LIVE MAP (ABOVE) ... SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1255 AM CDT Thu Jul 02 2026
Valid 021200Z - 031200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE NORTHERN PLAINS INTO THE UPPER MIDWEST...
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THE NORTHERN
PLAINS INTO PARTS OF THE UPPER GREAT LAKES AND MIDWEST AND OVER THE
SOUTHERN APPALACHIANS...
...SUMMARY...
Strong to severe storms will be possible from the northern Plains
into the Midwest and Great Lakes regions, as well as across the
southern Appalachians on Thursday. Isolated strong to severe storms
may also occur in the Tennessee Valley, central High Plains, and
parts of the Northeast.
...Synopsis...
The upper level pattern across the US will be characterized by
troughing across the western US with a high amplitude ridge across
the eastern US. Between these features, several shortwave troughs
will rotate through the flow across the central/northern Plains into
the Midwest. A surface low will be located across eastern Montana
into the western Dakotas, with a surface boundary extending from the
northern Plains into the Upper Midwest.
...Northern High Plains into the Great Lakes and Midwest...
Early morning convection is likely across some portion of North
Dakota in association with a vort max moving out of Montana. The
evolution of this activity will likely have implications on the
exact placement of the surface boundary by this afternoon across the
Dakotas. Afternoon thunderstorm development is expected near the
surface low and in the vicinity of the surface boundary/residual
outflow across the Dakotas by the afternoon. Coverage should
increase as a shortwave moves out of Montana into the
afternoon/evening with increasing forcing for ascent. Across the
northern High Plains, strong daytime heating amid steep low to
mid-level lapse rates will support moderate to strong instability.
This in combination with deep-layer shear around 40-45 kts will
support initial supercells capable of large to very large hail and
damaging wind. Through time, boundary parallel shear and large dew
point spreads promoting outflow dominate storms will likely support
one or more clusters/bowing segments moving south and east with
time, resulting in an increase in the damaging wind threat and
potential for a few significant gust 75+ mph.
...Southern Appalachians into the Tennessee Valley...
A very moist and unstable air mass is expected to be in place across
the Southern Appalachians into the Tennessee Valley this afternoon.
Widely scattered thunderstorms are expected to develop across the
high terrain, with tendency to cluster along outflows. Consensus is
highest across the Appalachians into the Tennessee Valley for a more
focused corridor of damaging wind potential.
...Central High Plains...
Isolated thunderstorms are expected to develop within the lee trough
across the central High Plains this afternoon. Moderate instability
overlapping with around 25-30 kts of deep-layer shear will support
potential for a mix of supercells and multi-cell clusters. Steep
low- to mid-level lapse rates and large temperature/dew point
spreads will support potential for severe gusts. Initial supercells
will pose potential for large hail.
...Northeast...
Northeasterly flow within the northern periphery of the eastern
ridge will allow for thunderstorm activity to track southward out of
Quebec/Ontario across portions of the Northeast this afternoon. The
presence of moderate to strong instability and 30-40 kt
of deep-layer shear will be supportive of organized storm modes with
the predominant hazard being damaging winds. Higher wind
probabilities and a level 2/Slight Risk may be needed with
additional outlook updates if a more favorable corridor of wind
potential become clearer.
..Thornton/Chalmers.. 07/02/2026
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Thursday, July 2, 2026
Wednesday, July 1, 2026
SPC Jul 2, 2026 0100 UTC Day 1 Convective Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0759 PM CDT Wed Jul 01 2026
Valid 020100Z - 021200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
THE UPPER MIDWEST INTO THE GREAT LAKES....
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE NORTHEAST...CENTRAL HIGH PLAINS...
...SUMMARY...
Severe thunderstorms are expected across the Upper Midwest and Upper
Great Lakes this evening. A couple of tornadoes are possible but
damaging wind gusts are expected to be the more widespread hazard,
in addition to isolated large to very large hail. Severe storms also
remain a concern across parts of the central High Plains and the
Northeast.
...Midwest and Upper Great Lakes...
Steadily deepening convective activity has developed across the
surface boundary in southern Minnesota into northern/western Iowa.
Much of this region has been under the influence of a band of
mid-level cloud cover this afternoon. Comparison of the 18z and 00z
observed soundings from OAX indicate inhibition has eroded. Strong
buoyancy also remains across the area amid steep lapse rates and
ample deep layer shear. A southerly low-level jet is progged to
increase through the evening which should further support convective
development. A mix of supercells and clustered multi-cell
thunderstorms is expected through the evening, given largely
boundary parallel shear. With the increase in the low-level jet, a
tornado or two will remain possible with any more discrete
supercells.
...Northeast...
A cluster of thunderstorms is advancing eastward into portions of
northwestern New York just east of Lake Ontario. Sufficient
instability remains across portions of central/southern New York,
with more rain cooled air from several rounds of showers to the
north. This cluster may pose some potential for occasional strong to
severe winds downstream through the evening given remaining warm
temperatures and moist profiles downstream.
...Central and southern High Plains...
Widely scattered thunderstorm activity continues near the dryline
across Kansas into the Oklahoma/Texas Panhandles. The strongest deep
layer shear is located ahead of a short-wave impulse across western
Kansas, where 30-40 kts is analyzed in SPC mesoanalysis. Steep lapse
rates and deeply mixed profiles will support potential for damaging
wind and large hail with supercells through the evening.
...Southeast...
Several clusters of thunderstorms continue across portions of
Mississippi into eastern Louisiana/southern Arkansas this evening. A
few instances of strong to severe wind will continue before gradual
weakening occurs with loss of daytime heating over the next couple
of hours.
..Thornton.. 07/02/2026
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SPC Jul 1, 2026 2000 UTC Day 1 Convective Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0306 PM CDT Wed Jul 01 2026
Valid 012000Z - 021200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
THE UPPER MIDWEST INTO THE GREAT LAKES...
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE NORTHEAST...CENTRAL HIGH PLAINS...AND GULF COAST STATES...
...SUMMARY...
Multiple rounds of severe thunderstorms are still expected across
the Upper Midwest and Upper Great Lakes into tonight. A couple of
tornadoes are possible but damaging wind gusts are expected to be
the more widespread hazard, in addition to isolated large to very
large hail. Severe storms also remain a concern across parts of the
central High Plains, Northeast, and Southeast/Tennessee Valley.
...20Z Update...
The main change made to this outlook was to expand the wind-driven
severe probabilities southward across portions of the Upper Midwest
based on observational trends. A belt of relatively thick cloud
cover exists across portions of the Midwest. However, considerable
clearing and a CU field, along with isolated thunderstorms, has
developed across eastern IA into southern WI, where appreciable
buoyancy (2000-3000 J/kg MLCAPE) and up to 40 kts of effective bulk
shear reside. Furthermore, a few of the latest WoFS runs also depict
some higher thunderstorm coverage across eastern IA into southern
WI. As such, the thinking is that organized severe potential, mainly
in the form of severe gusts, should exist across this region through
the evening.
Otherwise, the previous forecast remains on track, with relatively
minor changes made to the thunder and severe probabilities to
reflect the latest observations and guidance consensus.
..Squitieri.. 07/01/2026
.PREV DISCUSSION... /ISSUED 1156 AM CDT Wed Jul 01 2026/
...Midwest and Upper Great Lakes...
An active multi-round day of severe weather is expected across the
region through tonight. Early this afternoon, ongoing severe risks
will continue to focus across northern Michigan as well as eastern
Wisconsin, with a secondary round of severe storms potentially
spreading into Lower Michigan later this afternoon. See existing
Mesoscale Discussions/Watches for short-term details.
Severe potential later today will focus on a convectively reinforced
boundary, with a very moist and potentially unstable environment
along and south of it. Renewed deep convective development is
expected later this afternoon into tonight across northern Iowa and
southern Minnesota, and again into Wisconsin. A ribbon of moderately
strong mid-level westerlies, some of it MCV-enhanced, will support
organized storm modes including supercells and fast-moving line
segments and potential upscale-MCS development. Large to very large
hail will be possible with the more intense storms in addition to
wind, which may become more prevalent of a hazard (60-80+ mph) as
storm mergers lead to a couple of strong to severe clusters
developing. Some tornado potential may exist as well, particularly
along the effective boundary and/or increasing this evening as a
southwesterly low-level reinvigorates.
...Central and southern High Plains...
High-based thunderstorm development is expected along a
north/south-oriented lee trough/dryline during the afternoon and
evening. Despite modest deep-layer shear (around 25-30 kt), steep
low/mid-level lapse rates will contribute to a strongly unstable
airmass. A mix of loosely organized clusters and possibly some
supercell structures will be capable of producing severe wind gusts
and large hail. Farther south into the southern High Plains, weaker
flow will limit overall storm organization, but steep lapse rates
will support severe gusts with the more intense downdrafts.
...Northeast...
Enhanced west-northwesterly mid-level flow will persist across the
Northeast, where a warm/moist air mass will contribute to around
3000 J/kg MLCAPE, especially across much of New York and
Pennsylvania. While nebulous mesoscale forcing for ascent casts
uncertainty on overall convective coverage and evolution, the strong
buoyancy and a veering wind profile (albeit modest deep-layer shear
quantitatively) will favor east-southeastward-spreading convection
capable of damaging wind gusts and isolated hail during the
afternoon, and again during the evening/nighttime hours.
...Southeast/Tennessee Valley...
Along the southern periphery of a mid-level anticyclone centered
over the central Appalachians, easterly flow through much of the
troposphere resides atop a hot/moist air mass with 3000-4000 J/kg
MLCAPE this afternoon. 12z observed soundings from Atlanta,
Birmingham, and Jackson MS notably sampled 25-35 kt winds between
3-6km AGL, which could aid in storm organization this afternoon. A
somewhat cooler thermal profile aloft was also noted with the 12z
Atlanta sounding with a relatively steep mid-level lapse rate
profile. Strong to severe pulse thunderstorms are expected
regionally, and seemingly with a somewhat greater coverage and
likelihood than a typical pulse-type scenario. The stronger
water-loaded wet microbursts will yield localized gusts of 50-65 mph
and be capable of wind damage.
...Montana and northern Great Basin...
Isolated to widely scattered thunderstorms are expected ahead of a
slow-moving mid-level trough moving across the Northwest. Preceding
the trough, around 40 kt of mid-level southwesterly flow and a
weakly unstable air mass will support a couple loosely organized
clusters capable of producing severe wind gusts during the afternoon
and evening.
Read more CHECK UPDATE ZOOM GRAPHIC
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SPC Jul 1, 2026 1300 UTC Day 1 Convective Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0735 AM CDT Wed Jul 01 2026
Valid 011300Z - 021200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE MIDWEST INTO THE UPPER GREAT LAKES...
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
THE CENTRAL HIGH PLAINS AND THE NORTHEAST...
...SUMMARY...
Scattered severe thunderstorms are forecast across the Upper
Midwest/Great Lakes today and tonight. A couple of tornadoes are
possible but damaging wind gusts are expected to be the more
widespread hazard, in addition to isolated large to very large hail.
Additional severe storms are possible across parts of the central
High Plains and Northeast.
...Midwest and Upper Great Lakes ...
Showers and thunderstorms this morning are moving east over the
Upper Midwest and are associated with a couple of MCVs over
northwest IA and the SD-MN border. The ongoing strong to locally
severe thunderstorm activity is situated in the vicinity of a
west-east oriented frontal zone draped from MN east across WI and
into the U.P. of MI. (see MCD #1413 for short-term details). The
airmass south of the boundary is very moist with lower to mid 70s F
surface dewpoints.
The Sioux Falls, SD (KFSD), Minneapolis, MN (KMPX), and the La
Crosse, WI (KARX) VAD this morning are sampling a belt of strong
southwesterly mid- to high-level flow (50+ kt in the 5-9km ARL
layer). KARX has recently sensed an intensification of flow in the
3-6 km layer, which may influence the threat for wind damage/large
hail beyond an isolated basis and beginning as early as late
morning. Furthermore, it seems the strengthening of flow as
depicted in some model guidance (upwards of 40-45 kt at 700 mb) may
be of consequence for organizing multicells but also supercells
during the day. The details concerning the tornado risk remain
unclear and will likely remain mesoscale dependent and related to
the persistence of morning convection and the airmass recovery, but
it seems plausible the threat for supercell tornadoes would perhaps
focus over WI and possibly extend into southern MN/northern IA this
afternoon in wake of this morning's WAA-driven activity. Large to
very large hail will be possible with the more intense storms in
addition to wind, which may become more prevalent of a hazard (60-75
mph) as storm mergers lead to a couple of strong to severe clusters
developing.
...Central and southern High Plains...
High-based thunderstorm development is expected along a
north/south-oriented lee trough/dryline during the afternoon and
evening. Despite modest deep-layer shear (around 25-30 kt), steep
low/mid-level lapse rates will contribute to a strongly unstable
airmass. A mix of loosely organized clusters and possibly some
supercell structures will be capable of producing severe wind gusts
and large hail. Farther south, weaker flow will limit overall storm
organization, but steep lapse rates will support severe gusts with
the more intense downdrafts.
...Northeast...
Enhanced west-northwesterly midlevel flow will persist across the
Northeast, where a warm/moist air mass will contribute to around
3000 J/kg MLCAPE. While nebulous mesoscale forcing for ascent casts
uncertainty on overall convective coverage and evolution, the strong
buoyancy and a veering wind profile (albeit modest deep-layer shear)
will favor east-southeastward-spreading convection capable of
damaging wind gusts and isolated hail during the afternoon and again
during the evening/nighttime hours.
...Southeast...
Along the southern periphery of a midlevel anticyclone centered over
the central Appalachians, weak easterly flow through much of the
troposphere will overspread a hot/moist air mass with 3000-4000 J/kg
MLCAPE during the afternoon. Strong to severe pulse thunderstorms
are forecast. The stronger water-loaded wet microbursts will yield
localized gusts of 50-65 mph and be capable of wind damage.
...MT into the northern Great Basin...
Isolated to widely scattered thunderstorms are expected ahead of a
slow-moving midlevel trough moving across the Northwest. Preceding
the trough, around 40 kt of midlevel southwesterly flow and a weakly
unstable air mass will support a couple loosely organized clusters
capable of producing severe wind gusts during the afternoon and
evening. Have extended low-severe probabilities farther south into
ID/NV/UT where inverted-V profiles will support isolated severe
gusts.
..Smith/Dean.. 07/01/2026
Read more CHECK UPDATE ZOOM GRAPHIC
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