123
FXUS64 KMRX 191126
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
726 AM EDT Sat Apr 19 2025

...New AVIATION...

.SHORT TERM...
(Today through Sunday)
Issued at 253 AM EDT Sat Apr 19 2025

Key Messages:

1. Dry and unseasonably warm.

2. Low RH values This afternoon.

Discussion:

An anomalously strong 500mb ridge with 591-593 dam heights will
result in warm conditions across the Southeast CONUS this weekend,
and temperatures will run around 10 to 15 degrees above normal
across our forecast area. Record highs look high enough to likely
not be broken this weekend, but highs both days will likely not fall
very far short.

Daily Record High Maximum Temperatures

Date    Chattanooga    Knoxville      Tri-Cities     Oak Ridge
04-19   91(2002)       90(1941)       90(1941)       90(2002)
04-20   89(2002)       87(2002)       85(2023)       88(2002)

We will see varying amounts of high clouds around during the
weekend.  RH values will dip into the 30s in many locations this
afternoon with a few locations possibly dropping into the upper 20s.
South to southwest winds will also pick up to around 10 mph across
much of the area with some higher gusts. The low afternoon RH and
winds will be highlighted in the FWF.

&&

.LONG TERM...
(Sunday night through Friday)
Issued at 253 AM EDT Sat Apr 19 2025

Key Messages:

1. Weakening front brings showers/storms Monday into Monday night.
Overall severe risk is low because of limited instability.

2. It will remain warm for the remainder of the period, with a
shower or storm possible at times.

Discussion:

An upper level low will lift northeast from the Plains to the Great
Lakes region Sunday night into Monday, and this will flatten the
upper-level ridge over our region and bring a weakening cold front
in from the west during the Monday/Monday night time frame.  Models
do not agree on the timing, but overall the models suggest that
instability will be limited which will help to keep the severe
weather risk on the low side. However, model soundings do suggest
effective shear will approach 40kts, so some of the storms may be
organized enough to be strong to severe with damaging winds the
primary threat.

The front will struggle to clear the area Monday night and Tuesday,
and will likely stall near the southern parts of the forecast area.
This will keep the possibility of showers and storms in the forecast
for Tuesday especially south and east.

For the remainder of the period, models show lingering low level
moisture and instability appears favorable for diurnal convective
development, especially across the higher elevations each afternoon
or with any subtle MCV/shortwave features that may locally enhance
convective coverage. A more significant short wave may be
approaching by Friday, although models are currently struggling with
the timing of this feature.  Temperatures will run above normal
overall for the extended period.

&&

.AVIATION...
(12Z TAFS)
Issued at 512 AM EDT Sat Apr 19 2025

Will see VFR conditions for the period all sites. Winds will be
gusty from the south and southwest during the afternoon hours
today.


&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             88  63  86  63 /   0   0   0   0
Knoxville McGhee Tyson Airport, TN  86  61  86  63 /   0   0  10   0
Oak Ridge, TN                       85  61  86  62 /   0   0  10   0
Tri Cities Airport, TN              84  56  84  59 /   0   0  10   0

&&

.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&

$$

SHORT TERM...
AVIATION...