219
FXUS64 KMEG 201710
AFDMEG

Area Forecast Discussion
National Weather Service Memphis TN
1210 PM CDT Mon Jul 20 2026

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

.KEY MESSAGES...
Issued at 1209 PM CDT Mon Jul 20 2026

- Dangerous heat continues through Tuesday evening, with high
  temperatures expected to reach the upper 90s; the Extreme Heat
  Warning and Heat Advisory remain in effect for the entire
  region.

- A cold front will move through Tuesday evening, bringing a risk
  of scattered strong to severe thunderstorms capable of producing
  damaging winds and heavy rainfall.

- Conditions will trend drier and slightly cooler late this week
  as the front clears, followed by a return of heat for the
  weekend.

&&

.DISCUSSION...
(This evening through next Sunday)
Issued at 1209 PM CDT Mon Jul 20 2026

A hot and humid day is underway as of 11 AM with air temperatures
already in the upper 80s and lower 90s with triple digit heat
index values. Expect temperatures to continue to rise this
afternoon, into the mid to upper 90s, as ridging amplifies. A few
showers and thunderstorms may develop this afternoon across north
Mississippi, along a shortwave from the tropical airmass in the
Gulf. While not anticipating any severe thunderstorms with this
activity, hefty downpours are likely in any development.

Tuesday will be the hottest day of the summer as upper 90s are
expected across the entire region. Areas along and west of the
river have low, but still notable, probabilities of 100F or
higher air temperatures Tuesday afternoon. A few additional
counties will likely need to be added to the Extreme Heat Warning
for tomorrow. This amount of heat will aid in very steep low
level lapse rates as well as SBCAPE. An approaching frontal
boundary will sink south and spark scattered thunderstorms in its
wake and tap into this very unstable, tropical airmass. The
better height falls look to dive over southeast Kentucky into
Middle Tennessee, but with moisture and lift, a strong to severe
thunderstorm cannot be ruled out tomorrow afternoon and evening.
Damaging winds and torrential rainfall would be the primary
threats. The RRFS simulated radar is much more robust in
coverage, but has similar timing to the other CAMs, with storms
firing on the KY/TN border between 4-6 PM. Would not expect the
severe weather window to go beyond 2 AM, but showers and
thunderstorms will likely continue until near sunrise Wednesday
across north Mississippi. Storms are expected to be progressive
and move swiftly through the region. Due to projected storm
speed, the 90th percentile QPF through Thursday morning is less
than an inch.

Once the cold frontal boundary clears the region, subtle
northwest flow aloft will filter in drier and cooler conditions.
Temperatures in the 80s to lower 90s prevail through the end of
the work week, which is leaning slightly below normal for the
latter half of July. Unfortunately, subtle upper level ridging
will build in from the west for the weekend. This will warm
temperatures back up into the 90s area wide by Sunday. The NBM
does bring medium to high probabilities of triple digit heat
index values making a return for areas along and west of the
Mississippi River. Long term guidance favors a deep, upper trough
over Quebec which will strengthen northwest flow aloft and could
keep the Mid-South in a troughing pattern to close out July.

DNM

&&

.AVIATION...
(18Z TAFS)
Issued at 1209 PM CDT Mon Jul 20 2026

VFR conditions will likely prevail through the current TAF
period. Scattered -TSRA will move through the area this
afternoon, although confidence is low. Have included mentioned at
MEM as VCTS and at TUP, where there are slightly higher
probabilities, as a PROB30. Otherwise, variable winds will become
S after 00Z, remaining around or below 5 kts.

&&

.FIRE WEATHER...
Issued at 1209 PM CDT Mon Jul 20 2026

Light 20-ft winds and minimum RH values remaining above 40% will
keep fire weather concerns minimal through the period.

&&


.MEG WATCHES/WARNINGS/ADVISORIES...
AR...Extreme Heat Warning until 9 PM CDT Tuesday for ARZ009-018-
     026>028-035-036-048-049-058.

MO...Extreme Heat Warning until 9 PM CDT Tuesday for MOZ113-115.

MS...Extreme Heat Warning until 9 PM CDT Tuesday for MSZ007-010-011-
     020.

     Heat Advisory until 9 PM CDT Tuesday for MSZ001>006-008-009-
     012>017-021>024.

TN...Heat Advisory until 9 PM CDT Tuesday for TNZ001>004-019>022-
     048>055-088>092.

&&

$$

PUBLIC FORECAST...DNM
AVIATION...CMA