Area Forecast Discussion
Issued by NWS Knoxville/Tri Cities, TN
Issued by NWS Knoxville/Tri Cities, TN
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012 FXUS64 KMRX 081752 AFDMRX Area Forecast Discussion National Weather Service Morristown TN 1252 PM EST Fri Nov 8 2024 ...New AVIATION... .UPDATE... Issued at 1050 AM EST Fri Nov 8 2024 A few sprinkles earlier this morning with moist airmass behind weak cold front that is now east of the Appalchians and across north Georgia. Patchy morning fog and lower clouds were lifting in the last few hours with some sunshine across parts of the east Tennessee Valley late this morning. The cooler airmass behind the front was just beginning to move into the northern plateau counties and extreme western Virginia counties adjacent to the Kentucky border. Clouds will gradually lift or dissipate today as higher pressure with the drier airmass moves in from the northwest. Ridging aloft will continue today over the southeast which should keep temperatures about 10 to 15 degrees above normal. Skies should be at least partly cloudy by mid afternoon. Temperatures late this morning ranged from mid to upper 50s near the northern and northwestern border close to Kentucky to 60s to around 70 elsewhere. High temperatures today will be cooler than Thursdays record highs with cloud cover and northerly wind flow. Could even see some early high temperatures west and north as drier, cooler air moves in. && .SHORT TERM... (Today and tonight) Issued at 215 AM EST Fri Nov 8 2024 Key Messages: 1. Some patchy fog is possible in the morning hours. 2. Skies clearing by this afternoon with a drier but still mild air mass building in. Discussion: A cold front is currently moving through the region. Winds have already shifted but the lower dew points are lagging behind, currently over Middle Tennessee and Central Kentucky. Patchy fog is possible this morning before the drier air moves in. Skies will be mostly sunny by this afternoon. Rain chances will be near zero as high pressure builds into the Ohio Valley. In the upper levels, ridging continues over the Southeast. I blended in NBM 10th percentile for dew points this afternoon with good mixing likely after the clouds clear out. Highs will be a bit cooler than yesterday in the lower to mid 70s in most locations with light northerly winds behind the cold front. && .LONG TERM... (Saturday through Thursday) Issued at 215 AM EST Fri Nov 8 2024 Key Messages: 1. Warm temperature remain in place through the middle of next week. 2. Best chances for widespread rain over the weekend into early next week. Discussion: Heading into Saturday we`ll still be sitting under the mid level ridge, but a slow moving front will be making it`s way across the Ohio and Tennesee Valleys and eventually move into the eastern Tennesee Valley over the weekend. Models are starting to hone in on the leading edge of the precipitation along the front moving onto the Cumberland Plateau late Saturday and into early Sunday. It will then slowly spread eastward throughout Sunday. Front struggles to keep it`s eastward momentum once it gets over the Appalachian mountains and if it gets hung up in our vicinity we could see an extra round of precipitation on Monday. But eventually the front gets a reinforcing shove from a fast moving shortwave zipping through the Ohio Vally early in the week. Probabilistic guidance has started to center around the storm total QPF amounts ranging from around 0.50" to 1.50" from Saturday through Monday. The highest amounts will likely be along the Cumberland Plateau and upslope side of the Appalachian Mountains... and the lower amounts in the eastern half of the TN valley. Assuming the QPF portion of the forecast verifies, this will likely be the most precipitation we`ve seen since Hurricane Helene impacted the area in late September. Obviously we`re not expecting nearly as much rain nor flooding impacts from this round of showers and storms. Behind the front the temperatures will dip a bit, but are still expected to remain above seasonal normals for the first half of the work week. It will however feel less humid as the drier air from the west/northwest funnels into the region behind the front. A more potent system is expected the second half of next week as a negatively tilted trough blasts through the region. This system looks to bring another (but shorter duration) round of showers to our area, and a much more dramatic cooldown on the backside of the system as we head towards the weekend. Temperatures look to finally dip below seasonal normals for Thursday/Friday after the trough/front swings through. && .AVIATION... (18Z TAFS) Issued at 1247 PM EST Fri Nov 8 2024 Ceilings are slowly rising from about 3000 feet early this afternoon and should stay VFR as northerly winds behind cold front bring drier and cooler air into the region. North winds will be lighter tonight with lower clouds likely moving back into CHA late tonight and Saturday morning before lifting late in the morning. && .PRELIMINARY POINT TEMPS/POPS... Chattanooga Airport, TN 58 75 58 65 / 0 20 30 50 Knoxville McGhee Tyson Airport, TN 52 74 57 67 / 0 10 40 60 Oak Ridge, TN 52 72 56 65 / 0 10 50 70 Tri Cities Airport, TN 45 73 51 65 / 0 0 30 60 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$ SHORT TERM...TD AVIATION...TD