Area Forecast Discussion
Issued by NWS Nashville, TN
Issued by NWS Nashville, TN
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659 FXUS64 KOHX 080156 AFDOHX Area Forecast Discussion National Weather Service Nashville TN 856 PM CDT Tue May 7 2024 ...New UPDATE... .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... (00Z TAFS) Issued at 617 PM CDT Tue May 7 2024 A very active TAF period is expected with several rounds of thunderstorms. For the remainder of this evening, storms will continue to be very hit-and-miss. But tonight, likely after 06Z, a more organized line of storms is expected to move across the area. Additional isolated to scattered storms are expected after 12Z with more widespread activity developing late Wednesday afternoon and evening. Any thunderstorm will be capable of producing gusty winds, hail, and frequent lightning along with low cigs. && .PRELIMINARY POINT TEMPS/POPS... Nashville 69 84 68 85 / 80 80 100 40 Clarksville 68 82 66 82 / 60 80 100 20 Crossville 64 78 62 78 / 80 80 90 80 Columbia 68 85 66 84 / 70 80 100 50 Cookeville 66 80 65 79 / 80 80 100 70 Jamestown 64 80 63 78 / 80 80 90 80 Lawrenceburg 69 84 66 84 / 70 70 100 50 Murfreesboro 67 83 66 84 / 80 80 100 50 Waverly 66 82 65 82 / 70 70 100 20 && .OHX WATCHES/WARNINGS/ADVISORIES... Flood Watch from 1 AM CDT Wednesday 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.....Clements