Area Forecast Discussion
Issued by NWS Knoxville/Tri Cities, TN

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000 FXUS64 KMRX 231930 AFDMRX Area Forecast Discussion National Weather Service Morristown TN 330 PM EDT Fri Jun 23 2017 .SHORT TERM (This Afternoon through Saturday)...
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The circulation around the remnants of Cindy is producing very favorable hodographs/shear for rotating updrafts. Main limitation is instability. Mixing has lowered dewpoints some across the region into the middle 60s to near 70, which is still quite high. As mid-level dry slot continues to move into the Region this afternoon instability will increase with MLCAPE increasing to 400-800 J/kg. Low CAPE and high shear environment will be conducive to the potential of low topped supercells. Latest meso-analysis data shows 0-1km shear of 30-35 and 0-6km shear of 40-50, so very high shear values STP values of 4-5 near Huntsville with 1-2 across the Plateau and southeast Tennessee. Besides the shear, strong low-level jet of 50-60kts later today will increase the potential of damaging winds due to bow radar features. Tornado watch has been issued for the western half of the area through 01Z. Circulation/low pressure will move east of the area late this evening/early morning. Next feature of interest will be frontal boundary that is moving across the Ohio Valley. This boundary will move across the area Saturday. Airmass along and ahead of the front will be unstable, so expected scattered/broken showers and thunderstorms, mainly during the morning Saturday. Dry air will pull into the region for Saturday afternoon with a return of sunshine. .LONG TERM...(Saturday night through Thursday)... Front will be south east of our area along with the precipitation and moisture from Cindy as well. A surface high pressure and mid level zonal/weak trough will then set up over our area. The drier air out of the northwest will help keep the skies mostly sunny the end of the weekend and into work week. Temperatures will remain below normal and winds will be light during this time frame. The next round of weather will hold off until the end of the work week into next weekend. The surface high will eventually move off the East coast and increased moisture will be allowed in from the Gulf of Mexico. Warmer temperatures will also be brought in and the combination of warm temperatures and increased moisture will lead to shower and thunderstorm activity over next weekend. This is still far enough away that the details are a bit fuzzy at this time for this next event.
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Chattanooga Airport, TN 72 85 64 84 / 80 60 10 0 Knoxville McGhee Tyson Airport, TN 70 82 62 81 / 90 50 0 0 Oak Ridge, TN 71 84 62 82 / 90 40 0 0 Tri Cities Airport, TN 68 82 59 79 / 80 50 0 10
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&& .MRX WATCHES/WARNINGS/ADVISORIES... NC...None. TN...Wind Advisory until 1 AM EDT Saturday for Blount Smoky Mountains- Cocke Smoky Mountains-Sevier Smoky Mountains. VA...None. && $$ is the U.S. government's official web portal to all federal, state and local government web resources and services.