499
FXUS64 KMEG 190541
AFDMEG

Area Forecast Discussion
National Weather Service Memphis TN
1241 AM CDT Wed Aug 19 2026

...New DISCUSSION, AVIATION, FIRE WEATHER...

.KEY MESSAGES...
Issued at 1241 AM CDT Wed Aug 19 2026

- Dangerous heat is expected to persist on Wednesday with Heat
  Advisories and Extreme Heat Warnings in effect.

- A Slight (level 2 out of 5) Risk for severe weather is in place
  for portions of northeastern Arkansas, the Missouri Bootheel,
  and West Tennessee Wednesday night into early Thursday. Damaging
  winds and localized heavy rainfall are the main threats.

&&

.DISCUSSION...
(Today through Tuesday)
Issued at 1241 AM CDT Wed Aug 19 2026

Surface analysis this evening places a quasi-stationary front
from the Central Plains into portions of the Lower Mississippi
Valley with the front effectively just to the south of the
forecast area. Convection Tuesday afternoon was limited to a
single strong thunderstorm over northeast Mississippi. Otherwise,
dry conditions have persisted across the Mid-South into the
evening with temperatures in the 80s to around 90 degrees with
surface dewpoints in the 70s.

The aforementioned quasi-stationary boundary will begin to lift
back north as a warm front overnight into Wednesday. Short-term
models including CAMs indicate convective development over
eastern Kansas and western Missouri overnight gradually spreading
southeast and weakening as it approaches the Mid-South by sunrise
Wednesday. This activity may leave some remnant outflow
boundaries up near the MO/KY border with mainly rain free
conditions occurring during the day, especially along and south
of I-40.

Temperatures across the Mid-South will rise back into the mid 90s
to lower 100s again on Wednesday. These very hot temperatures
combined with dewpoints in the lower to middle 70s will produce
heat index values between 105 to 112 degrees across the Mid-
South. The Extreme Heat Warning was expanded north to Jonesboro
and up to portions of the Memphis metro area as short-term
guidance indicates the potential for moisture to pool in this
region. A Heat Advisory was also expanded up to the Missouri
border where heat index values may reach Advisory criteria.
Otherwise, no other modifications were made to the Advisory and
Warnings in effect.

Latest guidance indicates showers and thunderstorms will develop
Wednesday afternoon over southern Missouri and slowly spread
southeast into the Mid-South Wednesday night into early Thursday
morning. Considerable uncertainty remains between guidance with
the latest 00Z NAM keeping most of the activity north of the Mid-
South with other model solutions suggesting development after 06Z
Thursday. Moderately steep mid-level lapse rates, MLCAPE values
between 1500-2500 J/kg, and precipitable water values around
2 inches support the potential for severe thunderstorms. Model
soundings show some favorable storm relative helicities with
clockwise curved hodographs but also feature parcels becoming
elevated throughout the night with a capping inversion below
850 mb. Thus, confidence in any tornado development remains very
low at best. Damaging winds will be the primary threat, with a
secondary threat of localized heavy rainfall and perhaps some
marginally severe hail.

Shower and thunderstorm chances will continue Thursday into
Thursday night as a mid-level trough pushes into the eastern
U.S., allowing a cold front to push through the Mid-South. This
front will bring some relief with cooler temperatures, especially
over portions of West Tennessee into the upcoming weekend.

&&

.AVIATION...
(06Z TAFS)
Issued at 1241 AM CDT Wed Aug 19 2026

VFR conditions will continue to prevail through this morning.
Remnant outflow from a complex of thunderstorms overnight across
MO, western KY, and southern IL will impact MEM/JBR/MKL.
Confidence is highest in a northerly wind shift at JBR, but
enough uncertainty remains at MEM/MKL to warrant the inclusion of
only VRB for now. This aspect of the forecast is expected to be
refined in the 12z TAFs.

Winds are expected to recover through Wednesday afternoon ahead
of a weak surface low over northern AR. These southerlies will
prevail through the end of the period. After 00z, convection is
expected to fire along the AR/MO and TN/KY borders which will
gradually spread south overnight. As of this TAF package, only
enough confidence exists at JBR to include TSRA toward the end of
the TAF, but potential exists for both MEM and MKL to see the
inclusion of TS in future TAF issuances.

&&

.FIRE WEATHER...
Issued at 1241 AM CDT Wed Aug 19 2026

Fire danger potential remains low as 20 ft winds remain light,
but minimum relative humidity values could locally drop below 40%
Wednesday afternoon across portions of east Arkansas and
northwest Mississippi. Fog potential remains low (<10%) due to
dry soils. Wetting rain chances increase Wednesday night into
Thursday morning as a cold front moves south into the area. Some
thunderstorms are possible during this time, which will be
accompanied by a chance for damaging winds and heavy rainfall.

&&


.MEG WATCHES/WARNINGS/ADVISORIES...
AR...Heat Advisory from 11 AM this morning to 8 PM CDT this evening
     for ARZ009-018.

     Extreme Heat Warning from 11 AM this morning to 8 PM CDT this
     evening for ARZ026>028-035-036-048-049-058.

MO...Heat Advisory from 11 AM this morning to 8 PM CDT this evening
     for MOZ113-115.

MS...Heat Advisory from 11 AM this morning to 8 PM CDT this evening
     for MSZ002>005-009-013>017-021>024.

     Extreme Heat Warning from 11 AM this morning to 8 PM CDT this
     evening for MSZ001-007-008-010>012-020.

TN...Heat Advisory from 11 AM this morning to 8 PM CDT this evening
     for TNZ019-048-050>053-089>091.

     Extreme Heat Warning from 11 AM this morning to 8 PM CDT this
     evening for TNZ049-088.

&&

$$

PUBLIC FORECAST...CJC
AVIATION...JAB