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000 FXUS64 KMRX 150640 AFDMRX Area Forecast Discussion National Weather Service Morristown TN 240 AM EDT Tue Sep 15 2026...New DISCUSSION...KEY MESSAGES
Updated at 239 AM EDT Tue Sep 15 2026
- Above normal temperatures continue through this week.
- Most areas will remain dry this week, but the mountains will have some low chances of showers.
DISCUSSION
Issued at 239 AM EDT Tue Sep 15 2026
A large high pressure ridge will dominate the pattern across the Southeast this week. The main impact of the ridge will be abnormally warm temperatures continuing each day, with highs in the upper 80s to mid 90s in most of the TN Valley. CHA's streak of days reaching 90+ degrees (now at 42 days) will likely continue through the weekend. The "good" news is that with dewpoints mainly in the 65 to 70 range each day, the Heat Index will stay under Advisory criteria, but will still reach around 100 in the southern Valley.
Some isolated showers are possible in the mountains and SW NC today through Thursday. Rain chances may increase slightly later in the week as the ridge appears to weaken and shift west a bit, but showers will still be limited mainly in the higher terrain areas.
Rain chances are highly uncertain next week as some models are showing a tropical system moving into northern FL while a cold front approaches the OH Valley from the north. Confidence is low that these features will have run-to-run continuity this far out.
AVIATION
(06Z TAFS) Issued at 140 AM EDT Tue Sep 15 2026
Overall, quiet aviation conditions are expected with potential for fog at TRI again. Confidence is lower than last night, but a TEMPO was added in for the last few hours of the early morning. Otherwise, SCT clouds around 5,000 feet are expected through the day with southwesterly winds of around 10 kts.
PRELIMINARY POINT TEMPS/POPS
| Temperatures | Chance of Precipitation | |||||||
|---|---|---|---|---|---|---|---|---|
| Location | Tonight | Tomorrow | Tomorrow night | Next day | Tonight | Tomorrow | Tomorrow night | Next day |
| Chattanooga Airport, TN | 97 ℉ | 72 ℉ | 97 ℉ | 71 ℉ | 0% | 0% | 0% | 0% |
| Knoxville McGhee Tyson Airport, TN | 95 ℉ | 70 ℉ | 94 ℉ | 70 ℉ | 0% | 0% | 0% | 0% |
| Oak Ridge, TN | 94 ℉ | 70 ℉ | 93 ℉ | 69 ℉ | 0% | 0% | 0% | 0% |
| Tri Cities Airport, TN | 89 ℉ | 63 ℉ | 90 ℉ | 65 ℉ | 0% | 0% | 10% | 0% |
MRX WATCHES / WARNINGS / ADVISORIES
NC...NONE. TN...NONE. VA...NONE.
DISCUSSION...DGS AVIATION...BW