RSS Mesoscale Discussions from Storm Prediction Center
No watches are valid as of Thu Apr 23 06:03:01 UTC 2026.
No Mesoscale Discussions are in effect as of Thu Apr 23 06:03:01 UTC 2026.
SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1202 AM CDT Thu Apr 23 2026
Valid 231200Z - 241200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
EASTERN KANSAS...
...SUMMARY...
Severe thunderstorms are expected to develop this afternoon and
evening from the southern and central Plains into the lower to mid
Missouri Valley, and upper Mississippi Valley. Tornadoes, large hail
and severe wind gusts will be possible.
...Southern and Central Plains/Lower to Mid Missouri Valley/Upper
Mississippi Valley...
An upper-level trough will move through the central Rockies this
morning, and into the High Plains this afternoon as a 50 to 60 knot
mid-level jet moves into the Great Plains. At the surface, a cold
front will advance southeastward into the mid Missouri Valley and
central Plains. Moisture advection ahead of the front will increase
surface dewpoints into the mid 60s F by afternoon. This will
contribute to moderate destabilization as surface temperatures warm
along the moist axis. Thunderstorms are first expected to develop
ahead of the front over the mid Missouri and upper Mississippi
Valleys in the early to mid afternoon. Convective coverage will
rapidly expand southward into eastern Kansas by late afternoon, and
into far northern Oklahoma during the early to mid evening. MCS
development appears likely to take place along and ahead of the
front.
The best environment for severe storms will be in eastern Kansas. In
this area, RAP forecast soundings late this afternoon ahead of the
front have MLCAPE peaking just above 3000 J/kg, with 700-500 mb
lapse rates in the 7.5 to 8 C/km range. 0-6 km shear is forecast to
be in the 35 to 40 knot range. This environment will support
supercells with large hail. Hailstones greater than 2 inches in
diameter will be possible with the more intense supercells. In
addition, 0-3 km storm-relative helicity is forecast to increase
into the 300 to 400 m2/s2 range by 00Z, as at 40 to 50 knot
low-level jet strengthens. This will support tornadoes with
supercells. Supercells will initially be discrete but a line is
expected to form by early evening. As the line forms, rotating cells
within the line should also be capable of producing tornadoes. A
strong tornado or two will be possible late this afternoon and early
this evening. A wind-damage threat is also expected to develop. The
southern edge of the line will impact far northern Oklahoma in the
early to mid evening. Convective coverage should be isolated further
south across the rest of Oklahoma.
Further north-northeast into Iowa and southern Minnesota,
instability will not be as strong. RAP forecast soundings by late
afternoon have MLCAPE peaking in the 1500 to 2000 J/kg range. This,
combined with 30 to 35 knots of deep-layer shear and 700-500 mb
lapse rates of 7 to 7.5 C/km should support large hail with
supercells. Supercells and developing line segments should also be
capable of producing wind damage, hail and a tornado or two.
..Broyles/Chalmers.. 04/23/2026
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SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
0100 AM CDT Thu Apr 23 2026
Valid 241200Z - 251200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PARTS OF THE
SOUTHERN PLAINS INTO THE LOWER MISSISSIPPI VALLEY...
...SUMMARY...
Scatteed severe thunderstorms are possible Friday from the Southern
Plains into the Lower Mississippi Valley. Large hail and damaging
winds will be the main hazards, with a brief tornado also possible.
Isolated strong wind gusts may occur across portions of the lower
Ohio Valley as well.
... Synopsis ...
Broad cyclonic flow will persist across much of the central and
western US as a longwave trough remains anchored over the northern
states. In the absences of stronger large-scale ascent across the
southern US, convective evolution will be driven primarily by
remnant boundaries and subtle perturbations within the broader
cyclonic flow.
... Southern Plains into the Lower Mississippi Valley ...
Convection is expected to be ongoing from portions of Oklahoma into
Arkansas and Missouri at the start of the forecast period, largely
tied to a convectively augmented cold front. This activity may still
be capable of producing isolated strong wind gusts early in the
period, but should gradually weaken through the morning as the
low-level jet dissipates and the parent shortwave trough moves away
from the region.
The primary severe threat is expected to develop from afternoon into
the evening along the effective frontal zone and any residual
outflow or differential heating boundaries. Current guidance
suggests the boundary will settle near or south of the I-40
corridor, though some uncertainty in the exact location remains.
Notably, the HRRR is an outlier in maintaining a farther north and
west boundary as compared to other members of the 20260423/00Z HREF.
By afternoon, strong heating south of the boundary will support a
moderately to strongly unstable airmass (SBCAPE values in the
2000-3000 J/kg range) from central/east Texas northward toward the
boundary, with instability gradually decreasing with eastward extent
into Mississippi and Alabama. Deep-layer shear will remain modest
across the region (generally 30-35 knots), supporting organized
multicells and occasional transient supercells.
Thunderstorms should develop/intensify from eastern Oklahoma into
Arkansas along one or more of boundaries across the region. Initial
storms may pose a threat for large hail and localized damaging wind
gusts as low-level shear will generally remain weak. However,
localized enhancements along boundaries or any MCV could support a
brief tornado risk.
With time, storm interactions and consolidating outflows should
support upscale growth into one or more clusters or linear MCS
structures. These systems should move east-southeast into northern
Louisiana and central Mississippi through the afternoon and evening
hours. While the modest deep-layer shear may temper the overall wind
threat somewhat, sufficient organization should still support a
corridor of damaging wind gusts.
Farther west into central and eastern Texas, isolated convection may
occur along a dryline as diurnal heating weakens inhibition to the
east. Storm coverage is expected to remain sparse given weak ascent,
but any sustained updrafts in this strongly unstable environment
could produce large hail.
... Portions of the Ohio Valley ...
A separate corridor of thunderstorms may develop during the
afternoon across portions of the eastern Indiana and western Ohio
in the wake of earlier convection. Modest destabilization should
occur with perhaps up to 1000 J/kg of SBCAPE. Although the low-level
jet will be weakening through the day, residual flow and modest
deep-layer shear may support loosely organized convection capable of
producing damaging wind gusts.
..Marsh.. 04/23/2026
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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1255 AM CDT Thu Apr 23 2026
Valid 231200Z - 241200Z
...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHWEST AND
SOUTHERN AND CENTRAL PLAINS...
...Synopsis...
An upper-level trough and its accompanying mid-level jet streak will
move into the central CONUS today. Simultaneously, a surface trough
and cold front will advance through the central Plains and Upper
Midwest. The most acute fire weather risks are centered over the
central and southern High Plains, specifically behind and ahead of
the cold front. Within this corridor, intense southwesterly winds
will switch to the northwest following the frontal passage. When
coupled with low humidity and exceptionally dry fuels, these factors
will result in Elevated to Critical fire weather conditions.
...Southern and Central Plains...
Wind speeds just off the surface are expected to intensify from
eastern NM into the TX Panhandle by this afternoon, driven by
surface cyclogenesis over southern KS and northwest OK. Given that
the dryline is forecast to remain east of the Caprock through the
morning, moisture recovery will be lackluster across eastern NM and
the western TX Panhandle. With only minimal upper level clouds today
facilitating robust vertical mixing, expect RHs down to 10% or less,
while sustained westerly winds reach 20-25 mph.
The Critical area was expanded to include portions of northeast CO
and southwest NE. At least a few hours of critical conditions are
possible in northwest 15-20 mph winds behind the front before higher
RHs move over the area late in the day. Isolated pockets of
Extremely Critical conditions remain possible within the gap-flow
corridors of southeast CO and other terrain-influenced areas
stretching from eastern CO into the western TX Panhandle. In these
localized areas, sustained winds of 30 mph will likely overlap with
single-digit RHs.
To the north, an Elevated fire weather threat will persist across
the central Plains (including the remainder of eastern CO, western
KS, and much of NE) as dry, post-frontal northwesterly winds benefit
from downslope enhancement. This threat also encompasses portions of
the High Plains where the arrival of dry post-frontal air may cause
existing wildfires or dormant lightning holdovers from Wednesday to
flare up under the sustained dry and breezy regime. Precipitation
accumulation overnight will continue to be closely monitored over
portions of eastern South Dakota where elevated wind/RH conditions
are likely, but fuels are currently expected to become unreceptive.
..Stearns/Williams.. 04/23/2026
...Please see www.spc.noaa.gov/fire for graphic product...
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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
1257 AM CDT Thu Apr 23 2026
Valid 241200Z - 251200Z
...Synopsis...
On Day 2/Friday, upper level ridging across the eastern U.S. will
begin to flatten, transitioning to a fairly zonal flow regime over
much of the southern CONUS. Meanwhile, a large-scale upper trough
will persist over the north-central U.S. along the Canadian border.
Expect very breezy and continued dry conditions through the end of
the work week over the Southwest and southern and central High
Plains.
...Southwest and Southern Plains...
The aforementioned westerly winds aloft will mix down to the surface
during peak heating, leading to strong westerly downslope flow
(sustained at 15-20 mph) and critically low RH (10-15%) that will
overlap very dry fuels on Day 2/Friday. Following several preceding
days of heightened fire weather conditions, the environment will be
further exacerbated across portions of the Southwest and southern
Plains. Winds look to be particularly strong near the Palmer Divide
in east-central CO; this area will be monitored for meeting Critical
thresholds if trends in forecast guidance continue. Increasing
clouds cover later in the day on Day 2/Friday is expected over much
of the region, which will likely work to mitigate some of the fire
weather threat before sunset.
..Stearns/Williams.. 04/23/2026
...Please see www.spc.noaa.gov/fire for graphic product...
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