RSS Mesoscale Discussions from Storm Prediction Center
No watches are valid as of Thu Jun 4 06:05:02 UTC 2026.
No Mesoscale Discussions are in effect as of Thu Jun 4 06:05:03 UTC 2026.
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0100 AM CDT Thu Jun 04 2026
Valid 041200Z - 051200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS 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.
...Synopsis...
Broadly zonal mid-level flow across the northern CONUS will persist
on Thursday, with a subtropical ridge located across the northern
Gulf. Additionally, a weak mid-level vorticity maximum/short-wave
trough across the southern/central Plains will continue to
weaken/open and begin merging into the main belt of westerlies
across the north-central US.
At the surface, a weak surface low will develop during the day
across the central High Plains. This low will move south and east
into north-central Kansas/south-central Nebraska overnight.
... Portions of the Northern Plains ...
Embedded within the broadly zonal flow are several subtle short-wave
troughs. One of these troughs will move from the northern Rockies
across the northern Plains. Ahead of this feature, moderate
instability will develop, with surface-based CAPE between 1500-2000
J/kg likely. As weak height falls overspread the region, a surface
low across eastern Wyoming will move south and east into northeast
Colorado and eventually into the central Plains. To the north of
this low, easterly/southeasterly upslope flow and increasing
large-scale ascent will combine for thunderstorms to develop during
the afternoon. Supercells will be possible as the southeasterly
surface winds and westerly mid-level flow results in 40-50 knots of
vertical shear. Steep mid-level lapse rates will support large to
very large hail and the potential for damaging thunderstorm winds. A
tornado or two will be possible with any storm that can interact
with the synoptic front.
Another area for storms will likely occur farther east, across
eastern South Dakota along a residual/slow-moving cold front.
Moderate instability and weak-to-moderate shear will support some
thunderstorm organization. Large hail will be possible with initial
development, with a tendency for storms to grow upscale and
transition to a damaging wind threat.
... Central Kansas northeast into Central Iowa...
A remnant MCV/sub-synoptic low/mid-level trough located across the
Southern Plains this morning will slowly lift north/northeast across
the Central Plains during the day. Ahead of this feature, surface
dewpoints will rise into the upper-60Fs to low-70Fs, resulting.
Diurnal heating should result in increasing instability during the
day, as suggested by the HREF mean surface-based CAPE reaching
between 1000-1500 J/kg and localized areas approaching 2000-2500
J/kg.
With several days of convection upstream of northeast Kansas into
southwest Iowa in the elevated mixed layer source region, forecast
soundings across the region reflect a largely uncapped environment
during the afternoon. The result should be multiple areas/rounds of
convective development during the afternoon and evening hours. The
moist environment and potential for moderate instability will result
in a potential for strong thunderstorm winds and marginally severe
hail. Additionally, forecast guidance shows an increasing low-level
mass field response during the evening hours, resulting in
increasing low-level curvature/shear. Thus, a tornado threat may
materialize during the late afternoon/evening hours, especially with
any thunderstorms that can remain discrete.
..Marsh/Moore.. 06/04/2026
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SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1221 AM CDT Thu Jun 04 2026
Valid 051200Z - 061200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS CENTRAL AND
EASTERN NEBRASKA...NORTHERN KANSAS... MUCH OF IA...INTO SOUTHERN
MINNESOTA AND SOUTHWEST WISCONSIN...
...SUMMARY...
Scattered severe storms capable of large to very large hail,
damaging winds with potentially significant gusts, and perhaps a
couple of tornadoes are expected Friday afternoon into night across
portions of the central Plains into upper Great Lakes.
...Synopsis...
A series of weak, mid-level disturbances will translate from the
northern Plains into the upper Great Lakes, ahead of a building
ridge from central Canada into the northern Plains. At the surface,
the primary focus for strong to severe thunderstorm development is a
front, which is expected to stretch from the western UP of MI
southwest through the mid MO Valley into the central High Plains by
mid-afternoon Friday. A surface low is forecast to develop along the
front over south-central NE or north-central KS, with a dryline
extending south-southwest from that feature into northwest OK.
...Central Plains into the Upper Great Lakes...
Latest guidance is suggestive that the combination of steep
mid-level lapse rates and boundary-layer dewpoints in the upper 60s
to low 70s will support strong instability along and south of the
NE/IA segment of the front with HREF mean SBCAPE as high as
3000-4000+ J/kg. Forecast instability decreases with northeastward
extent into the upper Midwest, due in part to the potential for
early-day storms and lingering cloud cover.
While mid-level heights are forecast to rise through the day across
the central Plains, strong heating west of the dryline and south of
the surface front should sufficiently erode the cap for isolated to
widely scattered thunderstorm development by late afternoon into
early evening in the vicinity of the triple point over south-central
NE. Locally backed near-surface winds in that area will offset
somewhat marginal mid-level flow to yield 30-35 kt of deep-layer
shear, which will support supercell storm modes, given the degree of
instability. Large to very large hail and perhaps a couple tornadoes
will be possible in the early life cycle of the storms, with a
subsequent transition to more of a damaging wind threat (with
significant gusts possible) by mid/late evening.
Additional severe storms are expected farther east along the front
into IA during the afternoon and evening hours with strong
instability and modest vertical shear supporting a threat for large
to very large hail and severe wind gusts.
Should subsequent model guidance show higher confidence in more
concentrated storm development along the NE/IA segment of the front,
an upgrade to a level 3/Enhanced Risk may be considered.
Farther northeast along the front across the upper Midwest, the
diffuse nature of the boundary casts some uncertainty on exactly
where the favored area for diurnally enhanced storm development will
be. Nonetheless, the presence of a moderately unstable air mass and
modest deep-layer shear will be supportive of a few severe storms
capable of large hail and damaging wind gusts. An isolated
severe-weather threat may continue to spread east into the upper
Great Lakes Friday evening into night, driven largely by warm
advection along a westerly low-level jet.
..Mead.. 06/04/2026
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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1127 PM CDT Wed Jun 03 2026
Valid 041200Z - 051200Z
...Synopsis...
Ahead of a slow approaching deep upper low currently offshore the
British Columbia Coast, zonal flow will overspread the Northwest
through the Upper Midwest. Multiple embedded perturbations within
the downstream flow will encourage additional precipitation across
portions of Minnesota and Wisconsin, bringing some relief to a
recently receptive fuelscape. Upper ridging will continue to flatten
over the Great Lakes region, steering surface high pressure atop the
Southeast and initiating a gradual warming trend into the weekend.
A weak, dry cold front will stall across the Great Basin today,
extending from southwestern Wyoming into central Nevada. Behind the
front, sustained westerly winds of 10-20 mph (gusts up to 35 mph in
the upper Colorado Western Slope into the Wyoming Basin) are
expected through much of the afternoon hours. Hot and very dry
(5-15% minimum RHs) conditions supportive of deep boundary layer
mixing up to 450 mb will be in place over much of the Southwest,
Great Basin, and central Rocky Mountain regions. Elevated fire
weather highlights have been maintained where this combination of
wind/RH amid receptive fuel conditions will support a limited fire
weather risk this afternoon. Given the right alignment of wind, RH,
and very dry fuels possible within localized portions of the drawn
area, critical thresholds could be briefly achieved.
..Elizalde-Garcia.. 06/04/2026
...Please see www.spc.noaa.gov/fire for graphic product...
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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1129 PM CDT Wed Jun 03 2026
Valid 051200Z - 061200Z
...Synopsis...
A robust upper-level trough will approach the Northwest Coast on Day
2/Friday, increasing mid-level southwesterly flow across the Great
Basin. Weaker deep-layer flow will persist over the Southwest where
a very dry airmass exists. Several perturbations embedded within
zonal flow across the northern Plains and Upper Midwest will
continue chances for precipitation, meanwhile surface high pressure
over the Southeast will promote dry conditions and above normal
temperatures.
A warm and dry airmass will linger into Day 2/Friday across the
Great Basin and Southwest. Latest guidance depicts weaker flow aloft
portions of the Southwest, however, very low daytime RH near 10%
(localized single digits) amid 10-20 mph terrain-driven winds will
support a fire weather threat across northwest Arizona, southeastern
Nevada, and southwestern Utah. Elevated highlights have been
introduced where aforesaid weather conditions will overlap a region
of receptive fuels (broad 80-90th percentile ERCs).
..Elizalde-Garcia.. 06/04/2026
...Please see www.spc.noaa.gov/fire for graphic product...
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