WW 572 SEVERE TSTM NE SD 120320Z - 121100Z
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 572
NWS Storm Prediction Center Norman OK
1020 PM CDT Tue Aug 11 2026
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Far North-Central Nebraska
South-Central South Dakota
* Effective this Tuesday night and Wednesday morning from 1020 PM
until 600 AM CDT.
* Primary threats include...
Scattered damaging winds and isolated significant gusts to 75
mph likely
Scattered large hail and isolated very large hail events to 2
inches in diameter possible
SUMMARY...Ongoing cluster of thunderstorms, including a supercell,
is forecast to continue southeastward into south-central South
Dakota and far north-central Nebraska tonight. Ample buoyancy exists
across this region, suggesting the storms will remain severe as they
move through. Primary risk is strong to severe wind gusts, including
the potential for gusts to 75 mph. Large hail could occur as well,
with an isolated instance or two of very large hail (i.e. 2" in
diameter) possible.
The severe thunderstorm watch area is approximately along and 50
statute miles north and south of a line from 70 miles northwest of
Valentine NE to 50 miles north northeast of Oneill NE. For a
complete depiction of the watch see the associated watch outline
update (WOUS64 KWNS WOU2).
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.
&&
OTHER WATCH INFORMATION...CONTINUE...WW 570...
AVIATION...A few severe thunderstorms with hail surface and aloft to
2 inches. Extreme turbulence and surface wind gusts to 65 knots. A
few cumulonimbi with maximum tops to 500. Mean storm motion vector
28035.
...Mosier
WW 0572 Status Updates
STATUS REPORT ON WW 572
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 50 WNW VTN
TO 45 N VTN TO 45 SSW PIR TO 20 NW 9V9.
..KERR..08/12/26
ATTN...WFO...LBF...FSD...UNR...ABR...
STATUS REPORT FOR WS 572
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
NEC015-017-031-089-103-149-120640-
NE
. NEBRASKA COUNTIES INCLUDED ARE
BOYD BROWN CHERRY
HOLT KEYA PAHA ROCK
SDC003-015-023-043-053-121-123-120640-
SD
. SOUTH DAKOTA COUNTIES INCLUDED ARE
AURORA BRULE CHARLES MIX
DOUGLAS GREGORY TODD
TRIPP
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
WW 0570 Status Updates
STATUS REPORT ON WW 570
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 50 SE JMS TO
55 ESE BIS TO 45 E BIS.
REMAINING VALID PORTION OF WW MAY BE ALLOWED TO EXPIRE AS SCHEDULED
AT 12/06Z.
..KERR..08/12/26
ATTN...WFO...BIS...FGF...ABR...
STATUS REPORT FOR WS 570
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
NDC003-043-045-047-073-081-093-120600-
ND
. NORTH DAKOTA COUNTIES INCLUDED ARE
BARNES KIDDER LAMOURE
LOGAN RANSOM SARGENT
STUTSMAN
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
MD 1946 CONCERNING SEVERE POTENTIAL...SEVERE THUNDERSTORM WATCH LIKELY 572... FOR PARTS OF NORTHEAST THROUGH EAST CENTRAL NEBRASKA
Mesoscale Discussion 1946
NWS Storm Prediction Center Norman OK
0135 AM CDT Wed Aug 12 2026
Areas affected...parts of northeast through east central Nebraska
Concerning...Severe potential...Severe Thunderstorm Watch likely
572...
Valid 120635Z - 120830Z
Probability of Watch Issuance...80 percent
SUMMARY...Ongoing developing severe storm cluster will probably be
maintained at least a few more hours, and its possible it could
approach areas near/west of Greater Omaha by 5-6 AM CDT, accompanied
by the risk for damaging wind gusts.
DISCUSSION...Though embedded within modest westerly deep-layer mean
flow on the order of 20 kt, the ongoing intense supercell/compact
cluster has been maintaining a southeastward propagation near 40
kts. This has been accompanied by an increase in severe gusts to
the north/northwest of Ainsworth and O'Neill. On its current track,
it appears likely to approach areas near/west of the Greater Omaha
vicinity by 10-11Z.
While there does appear potential to maintain continuing inflow of
seasonably moist air supportive of sizable CAPE, convection
continues to propagate into an environment with increased mid-level
inhibition, with somewhat limited forcing for ascent. Activity will
probably have to continue to grow upscale in the near term,
accompanied by a substantively expanding and strengthening surface
cold pool to provide continuing support for maintenance. This
remains a bit uncertain, but appears possible. Regardless, a risk
for severe winds will likely persist for at least a few more hours,
requiring a new severe weather watch issuance.
..Kerr/Smith.. 08/12/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...FSD...OAX...GID...LBF...
LAT...LON 43099897 42959838 42439688 42089601 41189634 41169742
41459838 42129968 42519984 42789958 43099897
MOST PROBABLE PEAK WIND GUST...65-80 MPH
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN
MD 1945 CONCERNING SEVERE THUNDERSTORM WATCH 572... FOR NORTHERN NE AND SOUTHERN SD
Mesoscale Discussion 1945
NWS Storm Prediction Center Norman OK
0102 AM CDT Wed Aug 12 2026
Areas affected...northern NE and southern SD
Concerning...Severe Thunderstorm Watch 572...
Valid 120602Z - 120730Z
The severe weather threat for Severe Thunderstorm Watch 572
continues.
SUMMARY...A maturing bow will continue to yield a risk for
higher-end wind potential over the next 1-2 hours as it moves into
northern portions of NE.
DISCUSSION...Latest radar imagery from KFSD/KUDX shows a potent
cluster evolving into a maturing bow along the NE/SD border with
echo tops increasing in the past 30 minutes to 60 kft. The airmass
remains very unstable per RAP forecast soundings (around 4000 J/kg
MUCAPE) with modest lower to mid-level flow (20-25 kt) increasing to
60 kt around 250 mb. This thermodynamic/kinematic environment will
continue to strongly favor severe gusts and a continuation of the
mature phase of the bow echo through at least 2-3am CDT. Recently
measured gusts in the 90-95 mph range in southern SD are indicative
of the higher-end wind potential.
..Smith.. 08/12/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...FSD...ABR...LBF...UNR...
LAT...LON 43620019 43529937 43109832 42619832 42279885 42359984
42770085 42950091 43180038 43620019
MOST PROBABLE PEAK WIND GUST...85-100 MPH
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1214 AM CDT Wed Aug 12 2026
Valid 121200Z - 131200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE
NORTHERN/CENTRAL PLAINS TO THE LOWER OHIO VALLEY...
...SUMMARY...
Thunderstorms with severe gusts and hail will be possible this
afternoon and evening across parts of the central and northern High
Plains. Damaging gusts and isolated hail will also be possible
across parts of the Midwest and Ohio Valley.
...IA to OH Valley...
One or more MCSs migrating through enhanced northwesterly flow aloft
amid a very moist and unstable airmass is possible again today
across the Midwest toward TN. Most forecast guidance suggests an MCS
or thunderstorm clusters could be ongoing over IA at the start of
the period (12z), with warm advection storms arcing across parts of
IL/IN. The early day warm advection storms could develop southeast
across the OH Valley, while the IA MCS develop southeast across the
Mid-MS/Lower OH Valley through afternoon. The exact evolution of
convection that is not yet apparent is uncertain, and how outflow
may influence how this activity evolves through the afternoon.
Regardless, the overall environmental parameter space will be
favorable for a damaging wind and isolated hail risk through early
evening.
...Northern/Central Plains...
East/southeasterly low-level flow will maintain modest moisture
across the Dakotas, increasing with southward extent across NE into
northern KS. Near-60 F dewpoints will likely spread westward into
eastern CO/WY/MT. Modest moisture beneath steep midlevel lapse rates
and 30+ kt effective shear magnitudes will support scattered
thunderstorm development across the High Plains. Initial cells will
pose a large hail and damaging wind risk. It is unclear how
convection will evolve with eastward extent across the region as
outflow from prior convection may largely limit stronger
destabilization. A developing low-level jet during the nighttime
hours will be focused across the southern Plains toward KS/southern
NE. This could support some upscale growth potential, but confidence
is low.
...Lower MI into NY/PA/NJ...
A belt of stronger northwesterly flow aloft will extend from Lower
MI into NY/PA today. A seasonally moist/unstable airmass will be in
place. Vertically veering wind profiles will foster 35+ kt effective
shear magnitudes, while hodographs are fairly elongated. Midlevel
lapse rates will remain modest, with MLCAPE around 1000-1500 J/kg
expected. Isolated to widely scattered storms will pose a risk for
damaging gusts and small hail.
...TN Valley/Southeast...
Thunderstorms are expected to develop by midday within a very moist
and strongly unstable airmass. Deep-layer northwesterly flow will
remain weak, but steep low-level lapse rates and PW values near 2
inches could support isolated wet microbursts with stronger
multi-cell clusters.
..Leitman/Moore.. 08/12/2026
SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
0100 AM CDT Wed Aug 12 2026
Valid 131200Z - 141200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR THE COLORADO
FRONT RANGE AND CENTRAL HIGH PLAINS EASTWARD INTO PARTS OF THE
MIDWEST AND OHIO VALLEY...
...SUMMARY...
Isolated severe storms are possible on Thursday from the Colorado
Front Range and central High Plains into the Ohio Valley.
...Synopsis...
Some amplification of the upper-level pattern is expected on
Thursday across the central/eastern CONUS. An upper ridge initially
over the lower MS Valley is forecast to expand and build northward
into parts of the Great Plains. To the east of building ridge, a
seasonably strong mid/upper-level shortwave trough is forecast to
move southeastward across the Great Lakes towards the Northeast. A
surface low is forecast to remain in place across the south-central
Plains. A nearly stationary front is forecast to extend
east-northeast of the low toward the lower MO Valley, and then
east-southeastward toward the lower OH Valley.
...Central Plains into parts of the Midwest/Ohio Valley...
Isolated severe potential remains evident in the vicinity of the
surface front on Thursday, though confidence in the details remains
low. Elevated convection and possibly a remnant MCS may be ongoing
at the start of the period from eastern NE into parts of IA/northern
MO. Depending on the extent to which the early-day convection can
propagate within the rich moisture and moderate to strong buoyancy
along the frontal zone, some severe threat could spread
east-southeastward toward the lower OH Valley through the day.
Otherwise, isolated storms may develop near/north of the front
through the day, with an increase in coverage expected Thursday
evening within a warm-advection regime. Generally modest and
front-parallel mid/upper-level flow may lead to training storms and
a tendency for convection to be undercut or generally remain
somewhat elevated. However, deep-layer shear will still be modestly
supportive of organized convection within the moist and unstable
environment, with some potential for isolated damaging gusts and
hail.
...CO Front Range into the adjacent High Plains...
To the north/northwest of the primary surface low, moist easterly
low-level flow will support moderate to locally strong
destabilization from the CO Front Range into parts of the central
High Plains. Deep-layer flow will generally remain modest, but
veering wind profiles will provide sufficient effective shear for
some storm organization. Isolated hail and locally severe gusts will
be possible with the strongest storms in this region.
Isolated to widely scattered storms will also be possible within the
hot and well-mixed regime near/south of the front and surface low.
Weak deep-layer shear should limit storm organization in this
regime, but steep low-level lapse rates could support localized
severe gusts.
...Northeast...
Seasonably strong mid/upper-level flow will overspread the Northeast
on Thursday. However, low-level flow will remain rather weak, and
generally modest moisture and lapse rates will limit
destabilization. MLCAPE Of 500-1000 J/kg will support development of
widely scattered thunderstorms across northern New England. There
will be some displacement between the strongest deep-layer flow and
more favorable buoyancy. Small hail and gusty winds could accompany
the strongest storms, but confidence in sufficient destabilization
remains too low for severe probabilities at this time.
...Southeast...
Thunderstorm development is expected across parts of AL/GA/SC on
Thursday, within a very warm and moist environment. Guidance varies
regarding the extent to which early-day convection and related
outflow move into the region from the north, and the influence any
such convection/outflow would have on storm development and
evolution later in the day. In general, deep-layer flow/shear will
be weak, but the very warm and moist environment could support
localized downburst potential. Confidence in an organized severe
threat is currently low, but if trends support the presence of any
outflow boundaries or remnant MCVs emanating from upstream, then
wind probabilities may eventually be needed for some part of this
region.
...Great Basin...
Storm development is again expected across parts of the Great Basin
on Thursday afternoon, with coverage potentially aided by a midlevel
trough approaching the region from central/southern CA. Deep-layer
shear will remain modest at best, but favorable lapse rates and
cooling temperatures aloft could support relatively vigorous
updrafts with potential for localized strong to severe gusts.
Uncertainty remains regarding the organization of any severe threat,
but wind probabilities may eventually be needed for this area as
well.
..Dean.. 08/12/2026
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1251 AM CDT Wed Aug 12 2026
Valid 121200Z - 131200Z
...Synopsis...
A mid-level trough will pivot into the Pacific Northwest today as a
broader ridge over much of the West begins to shift eastward.
Moisture advection from the Pacific, falling H500 heights and
subsequent increasing instability will promote thunderstorm
development across northern WA, the ID Panhandle and northwestern MT
this afternoon and evening. Dry and breezy conditions between the
Pacific Northwest trough and more expansive monsoon moisture across
the southern Intermountain West will promote elevated fire weather
concerns across portions of northeastern CA, northwestern NV and the
Upper Snake River Plain. A deepening surface low across central KS
will result in enhanced southerly winds across the Southern Plains
this afternoon. Elevated fire weather concerns remain for portions
of the TX/OK Panhandles, northwestern OK and adjacent portions of
KS/CO.
...Southern Plains...
Enhanced southerly winds within a well mixed boundary layer south of
the surface low across KS will evolve late this morning into the
afternoon. South winds of around 15 mph (locally 20 mph at times)
and low relative humidity during peak heating will promote elevated
fire weather concerns across the southern High Plains. Above normal
temperatures in the lower 100s F will contribute to low afternoon
RH, with increasingly dry conditions farther west across
southeastern CO and eastern NM where RH below 10 percent is
possible. Fuels continue to dry, with ERC values climbing into the
97-99th percentiles under multiple days of triple digit heat and dry
conditions, curing fine fuels. Existing elevated highlights were
shifted slightly westward given latest model/ensemble guidance.
...Northeastern Washington, Idaho Panhandle and Northwestern
Montana...
Showers and thunderstorms are expected to initially develop over
more complex terrain of northern WA, ID Panhandle and northwestern
MT this afternoon as a mid-level trough enters the Pacific
Northwest. Wetting rains are possible under heavier rain cores with
PWAT values nearing 1.00". However, fuels should remain receptive to
potential ignitions outside of these heavier cores. Latest CAM
guidance suggests some lingering thunderstorm potential into the
evening and overnight hours in the northern Columbia Basin, in
addition to increasing east-northeast storm trajectories as the
trough pushes farther into WA. This should limit rainfall
accumulations and support a dry lightning threat for portions of the
northern Columbia Basin where isolated dry thunderstorm highlights
have been extended.
...Northern Great Basin and Upper Snake River Plain of Idaho...
Dry and breezy conditions north of an advancing monsoon moisture
plume across the Southwest will bring elevated fire weather concerns
to northeastern CA, northwestern NV, far southern OR and the Upper
Snake River Plain in ID. West winds of around 15 mph combined with
RH locally below 10 percent amid very dry fuels will support an
elevated fire weather threat today. Elevated highlights were
extended eastward into north-central NV and adjacent OR/ID areas.
..Williams.. 08/12/2026
...Please see www.spc.noaa.gov/fire for graphic product...
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1252 AM CDT Wed Aug 12 2026
Valid 131200Z - 141200Z
...Synopsis...
Mid/upper troughing becomes established along the West Coast while
upper ridging edges eastward towards the Great Plains. An embedded
short wave translating northeastward into CA/NV will bring a few
high-based thunderstorms within a corridor of fringe monsoonal
moisture across portions of the northern Great Basin. Additional
thunderstorms associated with another embedded mid-level
perturbation will affect portions of the Northern Rockies.
...Southern Plains...
Persistent southerly winds south of a surface low across KS will
maintain a fire weather threat into D2/Thursday across portions of
the Southern Plains. South winds of up to 15 mph amid low RH and
exceptionally dry fuels will support a few hours of elevated fire
weather concerns for western OK and eastern TX Panhandle. A diffuse
convergence zone will stretch southwestward from the surface low
across KS. Sufficient mid-level moisture and instability atop a well
mixed and dry sub-cloud boundary layer near this boundary will
support afternoon convection across portions of the TX Panhandle,
northwestern OK and adjacent areas of southern KS Thursday
afternoon. Receptive fuels with ERC values in the 97-99th percentile
range and cured fine fuels could promote a few ignitions outside of
heavier rain cores from these initially high-based thunderstorms.
Downdraft CAPE of 1500 J/kg or greater will evolve as surface
temperatures climb into the lower 100s F yet again, increasing
potential for downburst winds impacting any potential ignitions/new
fire starts. Introduced isolated dry thunderstorm highlights to
cover this threat.
...Northern Great Basin and Northern Rockies...
A mid-level short wave will translate into the Great Basin Thursday,
interacting with more diffuse monsoon moisture where PWATs in the
0.6-0.9" range settle across the northern Great Basin. Isolated
high-based thunderstorms are expected to evolve Thursday afternoon
across northeastern CA into southeastern OR, far northwestern NV and
southwestern ID. New ignitions are possible outside more intense
rain cores with ERCs still in the 90-95th percentile. Another
mid-level wave will promote convection across portions of the
Northern Rockies. Northeastward storm trajectories up to 30 mph will
limit rainfall in some thunderstorms, increasing ignition potential
over dry fuels. Some modifications were made to these highlighted
areas based on latest model guidance but largely remain intact.
..Williams.. 08/12/2026
...Please see www.spc.noaa.gov/fire for graphic product...
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