WW 516 SEVERE TSTM IL IN KY 262210Z - 270500Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 516
NWS Storm Prediction Center Norman OK
510 PM CDT Sun Jul 26 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Southern Illinois
Southwest Indiana
Western into Central Kentucky
* Effective this Sunday afternoon from 510 PM until Midnight CDT.
* Primary threats include...
Scattered damaging wind gusts to 70 mph likely
Isolated very large hail events to 2 inches in diameter possible
A tornado or two possible
SUMMARY...Widely scattered thunderstorms are forecast to continue to
develop and intensify through the early and mid evening. A couple
of the stronger storms will probably acquire supercell structure and
pose a risk for large hail, damaging gusts, and perhaps a tornado
through the early evening. As additional storms develop and outflow
becomes more prevalent, strong to severe gusts (55 to 70 mph)
capable of wind damage will become the primary severe hazard towards
the mid to late evening.
The severe thunderstorm watch area is approximately along and 60
statute miles east and west of a line from 50 miles northeast of
Salem IL to 30 miles southwest of Bowling Green KY. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU6).
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
2 inches. Extreme turbulence and surface wind gusts to 60 knots. A
few cumulonimbi with maximum tops to 550. Mean storm motion vector
33025.
...Smith
WW 0516 Status Updates
STATUS REPORT ON WW 516
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 ENE MDH
TO 35 WSW EVV TO 25 WSW OWB TO 5 S OWB TO 45 W SDF TO 35 W SDF.
..SQUITIERI..07/27/26
ATTN...WFO...ILX...PAH...LSX...IND...LMK...
STATUS REPORT FOR WS 516
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
ILC059-069-087-127-151-165-199-270140-
IL
. ILLINOIS COUNTIES INCLUDED ARE
GALLATIN HARDIN JOHNSON
MASSAC POPE SALINE
WILLIAMSON
KYC003-009-027-031-033-035-047-055-059-061-083-085-091-107-139-
141-143-145-149-157-171-177-183-213-219-221-225-227-233-
270140-
KY
. KENTUCKY COUNTIES INCLUDED ARE
ALLEN BARREN BRECKINRIDGE
BUTLER CALDWELL CALLOWAY
CHRISTIAN CRITTENDEN DAVIESS
EDMONSON GRAVES GRAYSON
HANCOCK HOPKINS LIVINGSTON
LOGAN LYON MCCRACKEN
MCLEAN MARSHALL MONROE
MUHLENBERG OHIO SIMPSON
MD 1749 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PORTIONS OF WESTERN INTO MIDDLE TENNESSEE
Mesoscale Discussion 1749
NWS Storm Prediction Center Norman OK
0734 PM CDT Sun Jul 26 2026
Areas affected...portions of western into middle Tennessee
Concerning...Severe potential...Watch possible
Valid 270034Z - 270130Z
Probability of Watch Issuance...60 percent
SUMMARY...Damaging gusts, a few of which may be severe, are expected
to accompany an approaching MCS. If the MCS maintains intensity
while approaching the KY/TN border over the next hour or so, a WW
issuance may be needed.
DISCUSSION...A cold-pool-driven MCS, with a history of wind damage,
continues propagate south-southeast at approximately 40 kts. It is
plausible that this MCS will maintain intensity given the
combination of 4500+ J/kg MLCAPE and 35-40 kts of effective bulk
shear (oriented perpendicular to the leading line) preceding the
cluster. Assuming this remains the case, the MCS is poised to enter
TN by around 0130Z. A Severe Thunderstorm Watch issuance may be
needed beforehand to address the impending severe threat if this MCS
maintains its current intensity.
..Squitieri/Smith.. 07/27/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...OHX...HUN...PAH...MEG...
LAT...LON 36168899 36408859 36538818 36638744 36628666 36388650
35848638 35348647 35138662 35028682 35038759 35068816
35098839 35208867 36168899
MOST PROBABLE PEAK WIND GUST...55-70 MPH
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0304 PM CDT Sun Jul 26 2026
Valid 262000Z - 271200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PORTIONS
OF THE UPPER MIDWEST AND WESTERN GREAT LAKES....
...SUMMARY...
Severe thunderstorms capable of large to very large hail, damaging
winds (possibly 75+ mph), and tornado risk remain likely from the
upper Mississippi Valley and Great Lakes southwestward into
Nebraska, mainly late this afternoon and tonight.
...20Z Update Upper Midwest...
No changes were made to the prior outlook. Severe storm development
remains likely this afternoon and evening as a very warm air mass
continues to destabilize. Weak, but sufficient, synoptic ascent
(evident in visible imagery) should aid in removing inhibition by
late this afternoon. Initial supercells developing over northeastern
MN and far northern WI will pose an all-hazards risk, including
locally severe wind gusts, very large hail, and a couple of
tornadoes. An MCS should eventually develop and track
south/southeast across WI and MI with a risk for damaging gusts and
a brief tornado or two through tonight.
...NE...
More isolated higher-based convection remains possible from central
and eastern NE, into western IA, and southeast SD late this
afternoon and evening. Very hot surface temperatures and moderate
buoyancy will support a few stronger storms with damaging wind and
isolated hail potential. Convective development appears most
probable along a thermally induced surface pressure trough, from
central NE northeastward late this afternoon.
...Mid MS Valley...
A very unstable and weakly capped air mass is present along a
diffuse differential heating zone from northwest IL, into northern
TN. Current expectations are for one or more clusters of
thunderstorms to develop along the boundary and ahead of a weak
mid-level wave/MCV across IA/IL, before spreading
south/southeastward into this evening. The extreme instability
(4000+ J/kg MLCAPE) and 25-35 kt of deep-layer shear should support
organized clusters, and eventually an MCS, with damaging winds
likely. A tornado or two is also possible with initial convection
along the boundary owing to extreme buoyancy, or any embedded QLCS
circulations with the expected MCS. See MCD#1742 for short-term
information.
Elsewhere, isolated damaging gusts remain possible with scattered
thunderstorms over the northern Rockies and across the Mid
Atlantic/Southeast. Weaker buoyancy/shear overlap suggests these
occurrences will be more sporadic, with limited storm
organization/longevity. See the prior discussion for additional
information.
..Lyons.. 07/26/2026
.PREV DISCUSSION... /ISSUED 1110 AM CDT Sun Jul 26 2026/
...Upper Midwest/Great Lakes...
Initial supercell storms are expected to develop across northern
MN/WI later this afternoon, aided by a favorably timed shortwave
impulse rounding the Plains upper ridge. Another MCV/shortwave
impulse located over the Dakotas at midday will also spread
east/southeast across southern/central MN this afternoon. These
features will provide support for one or more focused areas of
thunderstorm development. Initial supercells will pose an
all-hazards risk, including locally severe wind gusts, very large
hail, and a couple of tornadoes. With time into the evening, initial
supercells may grow into one or two small bowing MCSs. This storm
mode transition will support an increased risk for intense damaging
wind swaths this evening into tonight as convection spreads
southeast along a strong instability/moisture gradient across WI and
the Lake Michigan vicinity.
...Mid-Mississippi/Lower Ohio/Tennessee Valleys...
Multiple areas of strong to severe storms will be possible this
afternoon into tonight from near the MS River into IL/IN/KY/TN.
Thunderstorm development may be aided by a weak shortwave
impulse/MCV migrating southeast from IA at midday and into the Lower
OH Valley this evening. Storms are expected to develop along a
corridor of differential heating near/just east of the MS River
where mostly clear skies this morning have already resulted in
temperatures approaching 85-90 F, while scattered clouds further
east will maintain somewhat lower high temperatures. Thunderstorm
clusters this afternoon will pose a risk for severe/damaging wind
gusts. Sufficient clustering may occur and some upscale development
into a forward propagating bow may occur across the Lower Ohio
Valley vicinity this evening, and wind probabilities have been
increased to 30 percent for parts of southern IL/IN and western KY.
This activity could be maintained southward during the overnight
hours as far south as northern AL/GA given favorable instability and
sufficiently strong northwesterly flow aloft. Damaging wind gusts
could persist with this activity as it spreads south/southeast
across TN into AL/GA toward early Monday morning.
...NE/SD/IA...
A deeply mixed and hot boundary layer will develop this
afternoon/early evening in the vicinity of a weak surface trough
from NE into southeast SD/northwest IA. Very steep lapse rates aloft
will foster 1500-2000 J/kg MLCAPE. Vertically veering wind profiles
and increasing northwesterly flow aloft will provide 25-35 kt
effective shear magnitudes and a few organized cells/clusters may
develop by late afternoon. Damaging wind gusts of 60-80 mph would be
the main hazard with this activity. While temperatures are somewhat
warm aloft, the strongest storms could produce sporadic large hail.
...Mid-Atlantic/Carolinas/Southeast GA/Northern FL...
Upper troughing will persist today across the East, though some
enhancement to northwesterly flow aloft is expected. Relatively cool
conditions, weak lapse rates, and the potential influence of smoke
will temper destabilization across the Mid-Atlantic. Nevertheless,
MLCAPE 1000 J/kg amid 25-35 kt of effective shear may support
occasional organized storms capable of producing locally damaging
gusts.
Stronger heating/destabilization is expected farther south across
the Carolinas into GA/FL. Deep-layer flow/shear will be somewhat
weaker compared to farther north, but may still be sufficient for
transient storm organization with sporadic locally damaging winds
possible.
...Southeast MT/northern WY/Black Hills vicinity...
High-based convection is expected to develop this afternoon along
the northern periphery of the upper ridge, with the greatest storm
coverage expected across parts of northern Wyoming and southern
Montana. Overall buoyancy is expected to remain weak, but inverted-v
profiles will support a threat of strong to localized severe gusts
as storms spread eastward toward the Black Hills before weakening
into mid/late evening.
SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0437 PM CDT Sun Jul 26 2026
Valid 281200Z - 031200Z
Upper-level troughing is forecast across portions of the Pacific
Northwest through much of the workweek, with the main upper-level
low remaining offshore. Meanwhile, periodic mid-level shortwaves
will rotate through the base of the trough and over the area in the
southwest flow aloft. The strongest and most well-defined shortwave
is forecast Day 5/Thursday. Upper-level ridging across the southern
High Plains Day 3/Tuesday is expected to gradually build westward
into next weekend. Thereafter, longer-range ensemble guidance
continues to suggest that the aforementioned upper-level low may
move onshore next weekend, though timing details remain uncertain.
...Northwestern US...
Weaker flow aloft will tend to limit the fire weather threat across
the Pacific Northwest through much of the week. Though, locally
elevated fire weather conditions appear likely most days due to
lingering dry and breezy conditions amidst receptive fuels. While,
thunderstorm chances may return Day 5/Thursday as the aforementioned
shortwave trough impinges on the area, confidence in 10% coverage
remains a bit too low to introduce probabilities at this time.
Nevertheless, this will be monitored considering the forecast
sensitivities with multiple large fires ongoing across the area.
Longer range guidance continues to suggest dry and breezy conditions
may return to the Northwest sometime next weekend as the offshore
trough moves inland. At this time, confidence remains too low to
introduce Critical probabilities.
...Southern High Plains...
Hot, dry, and breezy conditions are likely across portions of the
southern High Plains through much of the workweek. While near
elevated fire weather conditions appear likely, recent fuel guidance
suggests the fuelscape remains mostly mixed and winds are forecast
to generally remain at or below elevated thresholds. Nevertheless,
fuels are expected to continue drying due to the multiple days of
hot, dry, and breezy conditions, which may necessitate fire weather
highlights in later forecasts.
..Elliott.. 07/26/2026
...Please see www.spc.noaa.gov/fire for graphic product...
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