Area Forecast Discussion
Issued by NWS Knoxville/Tri Cities, TN-- Remove Highlighting --
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FXUS64 KMRX 221357 AAB
Area Forecast Discussion...UPDATED
National Weather Service Morristown TN
957 AM EDT Sat Apr 22 2017
Broad area of showers and weak thunderstorms continue to march
into the Cumberland Plateau and eventually into portions of the
central and southern Valley. This activity should continue to wane
over the next few hours as the associated 850 mb LLJ weakens as
it lifts north into KY between 15-18z. Still, with a stationary
boundary in place over the northern half of the area and a deep
warm cloud layer, the potential for localized flooding/flash
flooding is possible along the northern Cumberland Plateau and
Mtns area of SE KY/SW VA through 17-18z.
As this activity fades by early afternoon, some partial clearing
may allow the boundary layer to once again destabilize --
particularly across areas along and south of I-40. As a result,
some strong to marginally severe thunderstorms will be possible
late this afternoon and evening, with the best window being
21-01z. Uncertainty exists with just how unstable the environment
can get, but with better shear profiles, and progged MLCAPE values
between 500-1500 j/kg, some organized convection with damaging
winds and marginally severe hail is possible. Folks with outdoor
plans this afternoon should pay close attention to the weather
given the potential for lightning and locally heavy rainfall with
this activity as well.
.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN 81 57 64 52 / 90 90 80 30
Knoxville McGhee Tyson Airport, TN 77 56 60 50 / 80 90 90 40
Oak Ridge, TN 75 56 61 51 / 90 90 80 40
Tri Cities Airport, TN 74 53 58 48 / 90 90 100 60
NC...Flash Flood Watch from 2 PM EDT this afternoon through Sunday
afternoon for Cherokee-Clay.
TN...Flash Flood Watch from 2 PM EDT /1 PM CDT/ this afternoon
through Sunday afternoon for Anderson-Bledsoe-Blount Smoky
Mountains-Bradley-Campbell-Claiborne-Cocke Smoky Mountains-
Blount-North Sevier-Northwest Carter-Northwest Cocke-
Northwest Greene-Northwest Monroe-Rhea-Roane-Scott TN-
Sequatchie-Sevier Smoky Mountains-Southeast Carter-
Southeast Greene-Southeast Monroe-Sullivan-Unicoi-Union-
Washington TN-West Polk.
VA...Flash Flood Watch from 2 PM EDT this afternoon through Sunday
afternoon for Lee-Russell-Scott-Washington-Wise.