497
FXUS64 KMEG 032339
AFDMEG

Area Forecast Discussion
National Weather Service Memphis TN
639 PM CDT Thu Apr 3 2025

...New AVIATION...

.KEY MESSAGES...
Updated at 636 PM CDT Thu Apr 3 2025

-Severe storms and flooding rainfall are expected to continue
 through Saturday.

-An Enhanced Risk of severe weather is in effect Tonight through
 Saturday.

-A High Risk of excessive rainfall is in effect tonight through
 Saturday.

-Total rainfall amounts through Sunday could exceed 10 to 15 inch
 range along and north of I-40. This is not your average flood
 risk. Generational flooding with devastating impacts is possible.

&&

.DISCUSSION...
(This evening through next Wednesday)
Issued at 400 PM CDT Thu Apr 3 2025

...A multi-day severe weather outbreak and generational flooding
continues...

Mainly elevated thunderstorms have occurred this afternoon on
the cool side of a quasi-stationary front. The latest surface
analysis places the aforementioned boundary from just north of the
ArkLaMiss extending northeast through Oxford, MS and into
Savannah, Tennessee. Along and south of the boundary is where an
all-hazards threat will continue through late this evening. The
warm sector is characterized by a tight gradient of 1500-2500
J/kg of MLCAPE, 60 to 65 knots of bulk shear, and effective SRH
of 200 to 400 m2/s2. Any storms that form in the area, will have
to the ability to quickly grow upscale and produce all hazards. A
couple of strong (EF-2+) tornadoes are possible, as is large hail
(>2 inches). Along and north of the boundary, a large hail and
damaging wind threat will exist, as LCLs are a bit higher and
storms will be mostly elevated.

The main threat today still remains flash flooding, as multiple
waves of training thunderstorms continue to pivot NE across west
Tennessee. Most of west Tennessee, received 5 to 7 inches of
rainfall over the past 24 hours, 5 to 10 inches forecast across
portions of west Tennessee. South of I-40, rainfall totals will
range from 3 to 7 inches.

We may see a notable break in the severe weather and flooding
threat on Friday morning and afternoon. Upper level heights will
build ahead of a deepening trough near the ArkLaTex. This will
help lift the front north of the area tomorrow afternoon. Hi-res
models are only generating isolated to scattered modest coverage
of showers and thunderstorms tomorrow afternoon. However, if any
storms can reach their convective temperature, severe
thunderstorms will be possible. Large hail, damaging winds, and
tornadoes are the main threats. The highest threat of severe
weather will be situated along the front, where a surface low is
progged to ride along it tomorrow night.

The front is expected to push slightly north and east as it
stalls near the I-40 corridor early Saturday. A robust shortwave
will eject on Saturday and generate significant lift across the
region. Multiple waves of very heavy rainfall will fall along and
near the front and increase the flood threat considerably. A high
risk (4/4) of flash flooding is in effect. All types of flooding
are possible with flash flooding as the most life-threatening type
on Saturday. The most significant flooding impacts of the week
will likely occur on Saturday. There is a high chance of
significant river flooding, washed-out roadways, and even water
rescues.

We will finally see a break late Sunday through the middle of next
week as surface high pressure builds into the region.

AC3

&&

.AVIATION...
(00Z TAFS)
Issued at 636 PM CDT Thu Apr 3 2025

Stationary boundary expected to lift north tonight across the area
tonight. Additional showers and thunderstorms expected this
evening at all sites except TUP where confidence in convective
development is much lower. MVFR/IFR conditions expected tonight
with some improvement possible on Friday.

&&

.MEG WATCHES/WARNINGS/ADVISORIES...
AR...Flood Watch through Sunday morning for ARZ009-018-026>028-035-
     036-048-049-058.

MO...Flood Watch through Sunday morning for MOZ113-115.

MS...Flood Watch through Sunday morning for MSZ001>005-007-008-
     010>014-020.

     Flood Watch from late Friday night through Sunday afternoon for
     MSZ006-009-015>017-021>024.

TN...Flood Watch through Sunday morning for TNZ001>004-019>022-
     048>055-088>092.

&&

$$

PUBLIC FORECAST...AC3
AVIATION...CJC