Area Forecast Discussion
Issued by NWS Knoxville/Tri Cities, TN
Issued by NWS Knoxville/Tri Cities, TN
608 FXUS64 KMRX 011708 AFDMRX Area Forecast Discussion National Weather Service Morristown TN 108 PM EDT Thu Oct 1 2026 ...New AVIATION... .KEY MESSAGES... Updated at 106 PM EDT Thu Oct 1 2026 - Dry and abnormally warm conditions are expected today with highs well into the 80s to low 90s in the south. - Chances for showers and isolated storms will increase tomorrow and through the weekend with locally heavy rainfall possible. - Drier and cooler conditions will return next week. && .DISCUSSION... Issued at 1240 AM EDT Thu Oct 1 2026 Upper level ridging currently pinches up the SE CONUS with surface high pressure centered just off of the Mid- Atlantic. One last day of area-wide dry weather and abnormally hot temperatures today, as a closed low within the pattern eventually phases with the trough with its eastward progression. A frontal system currently stretching north into the TX and OK panhandles, will be knocking on our doorstep as we welcome the first weekend of October. With the surface high pressure situated to the east, southerly flow will bring a marked return of higher dew points this afternoon compared to yesterday. Moisture surrounds the area during the early morning hours tomorrow to our west and south. The frontal system is forecast to enter the Mississippi Valley around that time. Although tomorrow starts out dry, precipitation chances increase the further we get into the day. The frontal system does cross the area sometime late tomorrow into early Saturday, however, it will become stationary just to our south and not totally clear the area until possibly later Sunday. What this means will be periods of wet weather for the entire area this weekend. So far, a marginal risk for flash flooding is in place. With the highest FFG across our southern areas, some places could have the capacity to absorb a lot of the rainfall not bringing much of a threat unless training occurs with consecutive heavy showers/storms. Right now, Sunday has the heaviest rainfall accumulation as the low center moves overhead as it begins to push out. Forecast PWATs at this time do show values nearing or going just above 2 inches which would be conducive for heavy rain makers. As far as any storms, there isn`t a severe threat, but there could be embedded storms. Instability overall will be lacking. The greatest threat this weekend will be heavy rain with the possibility of localized flash flooding. Grand total QPF amounts, though being fine tuned with each forecast, show the entire forecast area seeing at least one inch of rain. Some areas could see over two, possibly up to 3 inches when everything is said and done. Due to overall uncertainty of amounts still, high FFG, etc. have elected to continue with low probability of hazardous weather for Friday onward. Rain clears the region as we enter a new work week next week. A secondary front will send everything out of here replacing it with dry weather, northerly flow, and temperatures typically recorded in early October. Surface high pressure sinks in from the north and frontal systems until the end of the period are forecast to remain well to our south and to the north, for now. && .AVIATION... (18Z TAFS) Issued at 106 PM EDT Thu Oct 1 2026 Main concern is potential of fog development at TRI. Any steam fog may move into the terminal early Friday morning. Confidence is too low to include. Otherwise, VFR conditions with surface and upper ridging keeping things quiet. && .PRELIMINARY POINT TEMPS/POPS... Chattanooga Airport, TN 68 92 69 86 / 0 40 40 70 Knoxville McGhee Tyson Airport, TN 65 89 67 82 / 0 40 60 70 Oak Ridge, TN 64 88 66 80 / 0 50 60 70 Tri Cities Airport, TN 59 85 63 76 / 0 30 40 80 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$ DISCUSSION...99 AVIATION...DH