Area Forecast Discussion
Issued by NWS Nashville, TN
Issued by NWS Nashville, TN
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364 FXUS64 KOHX 080531 AFDOHX Area Forecast Discussion National Weather Service Nashville TN 1231 AM CDT Wed May 8 2024 ...New AVIATION... .UPDATE... Issued at 855 PM CDT Tue May 7 2024 It`s been a quiet evening across the area but that should start to change over the next several hours. A short wave trough is moving over the Great Lakes with a cold front stretching to our west. Storms have started to develop along this cold front over southern IL and we should continue to see storms develop along this front over IL south into KY. The latest models are pushing back timing for us a bit but we should start to see a few storms develop over TN after 10 PM. The front will then start to push in from the north after midnight and that will bring the best chance for widespread convection. Storms will continue to push south overnight to around daybreak. Meso Analysis shows a ton of CAPE over our area with MLCAPE above 2000 j/kg and bulk shear above 40 knots. This is plenty to see some more organized storms. Winds and large hail are going to be the main threat with storms. Still can`t rule out a tornado or two as we will see low level veering in the winds and 0-1 km shear above 20 knots, but things do look to get capped off by midnight or so which should limit the tornado threat. PWAT values are between 1.40-1.50" across the area and heavy rain can be expected with any thunderstorms. The cold front will stall over our area tomorrow morning and start to lift north as a warm front. As the front transition to a warm front we could get training storms along this boundary and flash flooding would be a major concern if we see that set up. There is some uncertainty on where we see that front set up and how slow it will be to push north of our area. It will likely push north of our area by the early afternoon and that will likely give us a brief break in widespread convection and heavy rain before the next round moves in. More severe weather is likely tomorrow and you should remain weather aware and up to date with the latest forecast. && .SHORT TERM... (Rest of today through Thursday night) Issued at 1141 AM CDT Tue May 7 2024 Earlier this morning, a weakening area of showers and thunderstorms was clipping our far northwest. This activity remained sub severe. And now it`s warm and muggy once again with current temperatures in the lower to mid 70s. High temperatures are expected to reach the mid 80s so we will become more unstable as we reach into the afternoon hours. Dynamics are still quite weak and afternoon convective coverage will be limited. However, storms that fire could still reach severe limits as capes increase into the 2000-2500 j/kg range. A weakening front will be on approach tonight. This will lead to a line of convection which will push toward our northwestern counties around 9 pm or so. Still plenty of instability will be in place along with some shear as well. The activity will work across the area and reach our southern counties toward sunrise. Again, all severe types will be in play but the better chances appear to be across our northern half where the slight risk resides. On Wednesday, what appears to be a warm front will be lifting northward in the morning. This will bring us yet another potential threat of severe weather through about midday. In the afternoon, the warm front will shift the better focus of severe to our north across KY. This may hold through the afternoon but will only serve to allow us to warm up and destabilize even more. Wednesday night looks like the biggest of all the severe weather rounds. The primary catalyst will be a cold front with the fropa expected late Wednesday night or Thursday morning. Prior to the fropa, it looks as though convection will fire in the prefrontal area as well as along and just ahead of the boundary. Excellent phasing of forcing, instability and shear looks likely. Mid level lapse rates support large hail so all types of severe are on the table. Timing looks like from 6 pm through 3 am, so a long night looks to be in store. Helicities are in the 150-300 range but the classic type of synoptic spring storm setup is not quite there. The upper pattern is zonal with some w-e elongation noted with the surface low. However, with the aforementioned strong phasing, the tornadic threat is still appreciable. Otherwise, flooding could also be concern, depending largely on how much rain occurs during the Wednesday morning/early afternoon earlier round. Near term temps continue to look warm through Thursday with 60s for lows and mostly lower 80s for highs. We will cool down some by Friday morning, behind the front, with upper 40s and lower 50s for lows. && .LONG TERM... (Friday through next Tuesday) Issued at 1141 AM CDT Tue May 7 2024 In the extended forecast, there will still be a few shower chances into the weekend along with cooler temperatures. This will be followed by warmer temps for early next week as some ridging returns. The cooler temps over the weekend will feature lows upper 40s to lower 50s, warming back up to around 60 degrees next week. Highs will be in the 70s for the weekend, and then lower 80s next week. && .AVIATION... (06Z TAFS) Issued at 1231 AM CDT Wed May 8 2024 Complex and uncertain forecast over the next 24 hours. Do expect most to remain VFR for the next few hours, with CSV/SRB being outliers and currently having MVFR cigs. A line of TSRA will move closer to the area after 09Z, but there is a lot of uncertainty with coverage and intensity from then through most of tomorrow. Coverage will likely be scattered, but if TSRA moves directly over a terminal could experience VIS/CIG impacts and gustier winds than currently in the TAF. Another round and increased confidence in TSRA near the end of the current TAF period. Winds will remain generally from the south throughout the TAF period. && .PRELIMINARY POINT TEMPS/POPS... Nashville 84 69 84 58 / 90 80 50 10 Clarksville 82 68 82 54 / 80 90 30 10 Crossville 79 63 78 53 / 80 80 70 20 Columbia 85 66 85 55 / 80 90 60 20 Cookeville 80 65 80 54 / 90 90 70 20 Jamestown 80 63 78 53 / 90 90 70 20 Lawrenceburg 84 66 84 56 / 70 80 70 20 Murfreesboro 85 66 84 55 / 70 90 50 20 Waverly 82 65 83 54 / 80 80 30 10 && .OHX WATCHES/WARNINGS/ADVISORIES... Flood Watch through Thursday morning for Bedford-Cannon-Cheatham- Clay-Coffee-Cumberland-Davidson-De Kalb-Dickson-Fentress-Giles- Grundy-Hickman-Houston-Humphreys-Jackson-Lawrence-Lewis-Macon- Marshall-Maury-Montgomery-Overton-Perry-Pickett-Putnam-Robertson- Rutherford-Smith-Stewart-Sumner-Trousdale-Van Buren-Warren-Wayne- White-Williamson-Wilson. && $$ UPDATE.......Mueller SHORT TERM...21 LONG TERM....21 AVIATION.....Adcock