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Area forecast discussion 
National Weather Service Morristown Tennessee
250 PM EDT Thursday Sep 18 2014

Short term (tonight through Saturday night)...current surface
analysis shows a weak cold front over the Ohio River valley...which
is expected to dissipate before reaching the forecast area. Radar
and satellite imagery reveal a convective complex over the western
Tennessee River valley moving southeastward...but its associated high
clouds will likely continue to move eastward across the forecast
area tonight. These clouds should limit the coverage of fog to
mainly around the waterways...and will thus mention patchy fog
developing after midnight. A large dome of high pressure...currently
centered over southern Canada...will slowly drift eastward across
the northeast on Friday...which will produce an easterly flow over
the Carolinas. This easterly upslope flow may create some isolated
showers on Friday over the southern Appalachians...and possibly
over northeast Tennessee and southwest Virginia as well. Thus...will include a
slight chance pop in these areas. As for temperatures...GFS and NAM
guidance numbers are in good agreement with maxes through
Saturday...but show some discrepancies with mins on Friday night
and Saturday night. Will compromise between the two with mins...and
will trend cooler than both with maxes (which has been the trend

Long term (sunday through thursday)...main system and only system of
concern through the extended will be a weak cold front sliding in
early in the period. Models trending a bit faster with the system
and will have highest probability of precipitation Sunday evening. Front has minimal
moisture and weak lift and coverage should be will keep
probability of precipitation around 30. Behind the front...surface high pressure builds in
and should dominate area weather through the rest of the extended
for dry conditions and seasonal temperatures.

Preliminary point temps/pops...
Chattanooga Airport, Tennessee 60 83 63 83 / 0 0 0 0
Knoxville McGhee Tyson Airport, Tennessee 57 81 61 81 / 0 0 0 0
Oak Ridge, Tennessee 57 81 61 81 / 0 0 0 0
Tri Cities Airport, Tennessee 52 78 57 78 / 0 20 0 0

Mrx watches/warnings/advisories...



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