Area Forecast Discussion
Issued by NWS Nashville, TN
Issued by NWS Nashville, TN
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604 FXUS64 KOHX 140545 AFDOHX Area Forecast Discussion National Weather Service Nashville TN 1245 AM CDT Tue May 14 2024 ...New AVIATION... .UPDATE... Issued at 829 PM CDT Mon May 13 2024 Nice and quiet at update time this evening. Light sprinkly rain has moved out of here and into KY and these quiet conditions are expected for the next several hours. However, before sunrise, CAMs continue to develop showers and thunderstorms in our west, traversing the mid-state through the mid-morning hours. These should be garden-variety storms, but will likely produce brief heavy rain and some decent rumbles of thunder. CAMs also want to develop a second round of storms for the afternoon/evening hours tomorrow. If you didn`t see, SPC spread a Marginal Risk over the entire mid-state tomorrow, and from the looks of it, for good reason. I don`t expect anything widespread in the severe category, but after pouring over forecast soundings, they are proving to be interesting. Lapse rates approaching 7.0 deg/km, CAPE values in the 1200-1500 J/Kg range and several algorithm parameters suggesting the potential for a couple strong to severe wind gusts tomorrow. However, there are a couple of limiting factors, from what I`m seeing. Shear is lacking. Not greatly lacking, but 20 kts of deep layer shear is barely enough to get thunderstorms going, let alone sustain updrafts. We`ll see how the shear pans out, but I would remain weather aware tomorrow, especially if you have outdoor plans. Like I said, it shouldn`t be anything widespread, but I would not be surprised for the need for a couple severe warnings for wind tomorrow afternoon. && .SHORT TERM... (Rest of today through Tuesday) Issued at 1122 AM CDT Mon May 13 2024 It`s pretty cool out there this morning with temps in the low to mid 60s. Current radar imagery shows some very light and scattered precip across the area. I would be surprised if any of it was making it to the ground, though, as this morning`s balloon launch shows a large dry layer above us. As the upper-level low continues to scoot in, moisture will fill in and rain will likely start making it to the ground this afternoon. The scattered activity will continue through the afternoon. Instability should stay on the low side, but can`t rule out a few rumbles of thunder today. For tonight, the latest CAMs are showing a line of thunderstorms developing across west Tennessee overnight tonight around 3 to 4 am and pushing east through the area during the morning hours Tuesday. While there won`t be much instability around during that time, there could still be some thunder. Models show a second line developing between 12pm-2pm Tuesday afternoon that could bring a marginal severe threat, particularly to areas south of I-40. Right now, the main threats with that line appear to be small hail and damaging winds. I know with the recent bout of severe weather, that`s not what people want to hear. On the plus side, Tuesday looks like the only day (for now at least) of any consequence...And the threat is marginal. 0-6km shear values will be pretty low, lapse rates aren`t great (around 6 C/Km), and mean instability is around 1400 J/KG. Something else worth noting is that there could be a few heavy downpours with PWAT values near 1.40" tomorrow. While flooding isn`t a great concern, it will be something to monitor since the ground is still so saturated and a few waterways are still very full. That previous sentence goes for the whole forecast package, both now and through the long term. Rainfall amounts Monday- Wednesday will be anywhere from 0.5" to 1". && .LONG TERM... (Tuesday Night through next Monday) Issued at 1122 AM CDT Mon May 13 2024 Scattered activity will continue through Tuesday night and will be slow to exit off the Plateau on Wednesday. We`ll have some more scattered activity around as the surface low spins NE out of the area. Looking aloft, ridging will start building in late Wednesday night. This will provide temporary relief from the rain for at least Thursday. This upper-air pattern is a progressive one, though, and another upper-level low developing over the SW will start pushing this way through the rest of the forecast period. This translates to an active and unsettled weather pattern for the weekend. Forecast rainfall amounts for Friday-Sunday range anywhere from 0.5" to near 2". Temperatures in the extended period will generally be in the low 80s for highs and overnight temps in the 60s. && .AVIATION... (06Z TAFS) Issued at 1240 AM CDT Tue May 14 2024 Current VFR/MVFR cigs will lower to MVFR later this morning as SHRA gradually spread across the area. Improvement back to VFR is anticipated by afternoon but widespread SHRA/TSRA will impact airports with tempo MVFR/IFR conditions and variable gusty winds to 25 knots. Showers will end late in the TAF period. South to southeast winds up to 10 knots are expected through tomorrow. && .PRELIMINARY POINT TEMPS/POPS... Nashville 78 62 77 61 / 90 60 10 0 Clarksville 75 60 75 60 / 80 40 10 0 Crossville 72 57 71 57 / 90 80 30 20 Columbia 78 60 77 59 / 80 50 10 0 Cookeville 75 59 72 58 / 80 80 30 10 Jamestown 74 57 71 57 / 90 80 30 20 Lawrenceburg 76 60 76 59 / 80 50 10 0 Murfreesboro 78 60 77 60 / 90 70 10 10 Waverly 75 60 76 59 / 90 40 10 0 && .OHX WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE.......Unger SHORT TERM...Baggett LONG TERM....Baggett AVIATION.....Shamburger