442
FXUS64 KMEG 171730
AFDMEG

Area Forecast Discussion
National Weather Service Memphis TN
1230 PM CDT Mon Jun 17 2024

...New AVIATION...

.UPDATE...
Issued at 958 AM CDT Mon Jun 17 2024

Quick update. A plume of moisture rich air has arrived in the
Mid-South this morning. The latest SPC mesoanalysis shows an area
of PWAT values of 2.1 inches along and south of I-40. This plume
of moisture will continue to lift north across the region through
this evening. The main concern today will be instances of heavy
rainfall as a weak shortwave pivots north through the Mid-South
throughout the day. Rainfall rates will generally range between 2
and 4 inches with up to 6 inches with the deepest convection.
Minor nuisance flooding is possible, especially in heavily
populated areas.

The forecast is on track with no big changes needed. PoP coverage
will remain in the 40 to 60 range throughout much of the day with
scattered to numerous showers and thunderstorms. Outside of
showers and thunderstorms, heat indices will likely peak in the
mid to upper 90s.

AC3

&&

.SYNOPSIS...
Issued at 351 AM CDT Mon Jun 17 2024

Slightly cooler conditions are expected today and tomorrow as a
broad swath of rain moves in. Hot and dry weather returns by
midweek with a gradual warming trend. Rain chances will pick back
up early next week.

&&

.DISCUSSION...
(Today through Sunday)
Issued at 351 AM CDT Mon Jun 17 2024

KNQA radar is currently picking up some light returns moving up
from the Gulf Coast, foreshadowing what we`ll see this afternoon
and again tomorrow. Coverage and intensity of these showers and
eventually thunderstorms really starts to pick up around mid
morning today, maximizing in the late afternoon. These storms have
the potential to be very efficient rainfall producers; PWATs over
2 inches are above the 99th percentile of climatology between 18Z
and 00Z today. In addition to the cooling rain, ample moisture
will promote thicker cloud cover which will also help keep
temperatures on the mild side today and tomorrow. NBM
probabilistic guidance still suggests a low chance (10-40%) of
temperatures above 90 degrees today, increasing slightly to about
a 50% chance tomorrow.

We should dry back out on Wednesday as a very anomalously strong
upper level ridge begins to build over the Deep South. For
context, NAEFS 200 mb heights are over 3 standard deviations above
the mean for all hours from Wednesday afternoon to Sunday
morning. Said ridge will eventually settle somewhere over the
ArkLaTex region by late week, which spells out a warming trend for
the Mid-South. Heat and humidity return on Thursday, continuing
to warm further through the weekend. Forecast heat indices are
back to triple digits areawide by Sunday. There may be some
diurnally driven convection in the afternoons, but coverage will
be so sparse that PoPs are generally between 5-10% each day
through Saturday.

Another pattern shift is on the horizon early next week. Two
longwave troughs and their associated cold fronts look to dig
across the northern and central Plains, one on Sunday and another
following it next Tuesday. There`s still quite a bit of model
discrepancy but this generally suggests an increase in rain
chances (PoPs are about 20-40%) and perhaps a break from
oppressive heat and humidity early next week, depending on how far
south the fronts are able to make it. Stay tuned.

CAD

&&

.AVIATION...
(18Z TAFS)
Issued at 1230 PM CDT Mon Jun 17 2024

SHRA/TSRA is expected to continue across the Mid-South through
this evening which may produce instances of MVFR CIGS with
occasional IFR VIS. Later this evening, as precipitation
diminishes across the airspace, VFR conditions are expected to
prevail with the potential for shower activity across portions of
the Mid-South tomorrow afternoon.

&&

.MEG WATCHES/WARNINGS/ADVISORIES...
AR...None.
MO...None.
MS...None.
TN...None.
&&

$$

PUBLIC FORECAST...CAD
AVIATION...JPR