RSS Mesoscale Discussions from Storm Prediction Center
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1246 AM CDT Tue Jul 07 2026
Valid 071200Z - 081200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE NORTHERN
HIGH PLAINS INTO THE UPPER MIDWEST...
...SUMMARY...
Widely scattered to scattered severe storms capable of large hail
and severe wind gusts are possible from the northern High Plains
into parts of the Upper Midwest Tuesday into Tuesday night. Isolated
severe storms capable of mainly damaging wind gusts are possible
Tuesday afternoon and evening from the southern Mid-Atlantic into
the Carolinas, the Sabine River Valley, and parts of the Great
Basin.
...Synopsis...
Ahead of a shortwave trough moving from the northern Rockies into
the northern High Plains, the models indicate a lead disturbance
(possible MCV) and associated belt of enhanced mid-level flow
progressing through ND into northern MN on Tuesday. Elsewhere, a
shortwave trough will move through the Northeast, while a mid-level
low lingers over the Mid South/lower MS Valley.
At the surface, the primary feature of interest is a front that is
expected to become quasi-stationary from western SD through central
or southern MN and northern WI by afternoon. A surface low is
projected to develop along the boundary in western SD with a lee
trough trailing south from that feature into the central High
Plains.
...Northern High Plains into the Upper Midwest...
Clusters of elevated thunderstorms tied to the lead disturbance may
be ongoing at 12Z Tuesday across portions of eastern MT and western
ND, to the north of the surface front. Modest instability and some
vertical-shear enhancement may support an isolated large hail threat
through the morning, mainly in southern ND.
In the wake of the early-day storms, low-level, upslope flow will
strengthen across the northern High Plains in response to the
approach of a shortwave trough from the west. The associated
increase in low-level moisture will coincide with a plume of steep
mid-level lapse rates to yield MLCAPE up to 1000-2000 J/kg from
central MT into western SD with upwards of 2000-3500 J/kg farther
east along the front in SD and MN.
Widely scattered thunderstorms are expected to develop by mid to
late afternoon within the upslope regime from central into eastern
MT and along the front across SD and perhaps MN. Sufficiently strong
vertical shear is forecast from MT east along the front in SD to
support supercell storm modes with an associated risk for large hail
and damaging winds. The 00Z CAMs indicate the initial discrete
storms merging into clusters or one or more MCSs Tuesday evening
into night along a nocturnally strengthening low-level jet. Severe
wind gusts will become the predominant hazard with that mode
transition.
Additional storms are possible near and west of the lee trough in
southeast WY, northeast CO, and the NE Panhandle during the
afternoon into evening. The local environment will feature a deep
and well-mixed boundary layer, which will support the potential for
a few severe wind gusts and perhaps some hail.
...Southern Mid-Atlantic into the Carolinas...
A moist and moderately unstable air mass is expected to support
scattered thunderstorm development by early to mid afternoon from
the Blue Ridge Mountains east to the lee trough and Carolina sea
breeze. Vertical shear will remain weak, which will limit the
potential for storm organization. Nonetheless, the presence of steep
low-level lapse rates will enhance downdraft potential, leading to
the risk for sporadic damaging wind occurrences, especially with any
storm clusters.
...East Texas into the Sabine River Valley...
A weak vorticity lobe is forecast to pivot south through the Ozark
Plateau into the ArkLaTex on Tuesday with a preceding zone of
forcing for ascent acting on a very moist and moderately unstable
air mass. A resultant increase in storm coverage is expected through
the afternoon with some CAM signal for a loosely organized cold pool
to evolve, which will support the potential for sporadic damaging
wind gusts.
...Great Basin...
The 00Z models suggest that a weak mid-level disturbance will move
through northeast NV and northern UT Tuesday afternoon into the
evening, enhancing lift and vertical shear to some extent. Isolated
to widely scattered thunderstorms are expected to develop ahead of
that feature by mid to late afternoon atop a deep and well-mixed
boundary layer, which will be supportive of locally severe wind
gusts.
..Mead/Moore.. 07/07/2026
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SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1230 AM CDT Tue Jul 07 2026
Valid 081200Z - 091200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS WEDNESDAY
AFTERNOON INTO WEDNESDAY NIGHT ACROSS PARTS OF THE CENTRAL GREAT
PLAINS AND UPPER MIDWEST...
...SUMMARY...
Clusters of strong thunderstorms with potential to produce severe
hail and wind may evolve across parts of the Upper Midwest into
central Great Plains Wednesday through Wednesday night.
...Discussion...
While a blocking, but perhaps weakening, mid-level high lingers in
the north central Canadian Arctic latitudes, it appears that one
still fairly vigorous short wave trough and embedded low will begin
to dig southeast of the Hudson Bay vicinity Wednesday through
Wednesday night, while an upstream short wave trough pivots across
the Canadian Rockies, then northward toward the Northwest
Territories. In association with these developments, within a belt
of modest westerlies closer to and south of the international
border, subtle mid-level ridging may overspread the northern
Rockies, with similar amplitude downstream troughing digging across
the northern Great Plains, Upper Midwest and Great Lakes region.
Beneath this regime, a weak cold front, perhaps reinforced by
convective outflow in some locations, is forecast to overspread much
of the remainder of the Upper Midwest/adjacent Great Lakes and
middle Missouri Valley vicinity by late Wednesday night. This may
be preceded across parts of the central Great Plains by conglomerate
convective outflow emanating from considerable thunderstorm
development spreading off the Laramie Range/Front Range vicinity,
within weak west-northwesterly steering flow.
In the southern mid- to subtropical latitudes, modest mid-level
ridging is forecast to generally prevail, but weak remnant troughing
may slowly migrate from the Mid South toward the southern
Appalachians, along its northern periphery.
...Upper Midwest...
Steeper mid-level lapse rates associated with a remnant plume of
elevated mixed-layer air may become increasingly confined to the
higher plains during this period. However, seasonably high moisture
content along/ahead of the southward advancing cold front may still
become supportive of mixed-layer CAPE of 1500-2000+ J/kg with
daytime heating.
Based on latest guidance, it is appearing less probable that a
cluster of strong continuing thunderstorm development, with a
possible MCV, will be substantively maintained into this period
across parts of the Upper Midwest into adjacent Great Lakes region.
But, this remains uncertain.
There appears a stronger signal for renewed thunderstorm development
within the corridor of pre-frontal destabilization trailing to the
southwest, across central into southern Wisconsin, southeastern
Minnesota and northeastern Iowa by late Wednesday afternoon, aided
by forcing for ascent with the digging mid-level troughing.
It is possible that a belt of convectively augmented westerly
mid-level flow, including 30+ kt around 700 mb, contributes to
sufficient shear for evolving supercell structures. These may pose
a risk for severe hail, and perhaps some potential for a tornado or
two, before damaging wind gusts become more prominent prior to storm
weakening Wednesday evening.
...Central Great Plains...
By late Wednesday afternoon or early evening, it appears that
boundary-layer destabilization associated with moistening easterly
low-level flow may support intensification of initially scattered
thunderstorm development off the Laramie Mountains through Colorado
Front Range. Pronounced veering of wind fields with height may
yield sufficient shear for supercells posing a risk for severe hail
and wind.
There remains a fairly notable signal that forcing associated with a
nocturnally strengthening low-level jet, and perhaps a subtle
digging mid-level perturbation, may contribute to an upscale growing
and organizing cluster with potential to produce more widespread
strong to severe wind gusts Wednesday evening into Wednesday night.
...Parts of the southern Mid Atlantic...
Thermodynamic profiles may again become conducive to locally strong
downbursts in convection likely to develop off the Blue Ridge
Mountains, and within surface troughing to the north and northeast
of a weak developing lee surface low. Aided by forcing for ascent
associated with weak low-level warm advection and convergence, an
upscale growing cluster, with potential to produce potentially
damaging wind gusts along the leading edge of consolidating outflow,
could overspread the North Carolina Piedmont by Wednesday evening.
..Kerr.. 07/07/2026
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