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Area forecast discussion 
National Weather Service Morristown Tennessee
308 PM EDT Friday Mar 27 2015

Short term...(tonight through sunday)...satellite pics this afternoon
show shortwave energy dropping south-southeast into the base of the upper trough
to our west. GFS and NAM models show good continuity in developing a
scattered band of rain or snow showers over parts of the forecast
area tonight. Really not much precipitation indicated (even sref)
for SW Virginia...so I did not mention much snow for the higher terrain
there. Also...forecast soundings show the moisture is very shallow
over SW Virginia with top of saturated column only around -10 degrees c.

Coordinated with gsp and opted to stay low on the snow accumulations
in the smokies...a dusting up to 2 inches above 2500 feet as in
previous grids. Thus...no Winter Weather Advisory with the main
story the freeze warning/watch. The freeze warning/watch product was
updated earlier.

Otherwise...little changes made for Saturday through Sunday with dry
weather briefly returning...courtesy of a surface and upper ridge
moving across the region. Favored the colder GFS MOS mins for
Saturday night...then a MOS blend on Sunday maxes as weak southerly
low level returns late.



Long term...(sunday night through Friday night)...a short wave
presses east across the northeastern U.S. Sunday night into Monday
generating some showers. Drier air will move into the southern
appalachian region later in the day Monday behind an associated cold
front. The dry period could last into middle week but forecast
uncertainty increases for the final three days of the extended
period with GFS and European model (ecmwf) offering differing solutions. Consall
blend keeps chance probability of precipitation going through Friday with a weak short wave
about Wednesday into Thursday followed by a little stronger system
to end the week. The good news is that a nice warming trend is in
the works with temperatures returning to normal or even a little
above...especially later in the week.



&&

Preliminary point temps/pops...
Chattanooga Airport, Tennessee 31 51 29 60 / 10 10 0 10
Knoxville McGhee Tyson Airport, Tennessee 27 45 24 57 / 40 0 0 10
Oak Ridge, Tennessee 27 46 25 57 / 30 0 0 10
Tri Cities Airport, Tennessee 25 40 19 53 / 30 10 0 10

&&

Mrx watches/warnings/advisories...
NC...freeze watch from late Saturday night through Sunday morning for
Cherokee-Clay.

Freeze warning from 2 am to 11 am EDT Saturday for Cherokee-Clay.

Tennessee...freeze watch from late Saturday night through Sunday morning for
Anderson-Bledsoe-Bradley-Campbell-Claiborne-east Polk-
Grainger-Hamblen-Hamilton-Hancock-Hawkins-Jefferson-Knox-
Loudon-Marion-McMinn-Meigs-Morgan-NW Blount-north Sevier-
northwest Carter-northwest Cocke-northwest Greene-northwest
Monroe-Rhea-Roane-Scott Tennessee-Sequatchie-southeast Monroe-
Sullivan-Union-Washington Tennessee-west Polk.

Freeze warning from 2 am EDT /1 am CDT/ to 11 am EDT /10 am CDT/
Saturday for Anderson-Bledsoe-Bradley-Campbell-Claiborne-
east Polk-Grainger-Hamblen-Hamilton-Hancock-Hawkins-
Jefferson-Knox-Loudon-Marion-McMinn-Meigs-Morgan-NW Blount-
north Sevier-northwest Carter-northwest Cocke-northwest
Greene-northwest Monroe-Rhea-Roane-Scott Tennessee-Sequatchie-
southeast Monroe-Sullivan-Union-Washington Tennessee-west Polk.

Virginia...freeze watch from late Saturday night through Sunday morning for
Lee-Scott-Washington.

Freeze warning from 2 am to 11 am EDT Saturday for Lee-Scott-
Washington.

&&

$$

Tg

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