Mesoscale Discussion 0824
NWS Storm Prediction Center Norman OK
0900 AM CDT Fri May 22 2026

Areas affected...Parts of MS/AL into southern TN

Concerning...Severe potential...Watch possible 

Valid 221400Z - 221600Z

Probability of Watch Issuance...40 percent

SUMMARY...Some increase in the brief-tornado and localized
damaging-wind threat is possible with time into early afternoon.

DISCUSSION...A midlevel vorticity maximum and attendant weak surface
low are moving across eastern AR this morning. An arc of convection
associated with this system extends across western TN into
northern/eastern MS and western AL. The 12Z JAN/BMX soundings depict
rich moisture and poor midlevel lapse rates, with around 25-35 kt of
deep-layer shear and modestly enlarged low-level hodographs noted on
regional VWPs. 

Filtered heating and modest destabilization in advance of this
convective band may allow for some intensification through the
morning into the early afternoon, though weak midlevel lapse rates
may continue to hamper updraft strength. A belt of moderate
low-level flow associated with the ejecting shortwave trough will
maintain favorable low-level SRH, and transient supercell structures
will continue to be possible through the morning, with a
brief-tornado threat. A localized wind-damage threat may also
increase with time, especially in areas where stronger heating and
steepening of midlevel lapse rates occur. While uncertainty remains
regarding coverage and magnitude of the threat, watch issuance is
possible given the possibility of some increasing tornado potential
with time.

..Dean/Hart.. 05/22/2026

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...OHX...BMX...HUN...MOB...MEG...JAN...LIX...

LAT...LON   31678926 32648919 33538883 34258918 34628969 34938959
            35348926 35628864 35778758 35598669 34658673 33708686
            33248690 32478709 30668744 30398904 31158921 31678926 

MOST PROBABLE PEAK TORNADO INTENSITY...85-110 MPH
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0749 AM CDT Fri May 22 2026

Valid 221300Z - 231200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR THE TEXAS
PANHANDLE AND NORTHWEST TEXAS INTO SOUTHWEST OKLAHOMA...

...SUMMARY...
Thunderstorms with large to very large hail and severe gusts are
possible late this afternoon into the evening in parts of the
southern High Plains.

...Southern High Plains...
Modest cyclonic mid-level flow will extend from the Interior West
through the base of the trough over the south-central U.S. 
Water-vapor imagery shows a weak disturbance migrating east across
the Permian Basin this morning.  A seasonably moist airmass
maintained via southeasterly low-level flow will heat and become
moderately to strongly unstable by mid afternoon.  

Model forecast soundings show relatively cool 500-mb temperatures
(near -14 deg C) with steep low- to mid-level lapse rates later this
afternoon.  Strong heating will locally erode appreciable remaining
convective inhibition and widely scattered thunderstorms will likely
develop by late afternoon.  Although westerly flow will likely
remain modest (20 kt from 600 to 200 mb), strongly veering flow will
result in 25-30 kt effective shear, supporting supercells initially.
Large to very large hail will be possible with the more intense
updrafts.  Increasing storm coverage during the evening will tend to
promote some upscale growth into a linear cluster with severe gusts
becoming more prevalent.  The risk for severe gusts (60-80 mph) may
focus during the 00-03 UTC period before a gradual waning in
coverage/intensity by late evening.  

...Central Gulf Coast States/Ohio and Tennessee Valleys...
Water-vapor imagery shows a disturbance moving northeastward across
the ArkLaMiss this morning and moving towards western portions of
TN/KY and the lower OH Valley.  Surface analysis indicates a moist
airmass featuring dewpoints ranging from the upper 60s over TN to
the lower 70s over the central Gulf Coast.  Despite widespread cloud
cover, some thinning of the cloud shield is expected as temperatures
slowly warm through the early afternoon.  Models generally show weak
buoyancy (500-1000 J/kg MLCAPE) and skinny CAPE profiles and
tempered lapse rates (reference the Nashville and Birmingham 12 UTC
raobs).  However, models show some enhancement/strengthening of
925-500 mb flow moving northeastward across MS/AL into TN through
the mid-late afternoon.  As a result, some enlargement of hodographs
will likely occur during the diurnal heating cycle and a few weak
supercell structures will probably develop.  Yet, the ongoing
thunderstorm band over eastern MS may be ill timed as it moves
northeastward across western/northern AL through midday. 
Nonetheless, an isolated risk for a tornado seems possible over much
of this general region.  A risk for isolated damaging gusts may also
accompany some of the stronger thunderstorms before this activity
wanes by the early evening.

...Mid Missouri Valley...
An upper-level trough and an associated mid-level jet streak will
move northeastward today across the north-central U.S. At the
surface, an axis of low-level moisture will be in place from eastern
Kansas northward into eastern Nebraska.  Ahead of the trough,
scattered thunderstorms will develop in the afternoon along and near
the moist axis. Surface dewpoints in the lower to mid 60s F will
contribute to weak instability with MLCAPE likely peaking in the 500
to 1000 J/kg range across eastern Nebraska.  RAP forecast soundings
near Omaha suggest that 0-6 km shear will reach 35 knots as the
trough approaches this afternoon, which would support the
development of low-topped supercells capable of isolated severe wind
gusts and hail.  The severe threat is expected to persist into the
early evening.

..Smith/Weinman.. 05/22/2026