Scientific Forecaster Discussion
fxus64 kmrx 140231 aaa
Area forecast discussion...updated
National Weather Service Morristown Tennessee
931 PM EST Wed Nov 13 2019
Besides some increasing high level clouds, clear sky prevails
across the region. Surface ridging remains across the southern
Appalachians. Due to the mostly clear sky and calm winds, good
radiational cooling conditions exits. Have lowered min
temperatures most locations for tonight, as well as, hourly
temperatures to match current conditions.
Have also added patchy fog mainly for steam fog development near
area lakes lakes and streams.
Have a good night.
00z taf discussion.
VFR conditions will prevail throughout the taf period. There will
be a gradual increase in high and mid level clouds Thursday. Surface
ridging into the Tennessee Valley will keep winds light and
/issued 617 PM EST Wed Nov 13 2019/
short term (tonight and thursday)...
still quiet following the significant frontal passage, and a
clear, dry, and cold night is on tap beneath high pressure area.
For Thursday, a weak closed low over south Texas at 12z will open up
in response to a northern branch shortwave that will dig into the
middle Mississippi Valley. As the Gulf Coast shortwave moves
eastward across the Gulf Coast, it will spread showers across much
of the deep south and southeastern U.S. The cloud shield will
move into our forecast area during the day, and we may even see
some late afternoon 20 pct pops for our extreme southeast corner
of the forecast area.
Long term (thursday night through wednesday)...
a weak system moving along the Gulf Coast late Thursday will have
enough moisture to squeeze out some light rain as moisture
spreads north across southwest North Carolina and southeast
Tennessee and farther north in the Smoky Mountains Thursday night
into Friday morning. Another weak front will slide southeast from
the Ohio Valley Thursday and settle east of the mountains Friday
morning. The front will reinforce the colder temperatures over the
area. Will keep precipitation chances lower than guidance, mostly
20 percent or less in the smokies and southeast Tennessee but
higher Cherokee and Clay counties in North Carolina. Temperatures
will be much warmer Thursday night/Friday morning mostly lower to
mid 30s...slightly cooler extreme northern edges where cloud cover
will be less. The upper trough/or closed low across the lower MS
valley will move slowly east away from the forecast area by Friday
night. Friday clouds will decrease slowly from the southeast and
mountains but highs will stay cold in the mid 40s to lower 50s.
Friday night through the weekend high pressure will become
reestablished with some ridging aloft with a slow warming trend.
Nights will stay cool in the mid 20s to lower 30s. Sunday night
into Monday another front and upper trough moves into the
Mississippi Valley. The ridge may be too strong for this front to
move into the area with European model (ecmwf) model keeping precipitation mainly
north over the Ohio Valley. Moisture return will being Sunday
night and continue Monday. Will have slight chance rain eastern
areas late Monday and Monday night. Tuesday into Wednesday upper
trough shifts east with temperatures staying in the 50s daytime
and 30s at night.
Preliminary point temps/pops...
Chattanooga Airport, Tennessee 26 49 37 53 31 / 0 10 10 10 10
Knoxville McGhee Tyson Airport, Tennessee 23 48 34 50 30 / 0 10 10 10 10
Oak Ridge, Tennessee 23 49 33 51 29 / 0 10 0 0 10
Tri Cities Airport, Tennessee 17 47 31 50 26 / 0 10 10 10 10