No watches are valid as of Mon Sep 7 22:33:01 UTC 2026.MD 2266 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF SOUTHWESTERN NEBRASKA AND FAR NORTHWESTERN KANSAS
Mesoscale Discussion 2266
NWS Storm Prediction Center Norman OK
0530 PM CDT Mon Sep 07 2026
Areas affected...portions of southwestern Nebraska and far
northwestern Kansas
Concerning...Severe potential...Watch unlikely
Valid 072230Z - 080000Z
Probability of Watch Issuance...20 percent
SUMMARY...Isolated damaging/severe wind gusts and perhaps an
instance of marginally severe hail may occur with developing
thunderstorms over the next 1-2 hours.
DISCUSSION...Isolated thunderstorm development is ongoing along a
weak surface boundary/confluence zone across southwestern
NE/northwestern KS where latest objective analysis suggests MLCIN
has eroded. Latest surface observations within the inflow
environment show that temperatures are approaching 100 F, with
dewpoints in the low 60s F. Modifying the nearby 18z LBF observed
sounding for these conditions depicts a well-mixed boundary layer
with very steep low- and mid-level lapse rates and an MLLCL height
above 2.5 km. While available buoyancy remains somewhat modest
(1000-1500 J/kg MLCAPE), this thermodynamic environment is
supportive of efficient evaporative cooling, which may foster a risk
for isolated damaging/severe wind gusts. This activity is also
located along the southeastern periphery of stronger mid/upper-level
flow, but effective shear of around 30-35 kts and the aforementioned
steep mid-level lapse rates may be sufficient for an isolated
instance of marginally severe hail.
With the eventual onset of nocturnal cooling (and the indication
that some convective inhibition may remain within the downstream
environment), the temporal window for the severe risk may remain
rather brief. With the added expectation for this risk to remain
isolated, watch issuance is considered unlikely.
..Chalmers/Gleason.. 09/07/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...GID...LBF...GLD...
LAT...LON 40479954 40339959 39830016 39400131 39370192 39550211
39870204 40300170 41000067 41020056 41160008 41079966
40759952 40479954
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
MD 2265 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR WESTERN/CENTRAL NORTH DAKOTA
Mesoscale Discussion 2265
NWS Storm Prediction Center Norman OK
0353 PM CDT Mon Sep 07 2026
Areas affected...western/central North Dakota
Concerning...Severe potential...Watch possible
Valid 072053Z - 072300Z
Probability of Watch Issuance...40 percent
SUMMARY...A conditional severe threat may evolve this
afternoon/evening.
DISCUSSION...A cumulus field across northern/central North Dakota
has become increasingly agitated this afternoon, with attempts at
initiation. At least one tower has sustained with reflectively now
on radar. Air mass recovery has been ongoing through the afternoon
across this region after morning convection. Temperatures warmed
back into the 80s to 90s along and west of a pseudo dryline/cold
frontal boundary/surface low interface.
Forcing for ascent is overall weak, with the vorticity max upstream
across Montana for now, but will increase this evening with the
increasing low-level jet. The 18z RAOB from BIS sampled a moderately
unstable air mass with a clockwise turning hodograph and ample deep
layer shear. Conditionally, the moderately unstable and strongly
sheared environment would support supercells, capable of large hail,
damaging wind, and perhaps a tornado. Trends in CAM guidance through
the day for less and less convective signal lead to low confidence
in the overall scenario, but, it does appear that at least isolated
supercells may develop. This area will be monitored for watch
potential.
..Thornton/Hart.. 09/07/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...FGF...BIS...
LAT...LON 48970357 48390318 48000291 47590259 47030200 46630134
46500091 46610039 47119992 48019955 48689997 48830025
49040095 48970357
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0259 PM CDT Mon Sep 07 2026
Valid 072000Z - 081200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
CENTRAL NORTH DAKOTA AND SOUTHEAST SOUTH DAKOTA...
...SUMMARY...
Widely scattered severe storms capable of mainly large hail are
expected over portions of North Dakota as well as southeast South
Dakota into northeast Nebraska this afternoon into evening. Isolated
damaging wind potential will exist over the northern and central
Plains into the upper Mississippi Valley. Locally damaging wind
gusts remain possible this afternoon over the central Gulf Coast
states.
...20Z Update...
The MRGL Risk/5-percent wind area was expanded slightly
west-southwestward in parts of eastern MT. Here, a small
north/south-oriented line segment is tracking eastward into an
increasingly warm PBL. This activity will continue to pose a risk of
a few severe wind gusts this afternoon. See MCD #2264 for more
details. Elsewhere, very minimal changes were made with this update.
..Weinman.. 09/07/2026
.PREV DISCUSSION... /ISSUED 1112 AM CDT Mon Sep 07 2026/
...ND...
A fast-moving shortwave trough currently over WY/MT will track
northeastward into the Dakotas this afternoon. Strong
heating/mixing in southwest ND will lead to a sharpening dryline
across central ND by mid/late afternoon. This will be the likely
focus for thunderstorm development after 22z. Forecast soundings in
the warm-sector east of the dryline suggest sufficient low-level and
deep-layer shear for supercell storm-modes. Large hail and perhaps a
tornado or two are possible in the most intense storms. This
activity will spread eastward into northeast ND this evening before
weakening.
...CO/KS/NE/SD...
A weak surface boundary is present today from northeast CO into
central NE. Scattered afternoon thunderstorms will form over the
mountains of central CO, with development spreading eastward along
the boundary through the afternoon. Strong heating and a deeply
mixed boundary-layer will promote intense downdrafts in the
strongest cores. By early evening, activity may spread into
southeast SD where greater low-level moisture and CAPE will pose a
risk of a few more intense storms capable of hail or even a tornado.
Recent model solutions have been backing off on this SD scenario,
but will maintain the ongoing SLGT for now.
...LA/MS/AL...
Hot and humid conditions will prevail over the central Gulf coast
region today, with full sunshine and dewpoints in the low-mid 70s.
Steering flow is weak, but high CAPE and ample moisture suggest a
risk of occasional intense downdrafts in the strongest storms.
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1246 PM CDT Mon Sep 07 2026
Valid 081200Z - 091200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE CENTRAL
PLAINS TO THE UPPER MIDWEST...
...SUMMARY...
Strong to severe storms are possible on Tuesday from the central
Plains into the Upper Midwest.
...Central Plains to Upper Midwest...
An upper-level shortwave trough currently translating through the
northern Rockies will move into the Canadian Prairies and northern
Plains on Tuesday. A secondary upper-level feature will translate
from the northern Rockies to the northern Plains through the period.
South of these features, enhanced mid-to upper-level southwesterly
flow will overspread the Mid-Missouri and Upper Mississippi Valleys.
At the surface, a low over Manitoba will lift northeastward into
Ontario by early Wednesday. A trailing cold front will move eastward
across the Upper Midwest while the southern extent of the boundary
is forecast to stall over southern Nebraska.
Ahead of the front, persistent southerly return flow will maintain a
moist warm-sector with weak to moderate instability ahead of the
front. Most CAM guidance depicts elevated thunderstorms Tuesday
morning across parts of Minnesota and Wisconsin, near the nose of
the low-level jet. This early activity will likely pose an initial
risk for marginally severe hail and isolated strong wind gusts.
Further south, severe potential is expected to gradually increase
during the evening ahead of the front across Iowa, eastern Nebraska,
and potentially northern Kansas. Deep-layer shear will progressively
lessen with southward extent but strong convergence along the
stalling boundary should support convective initiation within the
moderately unstable boundary-layer. Initial cells will likely have a
threat for isolated large hail and strong wind gusts, but are
expected to quickly grow upscale into line segments with a greater
damaging wind threat later Tuesday evening.
..Bentley.. 09/07/2026
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