SPC Jun 5, 2026 1300 UTC Day 1 Convective Outlook

LIVE MAP (ABOVE) ... SPC 1300Z Day 1 Outlook


Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0700 AM CDT Fri Jun 05 2026

Valid 051300Z - 061200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND
EVENING FROM NEBRASKA/KANSAS INTO NORTHERN ILLINOIS...

...SUMMARY...
Thunderstorms with large hail and severe wind gusts are expected to
develop late this afternoon and evening from parts of the central
Plains into the mid Missouri and mid Mississippi Valleys. Isolated
severe wind gusts and hail will also be possible in parts of the
upper Mississippi Valley.

...NE to IA...
A large upper ridge is present today across the southern U.S., with
stronger westerlies over the northern tier of states. One shortwave
trough is noted over SD tracking east-southeastward. This feature
will provide large-scale ascent to parts of the Midwest states
today, leading to scattered clusters of thunderstorms. One area of
expected convective initiation will be late this afternoon along a
retreating surface boundary extending from south-central NE into
southern IA. Ample low-level moisture will reside in the frontal
zone with dewpoints in the low 70s and MLCAPE values over 3000 J/kg.
Activity should develop around 00z along the boundary and track
slowly eastward. Sufficient deep-layer shear suggests a risk of
supercells capable of large hail. Low-level winds are not expected
to be particularly strong, limiting a more robust tornado risk.
Activity will likely congeal and track eastward across southern
IA/northern MO and eventually northern IL through the evening with a
hail/damaging wind risk.

...Northern IL to Lower MI...
A large decaying MCS is moving across northern MO this morning.
While this activity will likely remain non-severe through the
morning, potential for re-intensification exists this afternoon as
activity moves into northern IN and southern lower MI. If
sufficient daytime heating can occur, steep lapse rates and
mesoscale organization of the MCS could result in sporadic damaging
winds.

...MI/WI...
A broad area of 60s dewpoints and broken cloud cover will lead to
moderate CAPE values this afternoon from southern MN into much of
WI. As the aforementioned shortwave trough approaches this
afternoon, cooling aloft and strengthening wind fields will promote
organized structures with any convection that can form. Model
guidance varies considerably on the cover of storms in this area,
but a conditional risk of large hail and damaging winds is present.
Will maintain only MRGL risk for this area for now, but an upgrade
to SLGT could be needed today if later model guidance indicates
greater coverage of afternoon/evening storms.

..Hart/Wendt.. 06/05/2026


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SPC Jun 5, 2026 0600 UTC Day 1 Convective Outlook

LIVE MAP (ABOVE) ... SPC 1200Z Day 1 Outlook


Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0230 AM CDT Fri Jun 05 2026

Valid 051200Z - 061200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE CENTRAL PLAINS...AND MID MISSOURI AND MID MISSISSIPPI VALLEYS...

...SUMMARY...
Thunderstorms with large hail and severe wind gusts are expected to
develop late this afternoon and evening from parts of the central
Plains into the mid Missouri and mid Mississippi Valleys. Isolated
severe wind gusts and hail will also be possible in parts of the
upper Mississippi Valley from this afternoon into the early evening.

...Central Plains/Mid Missouri and Mid Mississippi Valleys...
At mid-levels, a shortwave trough and an associated jet streak will
move eastward today from the northern Plains into the upper
Mississippi Valley. At the surface, a low will deepen across
northeast Kansas, with a trough in place from the low northeastward
into western Iowa. Moisture advection will occur to the east of the
low across the mid Missouri Valley, where surface dewpoints will
increase into the upper 60s and lower 70s F. As surface temperatures
warm today, a pocket of strong instability will develop from
northeast Kansas and southeast Nebraska into southwest Iowa.
Convective initiation will be hampered by a capping inversion in
place throughout much of the afternoon. The cap is forecast to
weaken during the late afternoon or early evening, which will allow
for convective initiation. Thunderstorms are expected to develop
along the northern edge of the stronger instability near the surface
trough. This convection will likely move east-southeastward across
eastern Nebraska and south-central Iowa during the early to mid
evening. Storms will eventually affect parts of northern Missouri
and north-central Illinois.

RAP forecast soundings in the early evening to the south of Omaha
and Des Moines have MLCAPE in the 3000 to 4000 J/kg range with 0-6
km shear around 35 knots, and 500-700 mb lapse rates near 7.5 C/km.
This environment will support supercells with large hail. Hailstones
greater than 2 inches in diameter will be possible with the more
dominant supercells. Cell coverage is expected to steadily increase
during the early to mid evening. This should result in a transition
to linear mode with a line gradually becoming organized. During this
process, the potential for wind damage is expected to increase, and
a few wind gusts could exceed 70 mph along the more intense parts of
the line. The wind-damage threat will likely develop eastward across
parts of the mid Mississippi Valley during the mid to late evening,
as either the line approaches from the west or more storms initiate.

...Upper Mississippi Valley...
A mid-level shortwave trough will move eastward into the upper
Mississippi Valley today, where a moist and unstable airmass will be
in place. Scattered thunderstorms are expected to develop ahead of
the trough during the afternoon across parts of central Minnesota
and central to northern Wisconsin. These storms will move eastward
toward the Great Lakes during the late afternoon and early evening.
MLCAPE in the 1500 to 2500 J/kg range, along with 0-6 km shear of 30
to 35 knots will support an isolated severe threat. A potential for
severe wind gusts and hail will be possible with the stronger short
multicell line segments.

..Broyles/Lyons.. 06/05/2026


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SPC Jun 5, 2026 0100 UTC Day 1 Convective Outlook

LIVE MAP (ABOVE) ... SPC 0100Z Day 1 Outlook


Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0757 PM CDT Thu Jun 04 2026

Valid 050100Z - 051200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE NORTHERN PLAINS...

...SUMMARY...
Severe thunderstorms capable of large to very large hail and
damaging winds are possible this evening across much of South Dakota
into parts of northern Nebraska and south-central Minnesota.
Isolated large hail and severe wind gusts will also be possible in
parts of the central Plains and mid Missouri Valley.

...Northern Plains/Upper Mississippi Valley...
At mid-levels, west-southwesterly flow is evident over much of the
north-central U.S. A shortwave trough is evident on water vapor
imagery over the far western Dakotas. At the surface, a 1002 mb low
is analyzed in eastern Wyoming with a quasi-stationary front
extending northeastward into central South Dakota and north-central
Minnesota. An axis of low-level moisture is located from near the
Black Hills east-northeastward across South Dakota into
south-central Minnesota, where surface dewpoints are in the lower to
mid 60s F. Along and near this axis, the RAP has MLCAPE mostly in
the 1500 to 2500 J/kg range. Scattered strong to severe
thunderstorms are ongoing near the instability axis in the vicinity
of the Black Hills in southwestern South Dakota. The latest 00Z
sounding at Rapid City has 0-6 km shear around 50 knots with 700-500
mb lapse rates near 8 C/km. This will support supercells with large
hail. Hailstones of greater than 2 inches in diameter will be
possible for a few more hours this evening. The wind-damage threat
will likely increase if a cell cluster can become organized and move
into central South Dakota later this evening...see MCD 983. The
southern edge of any cluster could impact parts of northern Nebraska
later this evening.

Further east into eastern South Dakota, a cluster of strong to
severe thunderstorms is ongoing. The 00Z sounding at Aberdeen has
MUCAPE around 1800 J/kg with 0-6 km shear near 40 knots, and a
700-500 mb lapse rate just above 7 C/km. This should support
supercells with large hail early this evening. 0-3 km lapse rates
near 7.5 C/km will also be favorable for severe wind gusts. The
severe threat is expected to increase in southeast and central
Minnesota later this evening, as the storms in eastern South Dakota
move along the instability axis.

...Central Plains/Mid Missouri Valley...
A mid-level shortwave trough is evident on water vapor imagery over
eastern Kansas. At the surface, a moist airmass is in place from
much of central and eastern Kansas northeastward into Iowa, where
surface dewpoints are in the upper 60s to near 70 F. Moderate to
strong instability is analyzed by the RAP from central Kansas into
far western Missouri. Scattered thunderstorms are ongoing along the
northern edge of the stronger instability from northeast Kansas into
southwest Iowa. These storms are being supported by a low-level
speed max of 35 to 45 knots, and could be associated with a threat
for isolated severe wind gusts and hail this evening. As low-level
flow increases from this evening into the overnight period, the
redevelopment of storms may occur over parts of central and eastern
Kansas, where a continued marginal severe threat will be possible.

..Broyles.. 06/05/2026


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SPC Jun 4, 2026 1630 UTC Day 1 Convective Outlook

LIVE MAP (ABOVE) ... SPC 1630Z Day 1 Outlook


Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1128 AM CDT Thu Jun 04 2026

Valid 041630Z - 051200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND
EVENING OVER 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.

...Southeast MT through the Dakotas into southern MN...
Morning surface analysis places a weakening cold front from
northwest MN through south-central SD to a weak low near the
WY/SD/NE border intersection. Western portion of this boundary (from
central SD westward) is forecast to stall, with perhaps some retreat
northward during the late afternoon, while the eastern portion over
MN progresses slowly eastward. Dewpoints will likely stay in the 60s
along this boundary, with moderate to strong buoyancy developing by
late afternoon. Moisture convergence, augmented by modest
large-scale ascent attendant to a shortwave moving across MT, will
likely result in scattered convective initiation by the late
afternoon. Additional storms are expected farther west across
eastern MT ahead of the aforementioned shortwave. Moderate
deep-layer shear will support occasional supercells, with large to
isolated very large hail as the primary risk. Storms will spread
into the central Dakotas through the evening with a continued severe
threat.

Farther east, late afternoon thunderstorm development is expected
along the cold front. Deep-layer shear will be weaker than areas
farther west, and a more outflow-dominant storm mode appears likely.
Isolated hail is still possible early in the convective cycle,
particularly into central SD where steeper mid-level lapse are
expected.

...Central/Eastern KS into southeast NE/northwest MO/western IA...
Morning satellite imagery shows a well-defined MCV over western KS,
with widespread cloud cover throughout its eastern periphery from
central KS across south-central and eastern NE. Surface observations
show dewpoints in the mid 60s beneath this cloud cover, with
temperatures ranging from the upper 60s across central KS to the mid
70s across southwest IA. Southerly flow is anticipated throughout
the day today, maintaining low-level moisture advection within this
corridor. This increasing moisture coupled with sheltered/cloudy
conditions will likely result in dewpoints climbing into the upper
60s (perhaps even some low 70s) across this region by the late
afternoon. Modest heating is anticipated as well, with temperatures
likely in the mid 70s to low 80s. Mid-level lapse rates are poor
(generally less than 6 deg C per km from 700 to 500 mb), but the
ample low-level moisture will still support afternoon/late afternoon
MLCAPE around 1500 to 2000 J/kg and little, if any, convective
inhibition.

Ascent attendant to the MCV and low-level convergence throughout its
eastern periphery will support widespread thunderstorm development
within this unstable and uncapped environment. Deep-layer shear will
be weak (less than 25 kt from 0-6 km) across much of the region,
with a largely multicellular mode anticipated. That being said, an
increase in low-level southerly flow is expected throughout the
eastern periphery of the MCV, contributing to some moderate
lengthening of the low-level hodograph. This stronger low-level
southerly flow combined with the ample moisture in place (i.e. PW
values approaching 1.8" by the late afternoon, which is above the
90th percentile at TOP) results in a unique environment supportive
of brief tornadoes. Even so, the lack of stronger deep-layer shear
still suggests a predominantly disorganized storm mode, which should
keep any tornado threat isolated enough to keep probabilities at 2%.
A few water-loaded downbursts are possible as well.

..Mosier/Chalmers.. 06/04/2026


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