Flash Flood Warning 12, NWS Morristown, TN

Area Forecast Discussion
National Weather Service Morristown TN
745 PM EDT Sat Mar 15 2025

...New UPDATE, AVIATION...

.UPDATE...
Issued at 740 PM EDT Sat Mar 15 2025

Updated forecast to freshen up wording. Strong to severe
thunderstorms are moving northeast across the southern valley and
southern plateau at this hour. Heavy rainfall is occurring with
these storms with their slow eastern movement.

&&

.UPDATE...
Issued at 602 PM EDT Sat Mar 15 2025

Updated forecast to include Tornado watch for counties in east
Tennessee and Cherokee County NC.

&&

.SHORT TERM...
(Tonight)
Issued at 236 PM EDT Sat Mar 15 2025

Key messages:

1. Significant severe weather event expected for our forecast area
this evening into the overnight hours. Damaging winds will be the
primary hazard, along with the possibility of tornadoes.

2. Flooding will be a concern tonight, with the most likely area
for flooding being the Cumberland Plateau and Southern TN Valley.

3. High winds in the mountains will persist through tonight,
coupled with very dry fuels, so fire danger levels will remain
elevated and a Red Flag Warning is in effect through this evening.

4. Strong winds expected area-wide today and tonight. A High Wind
Warning is in effect for the East Tennessee mountains and
foothills. A Wind Advisory is in effect for the rest of the
region.

Discussion:

Satellite and obs show partial clearing is occurring across much
of the area. This is not good news for the expected evening
storms. The morning rain has led to dewpoints in the lower to mid
60s across much of the southern and central TN Valley and
Cumberland Plateau. There is a notable dewpoint gradient running
N-S from around LNP to Newport, likely due to downslope drying to
the east of that line where dewpoints are in the upper 40s. Areas
west of this line are developing ample instability to maintain
thunderstorms that are approaching from the west.

The HRRR appears to have a good handle on the location of ongoing
storms in Middle/West TN and the MS/AL border. It shows these
storms reach our Plateau counties between 22-23Z. The convective
mode will be mainly linear with damaging wind gusts and embedded
cells capable of producing tornadoes. While the southern Plateau
and TN Valley will have the highest tornado potential due to
backed surface winds, the threat cannot be ruled out farther north
as well up to the aforementioned boundary. Bottom line is that
everyone in East TN should stay weather aware tonight, have
multiple ways to receive warnings, and act quickly when a warning
is issued.

So far, the gradient winds have been slow to materialize in the
TN Valley. Winds in the mountains have been under High Wind
Warning criteria since sunrise, but we are still expecting winds
to increase everywhere as the LLJ picks up near sunset and the
strengthening surface low tracks from the lower MS Valley into
West TN and KY. No changes will be made to the current Wind
Advisory and High Wind Warning. The lack of rain so far in the
mountains along with the expected winds will continue RFW
conditions until the rain arrives around midnight.

Flooding will be a concern overnight. The morning rainfall
produced from 1 to 2.5 inches in the western half of the area,
priming the pump for additional flooding problems tonight, when an
additional 1-3 inches of rain will be possible in those same
areas. Flash flood guidance west of I-75 is only 1 inch, with
3-hour being only about 1.25 inches. Based on this, the FA.A will
add a few counties to the east, and include Knoxville.

&&

.LONG TERM...
(Sunday through next Saturday)
Issued at 236 PM EDT Sat Mar 15 2025

Key Messages:

1. Cooler temperatures Sunday into Monday and especially Monday
morning with lows generally in the 30s.

2. Increasing temperature trend and dry the first half of next week,
with the next cold front not expected until Thursday timeframe.

3. Cooler end to the work week and weekend.

Discussion:

The upper trough will cross our area on Sunday. Under the trough,
steep lapse rates will keep scattered showers going through the
afternoon hours. A secondary cold front will cross the area late
in the day, bringing colder temperatures Sunday night with lows in
the 30s. On Sunday night, the precipitation will be exiting the
region, but there is a possibility that the peaks of the mountains
get a dusting of snow before sunrise Monday morning. Daytime on
Monday won't see temperatures rebound much with all areas expected
to be below seasonal normals.

However, this cold spell won't last for very long after another
night of cold temperatures Monday night/Tuesday morning, as things
quickly warm up Tuesday heating back up into the 60's/70's with
strong ridging and surface high pressure working in tandem with the
very sunny skies. This set up stays in place for Wednesday and then
the temperature roller coaster takes another drop off for the back
half of the week with a quick moving system moving through the Ohio
Valley/Great Lakes Region. The timing/location/strength of this late
week system at this time are indicating that it should be overall
much weaker than the this previous weekend system as most of the
synoptic forcing looks like it could be pulling out to the north as
it moves near the eastern Tennessee Valley.

Of higher confidence is the cooler temperatures behind the main
front with a chilly end to the week and most of the weekend with
temperatures looking to remain at or below seasonal normals for
multiple days. Taking a peak just beyond the end of the forecast we
could be in for another round on the temperature roller coaster with
very warm and chilly days looking possible.

&&

.AVIATION...
(00Z TAFS)
Issued at 740 PM EDT Sat Mar 15 2025

Showers and thunderstorms will affect CHA next several hours and
will be moving into TYS shortly and TRI in a few hours. Strong
gusty winds will continue from the southeast to south and then
shift to the west southwest later tonight with gusts to about 35
knots. VFR ceilings except in thunderstorms so could drop below
3000 feet. Visibilities will drop to MVFR in thunderstorms through
the evening. After midnight behind the thunderstorms expect
ceilings to drop to MVFR. Ceilings will become VFR again by around
12Z. Gusty southwest winds Sunday afternoon.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             56  68  35  60 / 100  40  20   0
Knoxville McGhee Tyson Airport, TN  57  68  34  56 / 100  50  40  10
Oak Ridge, TN                       56  66  34  57 / 100  60  30  10
Tri Cities Airport, TN              58  68  36  53 / 100  60  50  10

&&

.MRX WATCHES/WARNINGS/ADVISORIES...
NC...Wind Advisory until 8 AM EDT Sunday for Cherokee-Clay.

TN...Wind Advisory until 8 AM EDT /7 AM CDT/ Sunday for Anderson-
     Bledsoe-Bradley-Campbell-Claiborne-Grainger-Hamblen-
     Hamilton-Hancock-Hawkins-Jefferson-Knox-Loudon-Marion-
     McMinn-Meigs-Morgan-North Sevier-Northwest Blount-Northwest
     Carter-Northwest Cocke-Northwest Greene-Northwest Monroe-
     Rhea-Roane-Scott TN-Sequatchie-Sullivan-Union-Washington TN-
     West Polk.

     Flood Watch through Sunday morning for Anderson-Bledsoe-Bradley-
     Campbell-Claiborne-East Polk-Hamilton-Knox-Loudon-Marion-
     McMinn-Meigs-Morgan-Northwest Blount-Northwest Monroe-Rhea-
     Roane-Scott TN-Sequatchie-Southeast Monroe-Union-West Polk.

     High Wind Warning until 8 AM EDT Sunday for Blount Smoky
     Mountains-Cocke Smoky Mountains-East Polk-Johnson-Sevier
     Smoky Mountains-Southeast Carter-Southeast Greene-Southeast
     Monroe-Unicoi.

     Red Flag Warning until 11 PM EDT this evening for Blount Smoky
     Mountains-Cocke Smoky Mountains-East Polk-Johnson-Sevier
     Smoky Mountains-Southeast Carter-Southeast Greene-Southeast
     Monroe-Unicoi.

VA...Wind Advisory until 8 AM EDT Sunday for Lee-Russell-Scott VA-
     Washington VA-Wise.

&&

SHORT TERM...TD
LONG TERM....DGS
AVIATION...TD

Hazardous Weather Outlook...UPDATED
National Weather Service Morristown TN
343 PM EDT Sat Mar 15 2025

NCZ060-061-TNZ012>018-035>047-067>074-081>087-098>102-VAZ001-002-
005-006-008-161945-
Cherokee-Clay-Scott TN-Campbell-Claiborne-Hancock-Hawkins-
Sullivan-Johnson-Morgan-Anderson-Union-Grainger-Hamblen-
Northwest Cocke-Cocke Smoky Mountains-Northwest Greene-
Southeast Greene-Washington TN-Unicoi-Northwest Carter-
Southeast Carter-Roane-Loudon-Knox-Jefferson-Northwest Blount-
Blount Smoky Mountains-North Sevier-Sevier Smoky Mountains-
Sequatchie-Bledsoe-Rhea-Meigs-McMinn-Northwest Monroe-
Southeast Monroe-Marion-Hamilton-Bradley-West Polk-East Polk-Lee-
Wise-Scott VA-Russell-Washington VA-
343 PM EDT Sat Mar 15 2025 /243 PM CDT Sat Mar 15 2025/

This Hazardous Weather Outlook is for portions of southwest North
Carolina...east Tennessee and southwest Virginia.

.DAY ONE...This Afternoon and Tonight

High winds will continue in the mountains and foothills through
tonight with winds up to 80 mph this evening. This will also
raise concerns for the spread of any ongoing wildfires in the
region. See the High Wind Warning now in effect for more details.
A Wind Advisory has been issued for the rest of the region with
gusts up to 45 mph expected. Winds will peak this evening.

A Red Flag Warning is in effect for the East Tennessee mountains
and foothills through late this evening. Very strong winds and dry
fuels will bring continued fire danger. Confidence increases in
moderate to heavy rain for the mountains late this evening and
overnight.

A severe weather outbreak is likely across portions of the
eastern United States today into tonight with the greatest threat
in east Tennesse being along the Cumberland Plateau, southeast
Tennessee, and southwest North Carolina. Widespread and
significant damaging winds are likely. There is also a threat for
tornadoes and large hail.

Also, with multiple rounds of storms, there is a threat for flash
flooding by this evening, especially west of Interstate 75.

.DAYS TWO THROUGH SEVEN...Sunday through Friday

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter reports may be needed this weekend with any severe
thunderstorms and flash flooding today and tonight.

Preliminary Local Storm Report
National Weather Service Morristown TN
717 PM EDT Sat Mar 15 2025

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0711 PM     Tstm Wnd Dmg     1 SE Griffith Creek     35.28N 85.54W
03/15/2025                   Marion             TN   Public

            Several trees down.

&&

dh

Preliminary Local Storm Report
National Weather Service Morristown TN
742 PM EDT Sat Mar 15 2025

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0735 PM     Tstm Wnd Dmg     2 NNW Palio             35.49N 85.34W
03/15/2025                   Bledsoe            TN   Public

            Trees down. Trees were twisted.

&&

dh

Preliminary Local Storm Report
National Weather Service Morristown TN
748 PM EDT Sat Mar 15 2025

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0729 PM     Non-Tstm Wnd Dmg 2 NE Pigeon Forge       35.81N 83.54W
03/15/2025                   Sevier             TN   Public

            Pieces of awnings from roofs detached, sheet
            metal from porches peeled back.

&&

Preliminary Local Storm Report
National Weather Service Morristown TN
829 PM EDT Sat Mar 15 2025

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0823 PM     Hail             6 NE Oak Ridge          36.02N 84.23W
03/15/2025  E1.00 Inch       Anderson           TN   Public

            Report from mPING: Quarter (1.00 in.).

&&

Preliminary Local Storm Report
National Weather Service Morristown TN
842 PM EDT Sat Mar 15 2025

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0800 PM     Non-Tstm Wnd Gst 3 ESE Wears Valley      35.70N 83.61W
03/15/2025  M85 MPH          Sevier             TN   Park/Forest Srvc

            At the Cove Mountain Wind Tower.

&&

Preliminary Local Storm Report
National Weather Service Morristown TN
853 PM EDT Sat Mar 15 2025

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0704 PM     Non-Tstm Wnd Gst 2 S Round Mountain      35.81N 82.96W
03/15/2025  M60 MPH          Cocke              TN   Public

            Report from the United Methodist Church
            Sterchi Lodge near the Appalachian Trail.

&&