Alcoa, Tennessee Weather Forecast Discussion

128
FXUS64 KMRX 290537
AFDMRX
Area Forecast Discussion
National Weather Service Morristown TN
137 AM EDT Mon Sep 29 2025
...New DISCUSSION, AVIATION...
.KEY MESSAGES...
Updated at 134 AM EDT Mon Sep 29 2025
- After patchy morning fog, most areas will remain dry today with
chances for showers remaining in far eastern areas.
- Scattered showers and a few thunderstorms are possible on Tuesday,
focused mainly in the eastern half of the area.
- Dry seasonal fall weather is expected Wednesday through the
  weekend.
&&
.DISCUSSION...
Issued at 134 AM EDT Mon Sep 29 2025
Currently early this morning, broad ridging is in place across the
eastern U.S. with a weak embedded closed low. A jet streak is
centered to our east with Tropical Storm Imelda located in The
Bahamas at the time of this update. High pressure also remains in
place across the eastern U.S. Throughout the day, Imelda is forecast
to track north, well to the east of Florida before strengthening to
a hurricane and taking a sharp easterly turn. For today, most places
will stay dry with moisture advection and upper divergence
sufficient for rain chances in far eastern areas. Instability will
be minimal, supporting just showers. On Tuesday, another shortwave
will move through the area with a jet streak of 50 kts arriving from
the west. Moisture advection will strengthen, evidenced by PWATs
exceeding 1.5 inches for many areas, along with instability reaching
500 J/kg. With western portions of the area in the left entrance
region of this jet, upper convergence will limit ascent and overall
rain chances. Regardless, the latest CAMs continue the trend of
minimal coverage and little to no impact in our area.
By Wednesday, Imelda will advance further out into the Atlantic with
a closed low tracking along the northern Gulf. For our area,
broadening ridging will take place, in addition to expansion of
surface high pressure to the north with no effect from the closed
low. This broad pattern looks to continue through the end of the
week and the weekend, keeping rain chances out of the area. 500mb
heights remaining at or above 5,850m suggest daily highs to remain
mild but with subsidence promoting cooler nights than seen in recent
days.
&&
.AVIATION...
(06Z TAFS)
Issued at 134 AM EDT Mon Sep 29 2025
Patchy fog is expected through the early morning hours but
not to the level of what was seen last night. Currently, TRI is the
only site with high enough confidence for inclusion in the TAF with
IFR to MVFR forecast. Otherwise, VFR is expected to prevail through
the day with northeasterly winds of around 10 kts. A few showers are
possible later in the afternoon around TRI, but no aviation impacts
are expected.
&&
.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             85  65  85  64 /  10   0  20  10
Knoxville McGhee Tyson Airport, TN  83  63  82  62 /  10  10  20   0
Oak Ridge, TN                       83  63  83  61 /  10  10  20   0
Tri Cities Airport, TN              79  61  77  56 /  20  30  40   0
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
DISCUSSION...BW
AVIATION...BW

NWS MRX Office Area Forecast Discussion