Hail and Damaging Winds in Mississippi, June 16, 2023

Area Forecast Discussion
National Weather Service Memphis TN
1242 PM CDT Fri Jun 16 2023

...New AVIATION...

.SYNOPSIS...
Issued at 354 AM CDT Fri Jun 16 2023

Seasonally warm and humid conditions will prevail over the
Midsouth through the weekend. Showers and thunderstorms will be
possible each day, with peak rain chances on Sunday. The severe
thunderstorm risk area will extend along and south of a line from
Jonesboro to Memphis to Tupelo through Saturday.

Sunday will bring a chance of severe storms to most of the Midsouth,
ahead of a low pressure trough lifting out of the Great Plains.
Large hail and damaging winds will be the primary severe weather
threats on Sunday.

&&

.DISCUSSION...
(Today through Thursday)
Issued at 354 AM CDT Fri Jun 16 2023

Split upper level flow will prevail over the US and southern
Canada through the weekend, as a vestigial omega block pattern
remains. An upper level height ridge over the central and northern
Great Plains will continue to bring dry and warm conditions to
those areas. To the south of this ridge, a 75-90kt 250mb
subtropical jet will round the main subtropical height ridge,
centered over northern Mexico. This subtropical jet axis will
extend from the southern plains into the lower MS River valley.
Besides influencing the position of the main storm corridor, this
upper jet will provide spring-like bulk shear in proximity to
summer instability. As an example, last evening's 00Z FWD (Fort
Worth, TX) RAOB measured 5100 J/kg of mixed layer instability and
70kt of effective bulk shear.

Today's main storm track will extend from the Arklatex into
central and southern MS. This afternoon will likely see a
secondary storm corridor develop downstream of a weakening upper
low moving east/southeast of southern KS. Scattered storms will
likely form over central and northern AR by midafternoon, then
continue to develop southeast into the Midsouth. Areas along and
south of a Jonesboro to Memphis to Tupelo line appear most likely
to experience mid/late afternoon thunderstorms. Mixed layer CAPE
will prevail near 2000 J/kg over this area, accompanied by 35-45kt
effective bulk shear. Steeper midlevel lapse rates and slightly
greater instability will favor larger hail over the delta,
south and west of Memphis. The aforementioned weakening upper low
will drop southeast through the Midsouth tonight, providing a
continued chance of storms over north MS.

Upper level ridging will limit storm chances over the Midsouth on
Saturday. This ridging will be brief, ahead of a progressive
trough lifting through the plains. Storms will form over the
southern plains Saturday afternoon and likely enter eastern AR in
the predawn hours Sunday. This initial round of storms will be
tied to an initial shortwave. A second, possibly stronger shortwave
will eject through the Midsouth late Sunday afternoon and evening,
which will enhance severe thunderstorm chances during peak heating.

For early next week, the medium range models are consistent in
forming a cut-off low, centered over middle and east TN. Scattered,
mainly daytime storms will be possible east of the MS River. To
the west, an upper level ridge will build through the plains,
providing midsummer like heat and dry conditions.

PWB

&&

.AVIATION...
(18Z TAFS)
Issued at 1236 PM CDT Fri Jun 16 2023

Upstream convection over northwest and central Arkansas combined
with peak afternoon heating will be the focus for showers and
thunderstorms at TAF sites this afternoon and evening. Convective
initiation is anticipated to occur in the 19-21Z timeframe at TAF
sites and last into tonight. Instability may be weak enough to go
with prevailing VCSH for a few hours but enough elevated
instability justifies a mention of VCTS for the 4-8Z time frame
tonight. Mainly VFR conditions outside of thunderstorms and light
winds expected through the period.

CJC

&&

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

PUBLIC FORECAST...PWB
AVIATION...CJC