 to 20 degrees above normal. - Scattered to isolated showers/storms Saturday with low-end potential of hail. && .DISCUSSION... Issued at 201 AM EDT Fri Mar 20 2026 Troughing off the Atlantic coast and a large ridge over the western Conus will maintain the NW flow pattern across the TN Valley region today. The warming trend will continue, with highs in the 70s central and south, to mid/upper 60s north. Winds could get breezy and gusty this afternoon as the SW wind gets channeled up the Valley, with winds at the top of the boundary layer between 25-30 kt. A surface front and a weak upper trough drop SW across the OH Valley on Friday night. This could bring some showers and isolated thunderstorms to our northern sections overnight. The front settles E-W along the TN/VA/KY border area on Saturday, and could be the focus for shower/thunderstorm development in the afternoon. Model soundings show some good midlevel lapse rates around 8-8.5 C/km and MLCAPE around 1200 J/kg at CHA, but there is a capping inversion that will need to be overcome to realize this instability. Forcing appears weak so confidence on a severe threat is low. Hail would be the main threat with gusty winds possible as well if storms can develop. A low pressure system over the Plains will keep a SW surface flow across our area on Sunday that will provide warm temperatures. Highs will reach well into the 80s for much of the TN Valley. A cold front will cross the area on Monday, but limited moisture will mean little in the way of precipitation. Cooler temperatures will follow for Tuesday and Wednesday, with highs in the 60s to lower 70s. && .AVIATION... (06Z TAFS) Issued at 201 AM EDT Fri Mar 20 2026 Calm under high pressure through sunrise. SW winds and gusts will increase for the day today. Clouds build in from the north later in the day. && .PRELIMINARY POINT TEMPS/POPS... Chattanooga Airport, TN 77 53 83 55 / 0 10 10 10 Knoxville McGhee Tyson Airport, TN 72 54 79 56 / 0 10 20 10 Oak Ridge, TN 72 52 79 53 / 0 10 20 10 Tri Cities Airport, TN 67 51 72 51 / 10 20 20 10 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$ DISCUSSION...DGS AVIATION...KS