RSS Mesoscale Discussions from Storm Prediction Center
WW 241 SEVERE TSTM AR LA MS 231515Z - 232300Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 241
NWS Storm Prediction Center Norman OK
1015 AM CDT Sat May 23 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Southeast Arkansas
Central and Eastern Louisiana
Mississippi
* Effective this Saturday morning and evening from 1015 AM until
600 PM CDT.
* Primary threats include...
Scattered damaging wind gusts to 70 mph possible
A tornado or two possible
SUMMARY...An organized linear cluster of storms will continue
east-northeastward today with wind damage as the most common hazard.
The severe thunderstorm watch area is approximately along and 80
statute miles east and west of a line from 70 miles northeast of
Monroe LA to 65 miles southwest of Mc Comb MS. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU1).
PRECAUTIONARY/PREPAREDNESS ACTIONS...
REMEMBER...A Severe Thunderstorm Watch means conditions are
favorable for severe thunderstorms in and close to the watch area.
Persons in these areas should be on the lookout for threatening
weather conditions and listen for later statements and possible
warnings. Severe thunderstorms can and occasionally do produce
tornadoes.
&&
AVIATION...A few severe thunderstorms with hail surface and aloft to
1 inch. Extreme turbulence and surface wind gusts to 60 knots. A few
cumulonimbi with maximum tops to 500. Mean storm motion vector
25025.
...Guyer
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WW 0241 Status Updates
STATUS FOR WATCH 0241 HAS NOT BEEN ISSUED YET
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MD 0836 CONCERNING SEVERE THUNDERSTORM WATCH 241... FOR NORTHEAST LOUISIANA INTO CENTRAL MISSISSIPPI
Mesoscale Discussion 0836
NWS Storm Prediction Center Norman OK
1205 PM CDT Sat May 23 2026
Areas affected...Northeast Louisiana into central Mississippi
Concerning...Severe Thunderstorm Watch 241...
Valid 231705Z - 231900Z
The severe weather threat for Severe Thunderstorm Watch 241
continues.
SUMMARY...The threat for wind damage will continue into central
Mississippi this afternoon. Brief tornadoes also may occur,
particularly close the the MCV circulation.
DISCUSSION...Filtered surface heating continues ahead of an
MCV-driven convective line. The strongest surface heating has
occurred in central Mississippi where temperatures are in the low
80s F. KPOE VAD shows around 40 kt of flow within the lowest 3 km
after the MCV passed. This should promote at least some threat for
wind damage as low-level lapse rates continue to steepen ahead of
the activity. The southern extent of the threat is the most
uncertain given the influence of convection along the central Gulf
Coast. While overall low-level shear remains weak, KPOE VAD did show
an increase to around 200 m2/s2 0-3 km SRH just ahead of the MCV.
Brief tornadoes remain possible this afternoon.
..Wendt.. 05/23/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...JAN...LIX...LCH...SHV...
LAT...LON 31498955 31319002 31219080 31079161 31179188 31639207
32039263 32399305 32529298 33269158 33379037 33098946
32638910 32198922 31498955
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
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SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0750 AM CDT Sat May 23 2026
Valid 231300Z - 241200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE SOUTHERN PLAINS AND CENTRAL HIGH PLAINS...WESTERN AND CENTRAL
GULF COAST...GEORGIA INTO SOUTH CAROLINA...AND ACROSS OHIO...
...SUMMARY...
Isolated severe thunderstorms are possible today across the lower
Mississippi Valley and into parts of Texas. Other isolated severe
storms are possible in portions of the Southeast, Ohio, and the
central High Plains.
...Southern High Plains...
Weak mid-level flow and an ill-defined surface pattern aptly
characterize the severe-potential setup for later today into the
evening across this region. Residual low-level moisture and steep
700-500 mb lapse rates (reference the 12 UTC Midland, TX raob; 8.7
deg C/km) in combination with strong heating will result in moderate
instability developing by mid-late afternoon. Scattered
thunderstorms are forecast to develop from near the CO/OK-TX
Panhandles border region southward into the Edwards Plateau.
Isolated large hail and severe gusts will be the primary severe
hazards with the stronger storms. Some clustering is expected
during the evening before this activity diminishes by late evening.
...South-central and Southeast Texas/Southern Louisiana...
In the coastal areas of the western and central Gulf, very moist air
will be in place. Surface dewpoints in the lower to mid 70s F will
contribute to moderate instability by midday. Thunderstorms will
form along sea breeze boundaries during the early to mid afternoon.
A few severe wind gusts and a brief tornado will be possible.
Farther north over the Ark-La-Miss, some heating ahead of a
north-south band of showers/thunderstorms associated with an MCV
over OK, will contribute to a marginally supportive wind-damage
risk. Have expanded low-wind probabilities to account for
observational trends of a semi-organized band of storms continuing
east into the Ark-La-Miss during peak heating.
...Georgia/South Carolina...
A weak mid-level disturbance over MS/AL this morning will move
east-northeastward today. Adequate heating of a moist boundary
layer will yield 500-1000 J/kg MLCAPE by early afternoon and
scattered showers/thunderstorms are forecast. Deep-layer shear will
support some multicellular organization in the form of a few
thunderstorm clusters. The stronger water-loaded downdrafts will
potentially yield a localized wind-damage risk during the afternoon
before this threat wanes by early evening.
...Central High Plains...
Latest model guidance shows isolated thunderstorms developing late
this afternoon within a belt of stronger cyclonic mid-level flow
associated with a north-central U.S. larger-scale mid-level trough.
The 30-40 kt 500-mb flow and steepened surface to 400-mb lapse rates
may support a couple of locally stronger thunderstorms to develop
towards early evening. Locally severe hail/wind will be the threat
with these storms.
...Ohio...
Southwesterly mid-level flow will be in place over the Ohio Valley
and lower Great Lakes today. At the surface, an axis of low-level
moisture will be located from eastern Kentucky into central and
northern Ohio, where dewpoints will be in the mid to upper 60s F. As
instability increases during the day, scattered thunderstorms are
expected to develop and move northeastward across the instability
corridor. RAP forecast soundings in central Ohio at 21Z have 0-6 km
shear near 30 knots with 0-3 km storm-relative helicity around 150
m2/s2. This could be enough for an isolated tornado threat.
..Smith/Weinman.. 05/23/2026
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SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1134 AM CDT Sat May 23 2026
Valid 231630Z - 241200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER
MISSISSIPPI VALLEY AND SOUTHERN HIGH PLAINS/WEST TEXAS...
...SUMMARY...
Severe thunderstorms are possible today mainly across the Lower
Mississippi Valley and parts of West Texas. Other more isolated
severe storms are possible in portions of the Southeast, Ohio, and
the central High Plains.
...Lower Mississippi Valley...
An ongoing semi-well-organized cluster of storms appears to be aided
by an MCV, and will likely continue east-northeastward today across
the ArkLaMiss and broader parts of Mississippi, to the north of more
extensive weaker convection closer to the coast in southern
Louisiana. Ample heating ahead of the cluster and steepening
low-level lapse rates will support wind potential aside from a
modest MCV-related flow enhancement. A brief tornado could also
occur, although thunderstorm wind damage is most probable.
...West Texas/Southern High Plains...
Relatively weak mid-level flow and an ill-defined surface pattern
aptly characterize the severe-potential setup for later today into
the evening across this region. Residual low-level moisture and
steep 700-500 mb lapse rates (reference the 12 UTC Midland, TX raob;
8.7 deg C/km) in combination with strong heating will result in
moderate instability developing by mid-late afternoon, stronger with
southward extent across the Texas South Plains into southwest Texas.
At least widely scattered thunderstorms are forecast to develop from
near the Colorado/Panhandles border region southward into the
Edwards Plateau. Isolated large hail and severe wind gusts will be
the primary severe hazards. A gradual clustering is expected during
the evening before this activity diminishes by late evening.
...Georgia/South Carolina...
A weak mid-level disturbance will move east-northeastward today.
Ahead of it, adequate heating of a moist boundary layer will yield
500-1000 J/kg MLCAPE by early afternoon and scattered
showers/thunderstorms are forecast. Deep-layer shear will support
some multicellular organization in the form of a few thunderstorm
clusters. The stronger water-loaded downdrafts will potentially
yield a localized wind-damage risk during the afternoon before this
threat wanes by early evening.
...Central High Plains...
Isolated thunderstorms are expected to develop late this afternoon
within a belt of stronger cyclonic mid-level flow associated with a
north-central U.S. larger-scale mid-level trough. The 30-40 kt
500-mb flow and steepened surface to 400-mb lapse rates may support
a couple of locally stronger thunderstorms late this afternoon
through early evening. Locally severe hail/wind will be the threats
with these storms.
...Ohio...
A couple of rotating storms could develop regionally this afternoon
within a belt of residually strong low-level flow. A brief/low-end
tornado threat may exist.
..Guyer/Lyons.. 05/23/2026
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SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1225 PM CDT Sat May 23 2026
Valid 241200Z - 251200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM WESTERN KS
INTO CENTRAL/EASTERN NE...SOUTHEAST SD...SOUTHWEST MN...NORTHWEST
IA...
...SUMMARY...
Strong to locally severe storms are possible from parts of the
central Plains into the Upper Midwest, mainly Sunday afternoon and
evening. Isolated large to very large hail and localized severe
gusts will be possible.
...Central Plains into the Upper Midwest...
A mid/upper-level shortwave trough initially over the Upper Midwest
will move over the Great Lakes region on Sunday. Broad southerly
flow between a surface ridge near the mid MS Valley and a lee trough
over the High Plains will result in some moisture return into parts
of the central Plains and Upper Midwest, though the magnitude of
this moisture return remains somewhat uncertain. Steep midlevel
lapse rates and relatively cool midlevel temperatures atop the
returning moisture will result in moderate to locally strong
destabilization by late afternoon.
Broad midlevel height rises are expected across the region, in the
wake of the departing shortwave trough. However, guidance suggests
that one or more weak midlevel vorticity maxima may aid in at least
isolated diurnal thunderstorm development near a weak surface
trough/dryline from central NE into southeast SD/southwest MN.
Deep-layer flow will remain generally modest, but veering wind
profiles and 30-40 kt of effective shear will conditionally support
supercells, if surface-based development can be sustained. Large to
very large hail and localized severe gusts could accompany any
supercell development during the afternoon and evening.
A Level 2/Slight Risk upgrade was considered for parts of the
region, but due to uncertainties regarding low-level moisture and
storm coverage, have opted to maintain a Level 1/Marginal Risk, with
a conditional area highlighting very large hail potential, should
any sustained supercells develop.
...Southeast/southern Appalachians...
Scattered thunderstorm development is again expected across the
region, within a moist and uncapped environment. A belt of 20-30 kt
midlevel flow to the east of the mid/upper trough across TX will
provide modest deep-layer shear, but weak midlevel lapse rates will
tend to limit updraft intensity. Locally damaging wind cannot be
ruled out with convection across the region, but the
organized-severe threat currently appears too limited and nebulous
to include probabilities at this time. If a robust MCV emerges from
extensive convection near the Gulf Coast, then somewhat more
organized severe potential could evolve through the day.
...LA Gulf Coast/Lower MS Valley vicinity...
Widespread convection is expected to persist from D1/Saturday into
D2/Sunday across parts of the LA Gulf Coast and lower MS Valley, as
the nearly stationary mid/upper trough over TX interacts with rich
moisture. Generally weak flow and lapse rates are currently expected
to limit the organized-severe threat. Any more organized potential
for a brief tornado or locally damaging wind would likely be
contingent on MCV development, but this scenario remains highly
uncertain at this time.
...Lower OH Valley/Allegheny Plateau...
Scattered thunderstorms will be possible across parts of the Ohio
Valley and Allegheny Plateau during the afternoon, in association
with the mid/upper trough moving across the Great Lakes region.
Modest midlevel flow will overspread the region and isolated strong
storms will be possible, but weak lapse rates and modest buoyancy
are expected to limit severe potential.
..Dean.. 05/23/2026
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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1122 AM CDT Sat May 23 2026
Valid 231700Z - 241200Z
...NO CRITICAL AREAS...
No changes were needed for the Day 1 Fire Weather Outlook update.
Please see previous forecast discussion below.
..Williams.. 05/23/2026
.PREV DISCUSSION... /ISSUED 1251 AM CDT Sat May 23 2026/
...Synopsis...
Upper-level troughing will persist across the northern Great Plains
and Midwest today, with ridging in place across much of the
Southeast/East Coast. Upper-level ridging will also gradually build
across much of the western CONUS through the period. At the surface,
a series of frontal systems will progress across the Great Plains
and eastern CONUS, with several mid-level perturbations promoting
the potential for wetting rainfall across much of the Southern
Plains and eastern US.
Warming temperatures under the gradually building ridge will support
RH reductions to 10-20% across much of the Southwest and portions of
the Great Basin this afternoon. Weak surface pressure gradient
magnitudes and, subsequently, generally light surface winds will
largely temper broad fire weather concerns across the region.
Sustained westerly/southwesterly winds of 10-15 mph may promote
locally elevated fire weather concerns in favored gap/terrain areas,
however.
Mid-level moisture atop deep, well-mixed boundary layer profiles may
support weak buoyancy and isolated high-based convection over higher
terrain across portions of the western Great Basin into far
northeastern California and southern Oregon this afternoon.
Generally limited lightning potential and sub-critical fuels should
temper the overall lightning ignition threat, however.
...Please see www.spc.noaa.gov/fire for graphic product...
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