RSS Mesoscale Discussions from Storm Prediction Center
No watches are valid as of Sat Jun 27 09:01:02 UTC 2026.
No Mesoscale Discussions are in effect as of Sat Jun 27 09:01:02 UTC 2026.
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1233 AM CDT Sat Jun 27 2026
Valid 271200Z - 281200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS LATE THIS
AFTERNOON INTO EARLY TONIGHT ACROSS EASTERN MT AND WESTERN ND...
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS INTO WESTERN SOUTH
DAKOTA AND NEBRASKA...AND ACROSS NORTH CAROLINA...
...SUMMARY...
A mix of initial supercells and later storm clusters will produce
swaths of severe outflow winds and very large hail across the
northern High Plains late this afternoon into early tonight.
Isolated wind damage will also be possible from the Mid-Mississippi
Valley to the Carolinas, as well as across west Texas and the Texas
Panhandle.
...Northern High Plains this afternoon into tonight...
Embedded speed maxima will rotate northeastward over the northern
High Plains, around the eastern periphery of a close midlevel low
evolving over the northern Great Basin and northern Rockies.
Boundary-layer dewpoints in the 60s will continue to spread
northward from KS/NE to the Dakotas, east of a deep lee
trough/cyclone across the central/northern High Plains. The
moistening will occur beneath steep midlevel lapse rates, which
combined with daytime heating will result in large CAPE.
Thunderstorm development is expected this afternoon along both the
surface trough/lee cyclone near the MT/ND border and near the Big
Horn Mountains. The initial storms could be supercells with very
large hail (2-3 inch diameter) near the ND/MT border, and a couple
of tornadoes with any supercells anchored along the surface
boundary, though relatively large temperature-dewpoint spreads and
mode concerns could temper the tornado threat somewhat. By late
evening and early tonight, storms will likely grow upscale and move
northeastward across ND as one or more MCSs with severe outflow
winds (potentially 80+ mph) in the steep lapse rate environment.
More isolated supercells will also be possible farther south into
western SD/NE where isolated very large hail and significant severe
outflow gusts will be possible.
...TN/southern KY to NC this afternoon...
An MCV now over eastern KY will continue eastward near the VA/NC
border during the day, and additional MCVs are likely to emerge from
ongoing storm clusters moving eastward across OK, southwest KS and
the TX Panhandle. Ascent with the MCVs, as well as residual
outflow/differential heating zones, will help focus thunderstorm
development during the afternoon in a moist, unstable environment.
Occasional wind damage will be possible with storm clusters where
low-level lapse rates are relatively steep (south of persistent
clouds) and there is some enhancement of midlevel flow. An isolated
tornado may also occur in the warm advection zone with enhanced
low-level hodograph curvature across TN on the southwest flank of
the western MCV, though confidence in this scenario is low.
...TX Panhandle into west TX late this afternoon/evening...
Though forcing for ascent will be weak at best this far south,
strong surface heating/mixing along the lee trough/dryline could
support high-based thunderstorm development late this afternoon.
Inverted-V profiles will favor the potential for isolated severe
outflow gusts of 60-75 mph.
..Thompson/Chalmers.. 06/27/2026
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SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1259 AM CDT Sat Jun 27 2026
Valid 281200Z - 291200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PORTIONS OF NORTH
DAKOTA AND NORTHERN MINNESOTA...
...SUMMARY...
Severe thunderstorms are possible from the northern Plains into
parts of the Upper Midwest on Sunday. Large hail and severe winds
are the primary hazards.
...Synopsis...
The western U.S. trough will remain in place on Sunday with an
amplifying upper ridge in the East. A surface low is expected to
develop within the central/northern High Plains, though the location
is still uncertain. A surface boundary will be present from the
Mid-Atlantic through the Ohio Valley and mid Mississippi Valley.
...Northern Plains/Upper Midwest...
The forecast remains rather complex across these regions. Convection
is generally expected to be ongoing during the early morning across
parts of eastern North Dakota into northern Minnesota. While this
activity is not expected to be particularly strong, it may modulate
the northward progression of a surface boundary. In the wake of the
morning activity, at least a narrow zone of moderate buoyancy
(2000-2500 J/kg MLCAPE) is expected to develop in central/eastern
North Dakota. Nebulous mid-level ascent casts some doubt on whether
storms will be able to form on an outflow boundary/surface trough.
Should storms develop, they may only be surface based for a short
period if at all. 50+ kt of effective shear and sufficient mid-level
lapse rates will support some risk of large hail and severe winds.
During the evening/overnight, the surface low is expected to deepen
somewhere in the High Plains. Storm development is possible as this
occurs. Where this occurs is still uncertain, but the Nebraska
Panhandle into western South Dakota are currently the most probable.
If convection can develop, it will most likely be elevated in
nature. The strong low-level jet would likely support some eastward
progress. Damaging winds and isolated large hail could occur with
this activity.
...Southern Mid-Atlantic...
Guidance continues to depict an MCV moving through the region. The
timing and intensity of this feature has been variable in the last
couple of model cycles. Overall deep-layer flow will be weak outside
of the influence of the MCV. Given the moist airmass in place,
widely scattered to scattered thunderstorms are expected ahead of
this feature. Damaging wind gusts are possible, particularly where
storms can cluster.
..Wendt.. 06/27/2026
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SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0230 AM CDT Sat Jun 27 2026
Valid 291200Z - 301200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE
MID-MISSOURI VALLEY INTO THE UPPER MIDWEST...
...SUMMARY...
Severe thunderstorms are possible from parts of the central/northern
Plains into the Upper Midwest on Monday. Large hail and severe winds
are the primary concerns.
...Central/northern Plains into the Upper Midwest...
A shortwave trough is expected to eject into the Dakotas and the
Upper Midwest. The timing and evolution of this feature varies in
model guidance. The ECMWF suggests a later and a more
eastward-moving wave ejection as compared to the earlier, meridional
trajectory of the NAM/GFS. These differences lead to drastic
differences in where convection will ultimately form. The farther
north solutions show little in the way of convection as compared to
the ECMWF. A very moist airmass will be in place along with steep
mid-level lapse rates overspreading the area. The amplified ridge in
the East will remain in place and will suppress thunderstorm
potential away from the trough/cold front. Models all suggest
extreme buoyancy (4500+ J/kg MLCAPE) will develop within the warm
sector. Deep-layer shear will be strong enough for organized storms.
Given the potential for intense storms, a broad Slight will be
maintained with the caveat that convective development is somewhat
conditional/uncertain.
..Wendt.. 06/27/2026
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Day 4-8 Outlook
Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0357 AM CDT Sat Jun 27 2026
Valid 301200Z - 051200Z
...DISCUSSION...
The upper-level pattern from the middle of the new week onward will
be relatively stagnant. The upper ridge in the East will remain
entrenched while broad cyclonic flow will persist in the West before
potentially breaking down by the weekend. This will drive a belt of
weak to moderate mid-level southwesterlies across the
central/northern Plains. Repeated lee trough development along with
the surface high in the East will maintain rich moisture across
parts of the Plains and especially the Midwest/Southeast. With
large-scale features generally being weak, convective development
will largely be reliant on terrain features, subtle shortwave
troughs, or surface boundaries. With this pattern, at least low
severe potential will exist within the northern Plains into the
Upper Midwest into next weekend. Predictability will remain low,
however, as large-scale features will be weaker and the influence of
prior convection will increase with each successive day.
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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0158 AM CDT Sat Jun 27 2026
Valid 271200Z - 281200Z
...EXTREMELY CRITICAL FIRE WEATHER AREA FOR PORTIONS OF WESTERN
COLORADO AND EASTERN UTAH INTO THE FOUR CORNERS REGION...
...CRITICAL FIRE WEATHER AREA FOR MUCH OF SOUTHERN/EASTERN
NEVADA...SOUTHERN/CENTRAL UTAH...WESTERN COLORADO...NORTHEASTERN NEW
MEXICO...NORTHERN ARIZONA...AND SOUTH-CENTRAL WYOMING...
...Synopsis...
***Dangerous fire weather conditions are expected today across
eastern Utah, western Colorado, and the Four Corners region.***
A robust fire weather pattern will continue across portions of the
Great Basin and Southwest today as a seasonably strong mid-level
trough continues to dig into the western CONUS and an attendant
mid-level jet amplifies across portions of the Great Basin.
Continued exceptionally dry and windy conditions following
antecedent dry thunderstorm activity will result in significant fire
weather concerns for any new ignitions, lingering holdovers, and
ongoing large fires across the western CONUS.
...Eastern Utah, western Colorado, and the Four Corners region...
As the aforementioned mid-level jet amplifies across portions of the
Great Basin, a corridor of stronger sustained, southwesterly surface
winds will expand eastward from southeastern Nevada into the Upper
Colorado River Valley. These 25-35 mph (potentially up to 40 mph in
terrain favored locations) winds will overlap very low RH values of
5-15% and receptive fuels (ERCs noted in the 80-95+ percentiles)
that were exacerbated by dry/breezy conditions on Friday. Wind gusts
of 40-50+ mph will also be possible due to deep boundary layer
mixing coupled with the strengthening mid-level jet. This will
promote extremely critical fire weather conditions from the Four
Corners region northward into eastern Utah and western Colorado and
an extended period (10+ hours of for some locations) of critical
fire weather conditions across a broader portion of the Great Basin.
In addition, isolated dry thunderstorm activity on Friday presents
an additional concern for potential lightning holdovers to emerge,
with poor overnight humidity recoveries and lingering breezy
conditions also forecast before another day of critical fire weather
concerns on D2/Sunday. A broader area of elevated wind/RH conditions
is also expected today across much of the Great Basin and Southwest
where sustained southwesterly winds of 15-25 mph overlap low RH of
10-20%.
The primary change with this outlook was a northward expansion of
the Extremely Critical highlights owing to trends within the latest
model guidance. Brief periods of localized extremely critical
conditions are also possible farther west into southeastern Nevada
and portions of north-central Arizona (in the vicinity of recent
wildfire activity); however, confidence in an extended duration of
overlap between 30+ mph sustained winds and RH below 10% is lower
for these locations.
..Chalmers.. 06/27/2026
...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
0159 AM CDT Sat Jun 27 2026
Valid 281200Z - 291200Z
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE FOUR CORNERS
REGION...
...Synopsis...
An upper-level trough centered within the Intermountain West will
begin to pivot northeastward on D2/Sunday, with an associated
mid-level jet continuing to be oriented across the Four Corners
region and a cold front progressing slowly southeastward, and
potentially stalling, across the West. This will continue to promote
robust fire weather concerns across portions of the Great Basin and
Southwest.
...Four Corners region...
A third consecutive day of enhanced sustained surface winds of
20-25+ mph and dry RH of 10-20% is forecast across portions of the
eastern Great Basin and Southwest on Sunday. Latest guidance
continues to depict a corridor of 20-25 mph sustained southwesterly
winds (with the potential for occasional gusts to 35-40 mph) amid
very low RH of 10-15%. With this multi-day period of dry/breezy
conditions exacerbating fuel dryness/receptiveness (and ERCs already
noted to be in the 80-95+ percentiles), several hours of critical
fire weather conditions are expected Sunday afternoon, extending
from northern Arizona into southeastern Utah, northeastern New
Mexico, and southwestern Colorado. A broader area of elevated fire
weather conditions is expected across adjacent areas of the Great
Basin/Southwest where winds of 15-25 mph are forecast to overlap low
RH of 10-20%.
Minor adjustments were made to the Elevated/Critical highlights with
this cycle based on the latest high-res guidance, including slight
expansions of the Critical and Elevated highlights southward and
westward, respectively.
..Chalmers.. 06/27/2026
...Please see www.spc.noaa.gov/fire for graphic product...
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