Forecast Discussion


506
FXUS64 KMEG 300444
AFDMEG

Area Forecast Discussion
National Weather Service Memphis TN
1144 PM CDT Tue Jul 29 2025

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

.KEY MESSAGES...
Updated at 1143 PM CDT Tue Jul 29 2025

- Oppressive heat continues and will last through Thursday. Heat
  headlines are anticipated for Thursday as heat indices rise
  above 105 degrees and potentially reach or exceed 110 degrees.

- Shower and thunderstorm chances increase on Thursday ahead of a
  cold front. Temperatures this weekend will return to normal for
  early August.

&&

.DISCUSSION...
(Tonight through next Tuesday)
Issued at 1143 PM CDT Tue Jul 29 2025

Tranquil, yet stubbornly warm, weather currently resides over
much of the area. The ridging that has brought our heat over the
past two weeks still sits over the region, with a broad swath of
40 knot 500 mb flow over the upper Midwest into Canada. Although
some deamplification of the ridge will occur over the next 24
hours, dangerous heat concerns will persist through tomorrow and
likely Thursday. Heat indices tomorrow are likely to surpass 105
F, and possibly reach above 110 F through the afternoon. Given the
longevity and areal coverage of the ongoing heat wave, we have
decided to stick to an Extreme Heat Warning for tomorrow. Lastly,
have held off on issuing heat headlines for Thursday this period
given uncertainties in where the most extreme heat will occur.

By Thursday morning, the troughing to our north will begin to
impinge upon the upper riding across the southern CONUS. Surface
high pressure, containing refreshingly cooler air from Canada,
will slide south behind a cold front, reaching the Mid-South by
Thursday evening. The airmass ahead of this front will continue to
be very moist and warm, increasing the potential for some showers
and thunderstorms along the boundary as it passes through the
region. Models vary regarding the coverage of any convection, but
I do expect at least some convection to fire. Model soundings show
MLCAPE above 3500 J/kg in the vicinity of the boundary with weak
effective shear values. Therefore, any storms that do form should
pose mainly and isolated damaging wind risk and heavy rains
Thursday evening. Additional showers are possible overnight as the
front continues south.

After the front passes through the region Friday morning, highs
are anticipated to fall into the mid to upper 80s. Portions of
north Mississippi may see temperatures in the 90s, but there is
still some variability on how far north the front may remain
throughout the afternoon. Regardless, this weekend looks to be
much cooler and our first average to below-average weather in well
over two weeks. Furthermore, weather looks to be reasonably dry
with NBM PoPs in the 30s and relegated to northeast Mississippi.
Ensemble guidance is in good agreement that ridging will begin to
return again into the Middle of next week, but it is still too
far out to know how warm things may get again.

&&

.AVIATION...
(06Z TAFS)
Issued at 1143 PM CDT Tue Jul 29 2025

VFR conditions will continue through the TAF period. Isolated TSRA
will be possible across NE MS tomorrow afternoon, but not enough
confidence to include any mention for TUP at this time. Winds will
remain for the northeast, generally between 3 to 7 kts.

&&

.FIRE WEATHER...
Issued at 1143 PM CDT Tue Jul 29 2025

Fire weather conditions are not expected within this forecast
period due to high minimum relative humidity values in
combination with light 20 ft winds. A cold front will bring both
heat relief and higher rain chances Thursday through this weekend.

&&

.MEG WATCHES/WARNINGS/ADVISORIES...
AR...Extreme Heat Warning until 8 PM CDT Wednesday for ARZ009-018-
     026>028-035-036-048-049-058.

MO...Extreme Heat Warning until 8 PM CDT Wednesday for MOZ113-115.

MS...Extreme Heat Warning until 8 PM CDT Wednesday for MSZ001>017-
     020>024.

TN...Extreme Heat Warning until 8 PM CDT Wednesday for TNZ001>004-
     019>022-048>055-088>092.

&&

$$

PUBLIC FORECAST...JAB
AVIATION...CMA