No watches are valid as of Thu Jun 4 20:01:02 UTC 2026.MD 0979 CONCERNING SEVERE POTENTIAL...SEVERE THUNDERSTORM WATCH LIKELY FOR PORTIONS THE SOUTHEASTERN MONTANA INTO THE BLACK HILLS
Mesoscale Discussion 0979
NWS Storm Prediction Center Norman OK
0232 PM CDT Thu Jun 04 2026
Areas affected...portions the southeastern Montana into the Black
Hills
Concerning...Severe potential...Severe Thunderstorm Watch likely
Valid 041932Z - 042100Z
Probability of Watch Issuance...80 percent
SUMMARY...Scattered strong to severe thunderstorms will develop
eastward through the afternoon, with large to very large hail and
strong/severe wind gusts the main hazards. A Severe Thunderstorm
Watch will likely be needed for a portion of the discussion area.
DISCUSSION...Moist, southeasterly flow north of a quasi-stationary
surface boundary and continued surface heating are contributing to
steepening low-level lapse rates and eroding MLCIN across portions
of the northern High Plains as of early this afternoon. Coupled with
increasing ascent ahead of an approaching mid-level shortwave
trough, this is promoting gradual thunderstorm development across
southeastern Montana and northeastern Wyoming, with deepening
cumulus also noted along portions of the Black Hills. As this
activity evolves eastward through the afternoon, two different
regimes of severe potential appear likely.
In the Black Hills vicinity, western/central South Dakota, and
northwestern Nebraska along and north of the surface boundary,
modestly strong westerly flow aloft (35-40 kts sampled at 4-5 km AGL
by the BLX/RIW VAD profiles) and effective shear of 35-45 kts are
likely to overlap greater low-level moisture and moderate buoyancy
(MLCAPE around 1000-2000 J/kg), with occasional supercells possible.
Coupled with steep mid-level lapse rates (700-500 mb lapse rate of
8.7 C/km sampled by the 18z UNR observed sounding) and elongated
hodographs, this should support large to very large hail as the
primary threat. Meanwhile, latest guidance and objective analysis
depicts marginally weaker effective shear (around 25-35 kts) and
steeper low-level lapse rates farther to the north across portions
of eastern Montana into southwestern South Dakota. This would favor
upscale growth along developing cold pools, with a more
multicellular storm mode and greater risk for strong to severe wind
gusts.
Trends will continue to be monitored, and watch issuance will likely
be needed for a portion of the discussion area to cover these
threats.
..Chalmers/Mosier.. 06/04/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...BIS...LBF...UNR...CYS...BYZ...GGW...
LAT...LON 44050566 44700590 45420596 46080589 46630550 46990469
47200376 47120307 46960267 46600228 46110206 44910200
43990199 43250200 42870201 42590212 42320225 42180243
42150271 42170310 42220361 42500419 43150505 44050566
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN
MD 0978 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PARTS OF NORTHEAST KANSAS INTO SOUTHEAST NEBRASKA AND VICINITY
Mesoscale Discussion 0978
NWS Storm Prediction Center Norman OK
0129 PM CDT Thu Jun 04 2026
Areas affected...parts of northeast Kansas into southeast Nebraska
and vicinity
Concerning...Severe potential...Watch unlikely
Valid 041829Z - 042130Z
Probability of Watch Issuance...20 percent
SUMMARY...A few strong to severe storms are possible from northern
Kansas into southwest Iowa late this afternoon. Locally damaging
gusts or a brief/weak tornado cannot be ruled out.
DISCUSSION...Satellite imagery shows an MCV over north-central KS
and into south-central NE, while surface obs show a weak low near
Russell KS. East of this feature, a leading outflow extends from
just west of the NE/IA border southwestward toward the surface low.
A warming air mass with southerly winds and upper 60s F dewpoints is
aiding the development of thunderstorms near the boundary in
southeast NE and trailing into north-central KS. The 18Z OAX and TOP
soundings show high PWAT but poor lapse rates overall and lightly
veering winds with height.
As heating continues, the zone ahead of the MCV should continue to
see increased storm coverage and intensity. Low-level shear near the
modifying outflow and ahead of the MCV may increase later today,
possibly supporting isolated supercells. While deep-layer shear is
marginal, the very moist air mass combined with locally stronger 0-1
SRH may support a brief/weak tornado or two. Otherwise, marginal
hail or localized damaging gusts may occur.
..Jewell/Mosier.. 06/04/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...DMX...EAX...OAX...TOP...ICT...GID...
LAT...LON 39749857 40039715 40429643 40859585 41649517 41729465
41269450 40229495 39749527 39369567 39059639 38959731
39079801 39249841 39529869 39749857
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1128 AM CDT Thu Jun 04 2026
Valid 041630Z - 051200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND
EVENING OVER PORTIONS OF THE NORTHERN PLAINS...
...SUMMARY...
Severe thunderstorms capable of large to very large hail and
damaging winds are possible today from parts of the northern High
Plains across northern Nebraska and much of South Dakota. More
isolated occurrences of large hail and damaging winds appear
possible farther south across portions of the central Plains.
...Southeast MT through the Dakotas into southern MN...
Morning surface analysis places a weakening cold front from
northwest MN through south-central SD to a weak low near the
WY/SD/NE border intersection. Western portion of this boundary (from
central SD westward) is forecast to stall, with perhaps some retreat
northward during the late afternoon, while the eastern portion over
MN progresses slowly eastward. Dewpoints will likely stay in the 60s
along this boundary, with moderate to strong buoyancy developing by
late afternoon. Moisture convergence, augmented by modest
large-scale ascent attendant to a shortwave moving across MT, will
likely result in scattered convective initiation by the late
afternoon. Additional storms are expected farther west across
eastern MT ahead of the aforementioned shortwave. Moderate
deep-layer shear will support occasional supercells, with large to
isolated very large hail as the primary risk. Storms will spread
into the central Dakotas through the evening with a continued severe
threat.
Farther east, late afternoon thunderstorm development is expected
along the cold front. Deep-layer shear will be weaker than areas
farther west, and a more outflow-dominant storm mode appears likely.
Isolated hail is still possible early in the convective cycle,
particularly into central SD where steeper mid-level lapse are
expected.
...Central/Eastern KS into southeast NE/northwest MO/western IA...
Morning satellite imagery shows a well-defined MCV over western KS,
with widespread cloud cover throughout its eastern periphery from
central KS across south-central and eastern NE. Surface observations
show dewpoints in the mid 60s beneath this cloud cover, with
temperatures ranging from the upper 60s across central KS to the mid
70s across southwest IA. Southerly flow is anticipated throughout
the day today, maintaining low-level moisture advection within this
corridor. This increasing moisture coupled with sheltered/cloudy
conditions will likely result in dewpoints climbing into the upper
60s (perhaps even some low 70s) across this region by the late
afternoon. Modest heating is anticipated as well, with temperatures
likely in the mid 70s to low 80s. Mid-level lapse rates are poor
(generally less than 6 deg C per km from 700 to 500 mb), but the
ample low-level moisture will still support afternoon/late afternoon
MLCAPE around 1500 to 2000 J/kg and little, if any, convective
inhibition.
Ascent attendant to the MCV and low-level convergence throughout its
eastern periphery will support widespread thunderstorm development
within this unstable and uncapped environment. Deep-layer shear will
be weak (less than 25 kt from 0-6 km) across much of the region,
with a largely multicellular mode anticipated. That being said, an
increase in low-level southerly flow is expected throughout the
eastern periphery of the MCV, contributing to some moderate
lengthening of the low-level hodograph. This stronger low-level
southerly flow combined with the ample moisture in place (i.e. PW
values approaching 1.8" by the late afternoon, which is above the
90th percentile at TOP) results in a unique environment supportive
of brief tornadoes. Even so, the lack of stronger deep-layer shear
still suggests a predominantly disorganized storm mode, which should
keep any tornado threat isolated enough to keep probabilities at 2%.
A few water-loaded downbursts are possible as well.
..Mosier/Chalmers.. 06/04/2026
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0248 PM CDT Thu Jun 04 2026
Valid 042000Z - 051200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF
THE NORTHERN PLAINS...
...SUMMARY...
Severe thunderstorms capable of large to very large hail and
damaging winds are still possible today from parts of the northern
High Plains across northern Nebraska and much of South Dakota. More
isolated occurrences of large hail and damaging winds appear
possible farther south across portions of the central and southern
Plains.
...20Z Update...
The previous forecast (see below) remains largely on track. The
primary change made to the outlook was to expand 5 percent severe
wind probabilities into portions of the southern Plains. A couple of
measured severe gusts were noted in the TX Panhandle over the past
two hours. Given ample heating/buoyancy preceding thunderstorms from
northern OK to the eastern TX Panhandle, the occurrence of a few
more severe gusts is plausible.
..Squitieri.. 06/04/2026
.PREV DISCUSSION... /ISSUED 1128 AM CDT Thu Jun 04 2026/
...Southeast MT through the Dakotas into southern MN...
Morning surface analysis places a weakening cold front from
northwest MN through south-central SD to a weak low near the
WY/SD/NE border intersection. Western portion of this boundary (from
central SD westward) is forecast to stall, with perhaps some retreat
northward during the late afternoon, while the eastern portion over
MN progresses slowly eastward. Dewpoints will likely stay in the 60s
along this boundary, with moderate to strong buoyancy developing by
late afternoon. Moisture convergence, augmented by modest
large-scale ascent attendant to a shortwave moving across MT, will
likely result in scattered convective initiation by the late
afternoon. Additional storms are expected farther west across
eastern MT ahead of the aforementioned shortwave. Moderate
deep-layer shear will support occasional supercells, with large to
isolated very large hail as the primary risk. Storms will spread
into the central Dakotas through the evening with a continued severe
threat.
Farther east, late afternoon thunderstorm development is expected
along the cold front. Deep-layer shear will be weaker than areas
farther west, and a more outflow-dominant storm mode appears likely.
Isolated hail is still possible early in the convective cycle,
particularly into central SD where steeper mid-level lapse are
expected.
...Central/Eastern KS into southeast NE/northwest MO/western IA...
Morning satellite imagery shows a well-defined MCV over western KS,
with widespread cloud cover throughout its eastern periphery from
central KS across south-central and eastern NE. Surface observations
show dewpoints in the mid 60s beneath this cloud cover, with
temperatures ranging from the upper 60s across central KS to the mid
70s across southwest IA. Southerly flow is anticipated throughout
the day today, maintaining low-level moisture advection within this
corridor. This increasing moisture coupled with sheltered/cloudy
conditions will likely result in dewpoints climbing into the upper
60s (perhaps even some low 70s) across this region by the late
afternoon. Modest heating is anticipated as well, with temperatures
likely in the mid 70s to low 80s. Mid-level lapse rates are poor
(generally less than 6 deg C per km from 700 to 500 mb), but the
ample low-level moisture will still support afternoon/late afternoon
MLCAPE around 1500 to 2000 J/kg and little, if any, convective
inhibition.
Ascent attendant to the MCV and low-level convergence throughout its
eastern periphery will support widespread thunderstorm development
within this unstable and uncapped environment. Deep-layer shear will
be weak (less than 25 kt from 0-6 km) across much of the region,
with a largely multicellular mode anticipated. That being said, an
increase in low-level southerly flow is expected throughout the
eastern periphery of the MCV, contributing to some moderate
lengthening of the low-level hodograph. This stronger low-level
southerly flow combined with the ample moisture in place (i.e. PW
values approaching 1.8" by the late afternoon, which is above the
90th percentile at TOP) results in a unique environment supportive
of brief tornadoes. Even so, the lack of stronger deep-layer shear
still suggests a predominantly disorganized storm mode, which should
keep any tornado threat isolated enough to keep probabilities at 2%.
A few water-loaded downbursts are possible as well.
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