452
FXUS64 KMEG 151146 AAA
AFDMEG

Area Forecast Discussion...UPDATED
National Weather Service Memphis TN
646 AM CDT Tue Sep 15 2026

...New AVIATION...

.KEY MESSAGES...
Issued at 646 AM CDT Tue Sep 15 2026

- Hazardous heat will persist into at least the middle of the
  week. Little rainfall is expected over the next seven days.

- An areawide Heat Advisory is in effect through 7 PM Today.
  Expect heat indices between 102 and 109 degrees.

- Temperatures are forecast to moderate slightly by early next
  week, returning closer to seasonal normals with highs near 90
  degrees.

&&

.DISCUSSION...
(Tonight through next Monday)
Issued at 1110 PM CDT Mon Sep 14 2026

Warm weather will continue through the Mid-South through the
forecast period. The feature responsible is an unseasonably
amplified high pressure system which has remained parked over the
southeastern CONUS through the last week. Current forecast
guidance remains bullish on the idea that this ridge will not
only remain over the Mid-South, but retrograde west and
strengthen through Thursday to around 600 dm. Surface
temperatures are likely to reach the upper 90s, if not rising at
or above 100 F. Regardless, surface dewpoints will stay around
70 F, leading to heat indices above 100 F. Most areas will see
105+ F heat indices Tuesday, prompting an areawide Heat Advisory
through Tuesday evening at 7 PM CDT. There is potential for the
Heat Advisory to be extended into Wednesday, but dewpoints may
manage to mix down to a point where afternoon heat index values
fail to reach the 105 F threshold for an advisory. Therefore, we
have opted to hold off on an extension, but there is a decent
probability that one will occur Tuesday.

In terms of precipitation, isolated, daily afternoon convection
is still possible even in the midst of a strengthening and
unseasonably strong ridge. RAP forecast soundings for both
Tuesday and Wednesday afternoons show a strengthening subsidence
inversion around 500 mb, but surface theta e values are
sufficiently high to produce surface based profiles supportive of
isolated convection. Therefore, expect pop-up showers and
thunderstorms both afternoons, especially across eastern Arkansas
and the Missouri Bootheel and along an arc across northern
Mississippi. West Tennessee is less likely to see any
precipitation since the ridge is forecast to be centered over
this region.

Through the middle of the week, a cutoff low will form along the
east coast and retrograde southwestward towards the Florida
Peninsula. This trough will eventually continue through the Gulf
along the Gulf Coast into the latter half of the week. In
response, the ridge is currently expected to flatten out to
around 590 - 594 dm, which would correspond to a slight decrease
in afternoon temperatures. However, the amplitude of the ridge,
even after weakening, would still be above normal for this time
of year. Therefore, above-normal temperatures in the mid 90s will
continue into next weekend. Ensembles have converged onto a
solution which then brings 500 mb heights down below 590 dm by
Sunday, but which also includes 850 mb temps around 20 C,
equivalent to 95 F through boundary layer mixing. So, even after
the ridge weakens substantially by this weekend, temperatures
will still continue to remain above normal. Isolated
precipitation associated with convection from the subtle height
falls could produce local heat relief. Forecast uncertainty
balloons exponentially after Saturday, but CPC guidance still
suggests that above normal temperatures can be expected into next
week.

&&

.AVIATION...
(12Z TAFS)
Issued at 646 AM CDT Tue Sep 15 2026

Light southerly winds and VFR will continue under a large upper
level high pressure ridge. Coverage of mid/late afternoon SHRA
will be too limited to warrant a PROB30 in the 12Z TAFs.

&&

.FIRE WEATHER...
Issued at 1110 PM CDT Mon Sep 14 2026

A low (< 10%) chance of patchy fog exists tonight. A warming
trend through the middle of the week will bring minimum relative
humidity values below 40% through the rest of the week with
10 hour fuels dropping to around 10%. Some locations could drop
to 30%. Fortunately, high pressure centered over the region will
keep 20 ft winds light. So, fire danger is expected to largely
stay low, but steadily drying fuels may start to increase fire
danger with no widespread wetting rains expected through this
week.

&&


.MEG WATCHES/WARNINGS/ADVISORIES...
AR...Heat Advisory until 7 PM CDT this evening for ARZ009-018-026>028-
     035-036-048-049-058.

MO...Heat Advisory until 7 PM CDT this evening for MOZ113-115.

MS...Heat Advisory until 7 PM CDT this evening for MSZ001>017-020>024.

TN...Heat Advisory until 7 PM CDT this evening for TNZ001>004-019>022-
     048>055-088>092.

&&

$$

PUBLIC FORECAST...JAB
AVIATION...PWB