Area Forecast Discussion
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FXUS64 KMRX 261908
Area Forecast Discussion
National Weather Service Morristown TN
308 PM EDT THU MAY 26 2016
.Short term (tonight and tomorrow)...
The main concern in the short term will be the convective line
moving E-SE across central KY this afternoon. The HRRR brings it
right to our northern Plateau counties at 00Z...then it dissipates
rapidly. SPC Mesoanalysis parameters show a less favorable
environment to support the storms in our area...and with the loss of
heating...the HRRR depiction of weakening storms looks reasonable
and will be followed. Will have a chance pop in the evening for the
Plateau...with a slight chance elsewhere. Some patchy fog may be
possible late tonight...but expected broken midlevel clouds should
prevent much widespready dense fog from developing.
A ridge off the Delmarva coast will continue to produce a southerly
low level flow over the Appalachians tomorrow...but there appears to
be a lack of mid/upper level forcing for lift. With little to no cap
in forecast soundings...this should result in scattered to isolated
showers and thunderstorms in the afternoon...with the mountains and
Plateau being favored areas.
.Long term (Friday night through Thursday)...
High pressure ridge along east coast remains strong friday night
into saturday saturday night but weak tropical low tries to develop
and move inland sunday into SC. At the same time persisitent
southerly flow around ridge will gradually increase moisture over
the eastern TN valley with an increasing chance of showers and
storms sunday into monday as a weak front approaches and possible
interaction from the east with weak tropical low. The ECMWF model
shows rain chances decreasing again tuesday as the front
dissipates. But the GFS brings more tropical moisture in from the
east tuesday keeping rain chances going. Another front will
approach wednesday and thursday with a good chance of afternoon and
evening showers and storms. Rainfall amounts will be highly
variable with the convective nature with some areas receiving much
less than others. Temperatures will remain above normal mostly mid
to upper 80s lower elevations with highs in the lower to mid 60s.
.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN 67 86 66 87 / 20 20 20 20
Knoxville McGhee Tyson Airport, TN 66 86 65 86 / 10 20 20 20
Oak Ridge, TN 65 85 65 86 / 20 20 20 20
Tri Cities Airport, TN 62 86 61 86 / 20 30 20 20