RSS Mesoscale Discussions from Storm Prediction Center
No watches are valid as of Wed Jul 8 18:18:01 UTC 2026.
MD 1541 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR SOUTHEAST MINNESOTA INTO CENTRAL WISCONSIN
Mesoscale Discussion 1541
NWS Storm Prediction Center Norman OK
0115 PM CDT Wed Jul 08 2026
Areas affected...Southeast Minnesota into central Wisconsin
Concerning...Severe potential...Watch possible
Valid 081815Z - 082015Z
Probability of Watch Issuance...60 percent
SUMMARY...Isolated large hail and damaging winds are the primary
concerns with widely scattered to scattered storms this afternoon. A
watch is possible should convective trends warrant.
DISCUSSION...Thunderstorms have initiated near a stationary boundary
in southern Minnesota. This activity is tied to an upstream
shortwave trough in western Minnesota per water vapor imagery.
Filtered heating through cirrus clouds has allowed temperatures to
rise into the low/mid 80s F. The very moist air will support around
1500 J/kg MLCAPE. Continued heating and increasing mid-level ascent
will eventually lead to widely scattered to scattered storms.
Isolated damaging winds and hail may occur with the strongest
storms, though low/mid-level lapse rates are not overly steep. The
surface reflection of the shortwave trough is also rather nebulous.
Even so, low-level shear is sufficient for weakly rotating storms
conditionally capable of a brief tornado. A watch may be needed this
afternoon.
..Wendt/Hart.. 07/08/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...GRB...MKX...ARX...MPX...DMX...
LAT...LON 43329122 43369242 43349357 43549433 44199412 44869066
44888941 44618906 44128887 43748892 43608911 43548969
43329122
MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
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SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1112 AM CDT Wed Jul 08 2026
Valid 081630Z - 091200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PARTS OF
NORTHEAST COLORADO...SOUTHWEST NEBRASKA...AND NORTHWEST KANSAS...
...SUMMARY...
Thunderstorms with severe wind gusts and hail will be possible this
afternoon and evening across parts of the central Plains, and from
the Missouri Valley into the upper Mississippi Valley. Isolated
severe gusts may also occur from the northern Great Basin into the
northern High Plains, from North Carolina into southern Virginia,
and over southeast Arizona.
...WI/MN/IA...
A fast-moving shortwave trough is moving eastward across ND. As
this system approaches the western Great Lakes region this
afternoon, thunderstorms are expected to form along a surface
boundary extending from southeast MN into central WI. A moist and
very unstable air mass will be present along the boundary, aiding in
the development of a few severe storms. Sufficient deep-layer shear
will promote supercell structures capable of damaging wind gusts and
hail. An isolated tornado or two is also possible. This activity
will build westward along the boundary into northern IA by early
evening. A cluster or two of this activity could congeal into
bowing structures with a continued severe wind risk this evening.
...High Plains...
The upper ridge over the Rockies has weakened today, resulting in
stronger westerly flow into parts of WY/CO/NE/KS. Scattered
high-based thunderstorms are expected to form by mid-afternoon over
the mountains and foothills of CO/southern WY and spread eastward
into the Plains. Moisture will be limited near the foothills, but
weak easterly surface winds will maintain 40s dewpoints in eastern
CO, leading to convective intensification. Most CAM solutions show
thunderstorms capable of locally severe wind gusts tracking eastward
through the evening into parts of southwest NE and western KS before
dissipating after midnight.
...Northern Great Basin/Northern Rockies...
Moderately strong westerly flow aloft, steep low-level lapse rates,
and ample mid-level moisture will result in conditions favorable for
scattered high-based thunderstorms over a relatively broad area this
afternoon and evening. Gusty/damaging winds will be possible with
the strongest storms.
...Southeast AZ...
Widely scattered high-based thunderstorms are expected to form over
the higher terrain of southeast AZ and propagate south-southwestward
through the early evening. Inverted-v profiles will promote a risk
of gusty/damaging winds in a few of the storms.
..Hart/Chalmers.. 07/08/2026
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SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1201 PM CDT Wed Jul 08 2026
Valid 091200Z - 101200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE PARTS
OF THE NORTHERN AND CENTRAL PLAINS...THE LOWER MO AND OH
VALLEYS...AND THE MID-ATLANTIC...
...SUMMARY...
Severe thunderstorms posing a risk for strong gusts and/or large
hail are possible across portions of the northern and central
Plains, the Lower Missouri to Lower Ohio Valleys, and across the
Mid-Atlantic on Thursday afternoon and evening.
...Lower MO to Lower OH Valleys...
One or more MCVs are forecast to be located over the Lower MO/Mid-MS
Valley vicinity Thursday morning. As these features migrate eastward
through the day, locally enhanced vertical shear will combine with a
very moist and strongly unstable airmass to provide support for
widely scattered organized severe convection. Thunderstorm clusters
will mainly pose a risk for damaging winds and isolated hail. An
initial cluster may develop across eastern MO/southern IL and shift
east along the Lower OH Valley. Some guidance suggests a second
cluster may develop across southern MO and move east/southeast
across the Mid-South vicinity and eventually into TN overnight. An
increasing southerly low-level jet during the evening could maintain
some severe risk even into the nighttime hours across the Mid-South
into TN and severe probabilities have been expanded some across this
area to reflect this potential. Otherwise, the forecast remains
largely similar to the previous Day 2 outlook.
...Northern/Central Plains...
Several shortwave impulses are forecast to migrate across the region
within northwesterly flow aloft. At the surface, a pocket of richer
boundary layer moisture is forecast across the central Plains, with
more modest moisture expected northward into the Dakotas. Strong
heating along a surface trough and steep midlevel lapse rates will
support pockets of 1500-2500 J/kg MLCAPE. Initial supercell
structures are possible across the High Plains and will pose a risk
of large hail and damaging gusts. With time, sufficient
clustering/outflow consolidation is expected and one or more linear
segments will evolve into portions of western KS/NE. Severe gust
potential will increase as this occurs during the evening hours.
Further north into North Dakota, a separate area of supercell
potential is expected as a weak surface low moves east along the
international border near eastern MT/western ND. Isolated supercells
developing ahead of an approaching surface front will pose a risk
for mainly large hail and strong gusts during the evening.
...Mid-Atlantic...
Strong daytime heating of a very moist airmass will result in
1000-2000 J/kg MLCAPE. While deep-layer flow will remain modest,
forecast soundings do indicate around 25-30 kt effective shear
magnitudes. This may allow for some organization of thunderstorm
clusters by late afternoon. Most CAMs guidance indicate a
forward-propagating cluster moving across the DelMarVa area and
offshore the Mid-Atlantic coast by evening. Sufficient coverage of
storms and expected damaging gust potential appears high enough to
upgrade to a Slight (level 2 of 5) risk.
...AZ...
Thunderstorms are expected to develop across the higher terrain of
southeast AZ/southwest NM Thursday afternoon. Steep lapse rates will
support around 1000 J/kg MLCAPE. This activity may pose a risk for
isolated severe gusts as convection shifts southwest across lower
elevated through evening.
...Lower Great Lakes vicinity...
Isolated thunderstorms are expected to develop within modest
instability ahead of a southward-sagging surface boundary on
Thursday. Gusty winds may accompany this activity, but severe
potential will likely be limited by poor lapse rates and modest
instability.
..Leitman.. 07/08/2026
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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1140 AM CDT Wed Jul 08 2026
Valid 081700Z - 091200Z
...Morning Update...
No changes were made to the ongoing forecast. A dry cold front has
moved into northwestern Washington as of 12z this morning, and is
expected to continue eastward to reach southeastern Oregon by this
evening. Latest high resolution guidance depicts RH values will
decline to 12-20% (locally lower) and gusty winds will increase to
20-30 mph (up to 35 mph or greater in terrain-favored areas),
overspreading the Columbia Basin and eastern Oregon behind the
front. These weather conditions amid 80-95th percentile ERCs
maintain widespread elevated and locally critical fire concerns this
afternoon. After several consecutive days of mixed wet/dry
thunderstorms, some relief to the fire environment has been observed
across the West Slope in the form of better RH recoveries (as
compared to the last 7 days). However, such relief is short-lived,
as RH values are expected to decline to 15-20% this afternoon in far
western CO with residual mid-level moisture and daytime instability
encouraging mixed wet/dry thunderstorms to develop once again. See
the previous discussion for more information.
..Elizalde-Garcia.. 07/08/2026
.PREV DISCUSSION... /ISSUED 1245 AM CDT Wed Jul 08 2026/
...Synopsis...
An upper-level trough will move into southwest Canada, and an
upper-level high will slowly shift southwest off the southern
California coast. Between these two features, west-southwest flow
aloft will spread over the West, with embedded weak disturbances
rotating through. A dry Pacific cold front will push through the
Northwest and into the northwest Great Basin and northern Rockies as
a thermal trough extends from the Gulf of California into the
central Great Basin.
As the cold front moves through the Northwest, west-northwest
sustained winds of 12-20 mph with gusts of 20-30 mph are likely amid
minimum RH of 12-25% across much of the Inland Northwest. Ahead of
the front, a dry airmass remains with minimum RH of 5-15% expected.
West-southwest sustained winds of 12-20 mph and gusts of 20-30 mph
are likely to overlap this dry airmass across much of the Great
Basin and into southeast California, northern Arizona, and far
western Colorado.
Isolated to scattered mixed wet/dry thunderstorms are likely across
the northern Great Basin into the Four Corners. While pockets of
wetting rain have been observed across the IsoDryT area, fuels
remain receptive, including near to record dry fuels in portions of
Utah and Colorado. Some consideration was given to removing the
IsoDryT along the Nevada/Idaho/Utah borders due to potential wetting
rain. Ensemble forecast guidance indicates a 50-80% chance of
rainfall exceeding 0.1", but less than a 25% chance to exceed 0.25".
Additionally, due to expected thunderstorm development in the early
to mid-afternoon and scattered coverage of storms, portions of
southern Idaho, northeast Nevada, and northern Utah may not hit
elevated criteria for wind/RH.
...Please see www.spc.noaa.gov/fire for graphic product...
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