367
FXUS64 KMEG 261831
AFDMEG

Area Forecast Discussion
National Weather Service Memphis TN
131 PM CDT Thu Jun 26 2025

...New DISCUSSION...

.KEY MESSAGES...
Updated at 131 PM CDT Thu Jun 26 2025

- Hot and humid conditions will continue through the rest of the
  week. A Heat Advisory remains in effect areawide until Friday
  night.

- Isolated afternoon showers and thunderstorms will occur each
  day. A strong to severe storm could occur this afternoon along
  and south of Interstate 40 with damaging winds being the primary
  threat.

&&

.DISCUSSION...
(This evening through next Wednesday)
Issued at 131 PM CDT Thu Jun 26 2025

Rex blocking continues today as an upper low slides westward along
the southern periphery of the heat dome over the southern CONUS.
Outflow from thunderstorms last night has pushed through the
region this morning, bringing cooler air and some clouds across
the eastern half of the area. This has kept temperatures at bay so
far today and will likely limit the spatial extent of locations
that experience 100+ heat indices. However, no changes were made
to the heat advisory given the duration of the current heat wave
and the expectation for 100+ heat indices area wide tomorrow.

In the meantime this afternoon, storms are already beginning to
develop along and ahead of the aforementioned outflow boundary in
W TN and E AR. MLCAPE greater than 3000 J/kg in combination with
weak to nonexistent shear will promote pulse mode thunderstorms
carrying the potential for hybrid microbursts. Thunderstorm
coverage will diminish quickly after sunset with the chance for
patchy fog tomorrow morning.

The upper low is expected to keep eating away at the ridging
across the area into this weekend. A meager decrease in 500 mb
heights is expected, but will not be enough to meaningfully
change the prevailing temperature forecast from hot to cool.
Instead, a net cooling of only a few degrees will occur with heat
indices falling to around 100 with higher values possible within
the MS River Delta. No additional heat headlines were added for
Saturday or Sunday, but are likely to be introduced in upcoming
forecast periods in the southwestern half of the region.
Scattered, pulse- like thunderstorms are possible with limited
concerns for damaging winds.

A zonal upper pattern will take over next week, as opposed to the
amplified ridging present now. Guidance keeps the main belt of
westerlies along the Canadian border alongside a few tropical
perturbations in the Gulf. Therefore, Monday`s heat indices will
also be similar to this weekends. ECMWF and GFS guidance amplify
a shortwave trough over the eastern Great Lakes Tuesday, which in
turn strengthens high pressure over the northern Plains. Any other
time of the year this would normally be linked to a frontal
passage, but neither model seems keen on taking a front as far
south as TN and AR, let alone MS. So, current thinking is that
this boundary will wash out or stall by the time it makes it to
our latitude Tuesday evening with only a few showers and storms
to show. Highs after Tuesday will be in the upper 80s and low 90s
with heat indices from 90 - 100 F through the end of the period.

&&

.AVIATION...
(18Z TAFS)
Issued at 1216 PM CDT Thu Jun 26 2025

Storms are firing along outflow boundaries in far northwest TN and
in east Arkansas and should increase in coverage throughout the
afternoon hours. South to southwest winds will prevail through the
TAF cycle, generally 7kts or less during daylight hours, 3-4 kts
overnight. Additional storms are expected to develop by 18z
tomorrow. Patchy 3-5SM fog/BR is possible overnight near TUP and
MKL.

&&

.FIRE WEATHER...
Issued at 131 AM CDT Thu Jun 26 2025

High moisture will continue through the period with minimum
relative humidity values unlikely to drop below 40%. This, in
combination with light 20 foot winds, precludes and concerns for
fire weather through the period. However, heat headlines will
continue through tomorrow with more hot and humid weather expected
through the weekend.

&&

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

MO...Heat Advisory until 9 PM CDT Friday for MOZ113-115.

MS...Heat Advisory until 9 PM CDT Friday for MSZ001>017-020>024.

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

&&

$$

PUBLIC FORECAST...JAB
AVIATION...JDS