Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0307 PM CDT Tue Jun 23 2026
Valid 232000Z - 241200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE CENTRAL HIGH PLAINS AND COLORADO FRONT RANGE...
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL
AND SOUTHERN PLAINS...MID-ATLANTIC STATES...AND UPPER MIDWEST...
...SUMMARY...
Severe thunderstorms capable of producing 2+ inch diameter hail, 75+
mph gusts, and isolated tornadoes are expected from the central High
Plains into parts of the southern Plains through tonight. Other
severe thunderstorms are expected across southeast Virginia and
eastern North Carolina, as well across the Upper Midwest.
...20Z Update...
The primary change with this update was a westward expansion of
severe probabilities (including the ENH) toward the higher terrain
in southern/central CO. Rich boundary-layer moisture (middle/upper
60s dewpoints) along the western edge of convectively reinforced
outflow in the central High Plains will spread westward beneath
steep midlevel lapse rates toward the higher terrain through this
afternoon into tonight -- in response to a passing midlevel wave to
the north. This rich moisture/outflow and enhanced easterly upslope
flow should support isolated to widely scattered thunderstorms along
the higher terrain into this evening. Around 50 kt of effective
shear and strong surface-based buoyancy will promote supercells
capable of producing very large hail along the I-25 corridor.
Elsewhere, only minor modifications were made to the outlook, to
include trimming severe probabilities behind eastward-spreading
convection in the Mid-Atlantic, and a southward expansion of
probabilities in the southern Plains (ahead of southward-moving
thunderstorm clusters).
..Weinman.. 06/23/2026
.PREV DISCUSSION... /ISSUED 1145 AM CDT Tue Jun 23 2026/
...Southern Plains and Central High Plains...
Complex scenario exist with multiple iterations of convective
clusters ongoing regionally at midday, including a relatively more
intense/focused cluster near the southwest Oklahoma and eastern
Texas Panhandle border vicinity. These storms are likely to persist
generally south-southeastward today, and potentially grow upscale
with continued wind/hail potential, but details are complicated by
prevalent outflow/cloud debris etc. Additional development may occur
later today into tonight on the west-northwest fringe of these early
day storms/residual outflows and near the front/east of the surface
low, which could bring about a renewed severe potential mainly in
the form of large hail and damaging winds. However, recent HRRR runs
(14z/15z) have notably trended much more limited with this
late-day/evening redevelopment scenario.
Farther west/north, weak low-level upslope flow and a small-scale
mid-level perturbation embedded within the westerly flow aloft
should encourage at least isolated convective development across
southeast Wyoming into eastern Colorado by late afternoon, and more
so, into early/mid evening. A conditionally favorable environment
for very large hail will exist across the central High Plains this
afternoon into tonight. Any thunderstorms that can develop will
likely become severe given strong deep-layer shear, the presence of
steep mid-level lapse rates, and moderate to locally strong
instability. Even though low-level flow and shear will remain modest
this evening across the central High Plains, a tornado may still
occur with any sustained supercell.
...Southeast Virginia/Eastern North Carolina...
Within large-scale upper troughing over the eastern CONUS/Canada, an
embedded mid-level shortwave trough will move eastward today across
the Carolinas and southern Mid-Atlantic. At the surface, a cold
front will also develop eastward across these areas through the
afternoon. Thunderstorms will increase through early/mid afternoon
along and ahead of the front. While lapse rates aloft will remain
poor, sufficient instability will exist with daytime heating to
support surface-based convection. A generally linear/cluster mode is
anticipated given the frontal forcing, with modestly enhanced and
increasing low/mid-level flow and related shear supporting
thunderstorm organization. Scattered damaging winds appear to be the
main threat with this activity as it spreads eastward through the
afternoon, with the greatest concentration forecast across parts of
southeast Virginia and eastern North Carolina. A brief tornado or
two may also occur.
...Northern Plains/Upper Midwest...
A closed mid-level low over south-central Canada this morning will
move slowly eastward today. A belt of enhanced (40-50 kt) westerly
mid-level winds will overspread parts of the northern Plains and
Upper Midwest to the south of this low. At the surface, a cold front
in the process of occluding is located over the Dakotas.
Thunderstorms should develop this afternoon along/east of this
boundary across parts of the eastern Dakotas into western Minnesota.
Given sufficient deep-layer shear and instability, some of this
activity is expected to pose a severe hail/wind risk, along with the
potential for a couple of tornadoes in immediate proximity of the
surface boundary where low-level CAPE/shear will be maximized.
...Coastal Southeast...
Isolated severe thunderstorms mainly capable of downbursts/wind
damage will be possible this afternoon within a moist and unstable
airmass for areas including far southern Georgia and northern
Florida.
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