Area Forecast Discussion
Issued by NWS Nashville, TN
Issued by NWS Nashville, TN
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555 FXUS64 KOHX 260202 AFDOHX Area Forecast Discussion National Weather Service Nashville TN 902 PM CDT Wed Sep 25 2024 ...New UPDATE... .UPDATE... Issued at 847 PM CDT Wed Sep 25 2024 A few showers continue along the plateau where the cold front stalled out. To our northwest, the upper low is spinning in place near PAH with a few showers north of our area. The shower activity may temporarily decrease after midnight before coverage begins to pick up again in the morning along the plateau. The first slug of tropical moisture from Helene will overspread the area Thursday afternoon and evening. There are no major changes to the models since this afternoon and no changes to the forecast at this point. && .SHORT TERM... (Today through Tonight) Issued at 107 AM CDT Wed Sep 25 2024 A cold front has pushed eastward through Middle TN with latest obs showing it just east of the Plateau. This front is expected to stall in this area today as an upper-level low digs into northern AR. In the wake of this front, temperatures will be cooler with forecast highs in the 70s to near 80. While PWATs have trended down over the past 24 hours, there is still plenty of moisture across the area with PWATs over an inch. This will lead to an additional round of showers and thunderstorms that develops this morning and lingers through tonight. With the position of the front, best coverage will favor the east today. In the wake of the cold front and with cloudy skies, instability will be less with CAPE values forecast to be less than 1000 J/kg. With less instability and less forcing, strong to severe thunderstorms are not expected today. Cloud cover partially clears tonight, allowing for patchy fog to develop. && .LONG TERM... (Thursday through next Wednesday) Issued at 107 AM CDT Wed Sep 25 2024 Confidence continues to increase for soaking rainfall starting Thursday and continuing into the weekend. The aforementioned upper-level low that digs into northern AR today will stall and linger in this area into the weekend. Meanwhile, all eyes continue to be on the tropics with now Tropical Storm Helene. Helene is expected to strengthen into a major hurricane before making landfall along the Florida Panhandle late Thursday. Before Helene`s landfall, tropical moisture will be pulled northward with the help of that low over AR. The heaviest rainfall expected from Helene will likely get started Thursday night and continue into Friday as its remnants then track into eastern TN. What`s left of Helene at this point gets pulled northwestward across Middle TN/KY and is absorbed into the AR upper-level low. This low then finally ejects towards the northeast this weekend. Heaviest rainfall during this event is expected Thursday night and into Friday. A general 2 to 3 inches of rain is expected over this time frame, but higher amounts of 4 to 5 inches will favor areas across the Plateau. This is all highly dependent on the track of Helene, and a jog towards the east will result in lower rain amounts. Minor flooding is still possible with all this rain, but with the current drought status, river levels are low enough that there is room for this welcome rain. Winds will also be gusty, especially on Friday as the remnants move through with gusts of 30 to 35 mph currently forecast. Scattered showers and thunderstorms will linger through the weekend before the low finally moves out of our area. Drier weather looks to be favored early next week with temperatures feeling fall-like as we head into the first week of October. && .AVIATION... (00Z TAFS) Issued at 624 PM CDT Wed Sep 25 2024 VFR conditions are expected at BNA/MQY/CKV this TAF period with DZ this evening and -SHRA by late Thursday afternoon. For CSV/SRB, VFR cigs early in the TAF period will become MVFR/IFR by tonight/tomorrow due to VCSH/-SHRA ahead of Hurricane Helene. Tempo LIFR at CSV is also anticipated towards sunrise. Light north to northeast winds overnight at all airports will increase to 6-12 knots on Thursday. && .PRELIMINARY POINT TEMPS/POPS... Nashville 62 79 67 76 / 10 60 90 100 Clarksville 58 79 65 74 / 10 50 90 100 Crossville 57 69 60 70 / 50 80 90 100 Columbia 58 79 63 72 / 10 50 90 100 Cookeville 59 72 63 71 / 40 80 90 100 Jamestown 58 70 62 71 / 50 80 90 100 Lawrenceburg 58 78 63 72 / 20 50 90 100 Murfreesboro 60 79 65 74 / 20 70 90 100 Waverly 57 79 63 72 / 10 50 90 100 && .OHX WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE.......Reagan SHORT TERM...Clements LONG TERM....Clements AVIATION.....Shamburger