No watches are valid as of Sun Apr 12 23:02:02 UTC 2026.MD 0393 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR NORTHEAST MINNESOTA
Mesoscale Discussion 0393
NWS Storm Prediction Center Norman OK
0600 PM CDT Sun Apr 12 2026
Areas affected...Northeast Minnesota
Concerning...Severe potential...Watch unlikely
Valid 122300Z - 130000Z
Probability of Watch Issuance...20 percent
SUMMARY...A small window for large hail, wind damage and possibly a
brief tornado, before storms cross over into the cool air and
weaken.
DISCUSSION...A small cluster of storms has intensified gradually
near the surface triple point to the northwest of Duluth. This
cluster is located along the northwest edge of the remaining
warm/moist sector, and immediately west of slow-moving lake breeze.
There will be a narrow window where the environment will support
supercells with a low risk of all hazards, but the threat will be
constrained to large hail once the storm becomes elevated to the
cool side of the lake breeze. Given the small area in time and
space, a watch does not appear necessary.
..Thompson/Hart.. 04/12/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...DLH...
LAT...LON 47129163 46979220 46999258 47199271 47319262 47489250
47579214 47659173 47539146 47319142 47129163
MOST PROBABLE PEAK TORNADO INTENSITY...85-115 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
0256 PM CDT Sun Apr 12 2026
Valid 122000Z - 131200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
CENTRAL TEXAS...
...SUMMARY...
Isolated to scattered severe thunderstorms remain possible today
into evening mainly across parts of Texas and perhaps other nearby
parts of the southern Plains. More isolated severe storms may occur
across portions of the Upper Great Lakes and northern Rockies.
...20z Update Central TX...
Filtered diurnal heating in the wake of earlier showers and storms
across much of central TX was supporting moderate destabilization
this afternoon. While mid-level lapse rates are generally poor,
sufficient destabilization should support a gradual uptick in
convective coverage this afternoon and evening. With moderate
deep-layer shear in place, some organization could support a risk
for damaging gusts, hail, and tornado or two.
...MN/WI...
The aforementioned warm front continues to surge north but has
slowed farther south than earlier guidance. Weak to moderate
destabilization along and just south of the boundary will remain
supportive of a conditions supercell risk this afternoon/evening.
Strong shear profiles east of the surface low and near the rapidly
modifying boundary could support a risk for hail and possibly a
tornado. Have shifted severe probabilities southward slightly to
better match the observed frontal positioning. See MCD #390 for the
latest information.
...OK/KS/TX Panhandle...
A conditional risk for a supercell or two remains evident this
afternoon across the dryline in the central and southern Plains.
Ample heating in the wake of an early morning MCS could allow for
isolated storm this afternoon or evening as the dryline is forecast
to mix eastward before eventually retreating. Forecast guidance
continues to show weak subsidence suppressing convective
development, but deepening cumulus evident over the southern TX
Panhandle could support an isolated storm this evening. All severe
hazards would be possible.
...Intermountain West...
Steep mid-level lapse rates beneath the cold core of the upper low
over the West will continue to support scattered high-based storms
this afternoon. With a relatively dry-sub cloud layer, somewhat deep
boundary-layer mixing will support strong to
severe downburst winds.
..Lyons.. 04/12/2026
.PREV DISCUSSION... /ISSUED 1129 AM CDT Sun Apr 12 2026/
...Synopsis...
Recent satellite imagery shows a pair of phased shortwave troughs
over the Plains, one moving through the Dakotas and another moving
through KS/OK. Both of these waves are forecast to continue
northeastward through the day, with the northern wave reaching
northwestern Ontario and the southern wave reaching the Great Lakes
region. This evolution will take these waves east/northeast of the
higher low-level moisture, which will remain in a corridor from the
southern Plains northeastward into the Upper Midwest. Showers and
thunderstorms are anticipated throughout much of this corridor
today, with highest thunderstorm chances across central/east TX and
from the Upper Midwest into the Great Lakes.
Farther west, an upper low is slowly drifting eastward across
northern CA. Guidance suggests this eastward drift will continue
today, with several shortwave troughs rotating quickly through the
base of this system and ejecting across the Great Basin and northern
Rockies. Large-scale ascent and modest mid-level moisture associated
with these waves will combine with cold temperatures aloft and
associated buoyancy to support thunderstorms today from northern CA
across the northern Great Basin and northern Rockies, and into the
northern Plains.
...Southern/Central Plains...
Much of this region will be displaced south and west of any notable
large-scale forcing for ascent. This limited ascent, combined with
the showers and isolated thunderstorms currently ongoing across
central and east TX, complicates the overall forecast today, with
mesoscale factors likely contributing significantly to when and
where storms develop this afternoon and evening. General expectation
is for development along the southern and western periphery on the
ongoing storms (i.e. from southeast/south-central TX into southwest
TX) later this afternoon and this evening. This redevelopment will
be supported by a combination of moist advection, modest heating,
and limited low-level convergence. Moderate to strong buoyancy amid
moderate vertical shear could support supercells if the mode remains
discrete. However, the weakness in the mid-level flow suggests
storms may tend to cluster, a scenario that is supported by most CAM
guidance. Buoyancy and shear are still strong enough to support
rotating updrafts and large hail early in the convective cycle, but
the trends towards a messy convective mode could limit the
persistence and coverage of robust updrafts. Damaging gusts are
possible even with the clustered storm mode, especially given there
is some potential for slightly more organized bowing segments over
time.
Farther west, mid-level height rises/subsidence are anticipated
coincident with the dryline from central Kansas south-southwestward
across western Oklahoma and west/southwest Texas. The environment,
characterized by 1500 to 2000 J/kg of MLCAPE and 30 to 40 kt of
westerly deep-layer shear, is conditionally supportive of supercells
capable of all severe hazards. However, the previously mentioned
height rises and subsidence, combined with modest convective
inhibition, are generally expected to preclude thunderstorm
development. Even so, given the conditional risk, Marginal risk
probabilities will be maintained.
...Minnesota/Wisconsin...
Recent surface analysis places a low just west of FAR, with a warm
front extending southwestward across central/southeast MN and
southern WI. This low is forecast to move eastward today, while the
warm front expands northward. A narrow corridor of surface-based
buoyancy could develop from north-central MN into far northwest WI
as dewpoints increase in the upper 50s (perhaps even low 60s).
Thunderstorm initiation appears possible along the cold front within
this corridor, although veered low-level flow and northward/westward
displacement of the better forcing casts doubt to whether updrafts
will be maintained. Any storms that do mature within this warm
sector should become supercells capable of all severe hazards,
including large hail and tornadoes. However, low confidence in storm
development and maturity precludes higher probabilities with this
outlook.
...Northern Rockies...
Mid-level moisture will support another day of modest surface-based
buoyancy ahead of the shortwave trough mentioned in the synopsis.
Persistent 30-40 knot flow within the CAPE-bearing layer combined
with somewhat deep boundary-layer mixing will support strong to
severe downburst winds with the more robust convective cells, mainly
this afternoon through early evening.
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0230 PM CDT Sun Apr 12 2026
Valid 141200Z - 151200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF
THE SOUTHERN PLAINS TO THE GREAT LAKES...
...SUMMARY...
Isolated to scattered severe thunderstorms are expected on Tuesday
and Tuesday night from the Southern Plains to the Great Lakes.
...Synopsis...
The western US trough will eject across the Rockies on Tuesday with
strengthening westerly flow overspreading the Plains into the Great
Lakes Region. A surface low will deepen across western KS/NE with a
warm front lifting across the Lower Missouri Valley into the Great
Lakes and sharpening dryline across the southern/central Plains. A
cold front will sag southward across the Upper Midwest/Great Lakes
vicinity. The surface trough/dryline and the boundary across the
Great Lakes will become a focus for thunderstorm activity through
the forecast period.
...Lower MO Valley to the Great Lakes...
Convective coverage will overlap the start of the period near 12z on
Tuesday across portions of the Midwest/Great Lakes Region. Trends
are for relatively quick clearing across portions of central Iowa
into Illinois. As the warm front lifts northward, strong daytime
heating is expected amid dew points in the low to mid 60s. It is
likely the air mass will recover with potential for moderate to
strong instability by the afternoon. Stronger height falls are not
expected across the region, as the main upper trough
will be focused well to the southwest. However, warm advection atop
a southward-sagging surface boundary should support isolated to
scattered storm development by late afternoon/evening. The primary
risk will be for large to very large hail ( some 2.5"+ in diameter)
and damaging wind.
By late afternoon/evening, 700 mb flow will strengthen (around 50-60
kts) with a plume of steep low to mid-level lapse rate nosing into
central Iowa/northern Illinois from the southwest. The 850 mb
low-level jet also increases, with large clockwise curved hodographs
developing with the resulting increase in low-level shear. If
supercells can develop and maintain residency along or south of the
warm front, a corridor of greater tornado risk (a couple of which
may be strong tornadoes) may present itself.
Consideration was given to a 30 percent area (primarily hail
driven). With some uncertainty remaining in morning convection and
coverage of storms in the afternoon/evening, the 15% was maintained
with this outlook until more information can be gleaned from hi-res
guidance.
...Southern Plains...
Ahead of the dryline across the Southern Plains, strong daytime
heating is expected. Large-scale ascent will begin overspreading the
region by late afternoon/evening as the western upper trough finally
begins to eject eastward. As this occurs, mixing and convergence
along a surface dryline should support storm development by around
00z. If little convective development occurs on D2/Monday, a
relatively undisturbed moist/very unstable air mass will be in
place. It is likely that rather robust thunderstorm development will
occur along the dryline, with the primary mode being supercelluar.
Large to very large hail (2 to locally 2.5+ inches in diameter),
damaging wind, and a couple of tornadoes will be possible. Given
that deep layer shear profiles have more of a parallel component to
the dryline, storm interactions may keep the period of more discrete
supercell thunderstorms short, with a shift to clusters of mix-mode
supercell and multi-cell storms.
..Thornton.. 04/12/2026
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0233 PM CDT Sun Apr 12 2026
Valid 131200Z - 141200Z
...CRITICAL FIRE WEATHER AREA FOR SOUTHEAST COLORADO AND ADJACENT
HIGH PLAINS...
...CRITICAL FIRE WEATHER AREA FOR EASTERN WYOMING...SOUTHWESTERN
SOUTH DAKOTA AND NORTHWESTERN NEBRASKA...
...Appalachians and Mid-Atlantic...
A surface trough accelerating eastward into Quebec along with an
evolving subtropical ridge over the Atlantic will support dry,
southwesterly flow across portions of the Appalachians and
Mid-Atlantic, resulting in sustained southwest winds of 10-15 mph
Monday. The lack of appreciable Gulf moisture return should promote
relative humidity in the 25-35% range across the TN Great Valley
with RH as low as 20% across portions of VA. Increasing cloud cover
and along with some shower and thunderstorm activity should limit
fire weather concerns farther north across the OH River Valley.
Although RH will be marginally higher than D1/Sunday observed
values, fuels remain extremely dry and quite receptive to wildfire
spread. The existing Elevated highlights across VA were extended
southwestward into eastern TN with convection likely remaining well
to the north across KY and WV.
...Central and Northern Plains...
A mid-level perturbation embedded within broad southwest flow aloft
coupled with a lee surface low across the Northern Plains will
result in windy and dry conditions for portions of the central and
northern Plains. Introduced Critical Highlights from eastern WY,
southwestern SD and northwestern NE where west winds of 20-25 mph
(locally 30 mph) will align with relative humidity of 10-15% by
mid-afternoon amid a dry and well-mixed boundary layer. These
conditions will align with dry and receptive fuels to promote a
critical fire weather concern. Farther south, a mid-level jet
ejecting into the Southern Plains combined with lee troughing across
High Plains will support a Critical fire weather threat for the
region Monday. Southwest winds of 20-25 mph and RH reductions into
the 10-15% range are likely to evolve by peak afternoon heating.
However, a complex fuels arrangement exists across the Southern
Plains with some modification and reduced receptivity noted from
recent rainfall. Alignment of fire-effective meteorological
conditions and most receptive fuels will exist across southeastern
CO, far northeastern NM, far southwestern KS and adjacent OK/TX
Panhandles where Critical Highlights were largely maintained.
..Williams.. 04/12/2026
.PREV DISCUSSION... /ISSUED 0203 AM CDT Sun Apr 12 2026/
...Synopsis...
Broad southwesterly mid level flow in advance of a trough
progressing from California into the Great Basin will be responsible
for widespread dry and windy conditions from southeastern New Mexico
all the way into portions of eastern Wyoming and South Dakota.
Critical fire-weather concerns are forecast for portions of
southeastern Colorado into portions of far western Kansas and
northern New Mexico.
...Eastern New Mexico/Adjacent High Plains...
Critical fire-weather conditions are forecast for southeastern
Colorado into portions of far northeastern New Mexico and far
western Kansas. Minimum relative humidity of 10-15% and winds of 25
MPH will overlap with critically receptive fuels. While Critical
meteorological conditions appear they could extend further south and
west of the current area, recent wetting rainfall and a lack of
receptive fuels currently limit the expansion of highlights. Still,
there are some pockets of receptive fuels in portions of Oklahoma
into the Texas Panhandle that have yet to receive rain, and some
additional highlights may be warranted in future updates. A
secondary area of concern in the ensemble guidance could be portions
of northern Nebraska into South Dakota/Wyoming, where some members
have come in with winds of 25-30 MPH and relative humidity of 10-15%
over receptive fuels. However, ensemble spread in the surface winds
reduces confidence to introduce these highlights, especially given
the members with the strongest winds are models that tend to bias
towards aggressive mixing. Still, this area will be monitored for
additional highlights in future updates.
...Mid Atlantic...
Dry southeasterly return flow is forecast across portions of North
Carolina into much of Virginia, where fuels currently exceed the
95th-99th annual percentiles for ERCs. Winds are expected to reach
10-15 MPH with relative humidity around 25-35%, supporting Elevated
fire-weather concerns.
...Please see www.spc.noaa.gov/fire for graphic product...
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