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DAY3 3/5 RISK AREA POSTED
From
Mike Powell@618:250/6 to
All on Wed Apr 15 08:48:08 2026
ACUS03 KWNS 150729
SWODY3
SPC AC 150728
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0228 AM CDT Wed Apr 15 2026
Valid 171200Z - 181200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF NORTHERN OKLAHOMA AND EASTERN KANSAS...MISSOURI...IOWA...AND FAR
NORTHWEST ILLINOIS...
...SUMMARY...
Widespread severe thunderstorms are expected from parts of the
southern Plains to the Middle and Upper Mississippi Valley vicinity
on Friday and Friday night. All severe hazards will be possible.
...Southern Plains to MS Valley...
A robust upper trough will eject eastward from the northern High
Plains and central Rockies to the Upper Midwest and central Plains
on Friday. As this occurs, strong deep-layer southwesterly flow will
overspread portions of the central/southern Plains to the Mid/Upper
MS Valley and Great Lakes. Flow at 850-700 mb around 40-60 kt will
be common. At the surface, a cold front will extend from northern MN
to a low over eastern NE Friday morning. Meanwhile, a dryline will
extend southwest from the NE low into central KS, northwest OK and
western TX. A warm front initially arcing across central IA into
south-central IL will lift northward through the period ahead of the eastward-advancing surface low tracking across northern IA/southern
MN into WI. A warm sector characterized by mid/upper 60s F dewpoints
will be in place across the southern Plains to the Mid-MS Valley by
midday, with a narrow plume of low 60s F dewpoints extending north
into portions of eastern MN and WI. Steep midlevel lapse rates (7-8
C/km) will overspread this moist boundary layer, resulting in
moderate to strong destabilization.
As strong ascent overspreads the aforementioned surface boundaries
by mid afternoon, widespread thunderstorm development is expected.
While initial supercells are possible given a favorable
thermodynamic environment and supercell vertical wind profiles,
linear forcing along the front combined with strong deep-layer
southwesterly flow parallel to the initiating boundary may result in
rapid upscale development into a QLCS, particularly from northeast
KS/northwest MO into IA. A well-organized line of convection will
pose a damaging wind risk along with possible QLCS tornadoes as
convection develops eastward through the afternoon/evening. If any
discrete supercells develop, an all-hazards risk will also accompany
that activity.
Further south across southern KS into OK, supercell development may
be more probable, at least initially. Convection will initially
develop along the dryline prior to the cold front overtaking this
boundary later in the evening. Any supercells that develop and can
maintain discrete characteristics will pose a risk for very large
hail, strong tornadoes, and damaging winds. With time, the cold
front will overtake the dryline during the evening and move
southeast overnight. Linear convection is expected along the front,
posing a damaging wind and isolated tornado risk during the
nighttime hours.
Capping, weakening large-scale ascent and more modest vertical shear
with southern extent may limit storm potential along the dryline in western/west-central TX.
..Leitman.. 04/15/2026
$$
--- MultiMail/DOS
* Origin: Project Scorpio TEST (618:250/6)
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From
Mike Powell@618:250/6 to
All on Thu Apr 23 08:35:18 2026
ACUS03 KWNS 230728
SWODY3
SPC AC 230727
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0227 AM CDT Thu Apr 23 2026
Valid 251200Z - 261200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF SOUTH-CENTRAL KANSAS INTO CENTRAL AND EASTERN OKLAHOMA AND FAR
NORTHWEST ARKANSAS...
...SUMMARY...
Severe thunderstorms will likely develop across portions of Oklahoma
and Kansas during the evening. These storms will pose a risk of very
large hail, damaging winds, and a couple of tornadoes. Isolated
severe thunderstorms may also develop across portions of North Texas
during the afternoon.
... Synopsis ...
Increasingly diffluent southwest flow will overspread the Southern
and Central Plains on Saturday as the midlevel pattern responds to a
strong shortwave trough/vorticity maximum moving into the Southwest.
This will induce strong southerly winds across the Plains, helping
to quickly draw an old frontal boundary northward. This boundary
should be oriented from northwest to southeast across portions of
Oklahoma by late Saturday.
... Portions of Kansas, Oklahoma, and western Arkansas ...
Most of the day should be devoid of thunderstorms as mid-level
heights rise downstream of a digging trough across the Southwest. At
the same time, strong southerly winds will transport Gulf moisture
northward from the far Southern Plains into the Central Plains.
Diurnal heating of this airmass will result in the development of
strong instability across much of the area, as maximum SBCAPE values
approach 4000 J/kg across portions of north Texas into central Oklahoma.
During the late evening a subtle perturbation within the southwest
flow is forecast to approach Oklahoma. In response to this, the
low-level jet is forecast to increase to between 30 and 40 knots. As
it crosses the northward moving warm front, this warm-air
advection/isentropic ascent will combine with modest large-scale
ascent from the approaching midlevel perturbation to support
scattered thunderstorm develop on the north side of the moisture
gradient. Although differences exist between the various models, the
generic depiction of forecast soundings show long hodographs with
varying degrees of low-level curvature in the presence of 2000-3000
J/kg of MUCAPE. Thus, any storm that develops within the environment
will be capable of producing all hazards initially. With time,
thunderstorms should grow upscale into one or more southeast moving
bowing segments capable of producing damaging winds with perhaps a
QLCS tornado threat.
... North Texas into Southern Oklahoma ...
Diurnal heating of a moist airmass to the east of a dryline will
result in an extremely unstable airmass developing by the afternoon.
Although the region will be devoid of large-scale forcing for
ascent, temperatures in the 90Fs to the west of the dryline may be
sufficient to induce dryline circulations capable of initiating
isolated thunderstorms. Any thunderstorm that develops will be
capable of producing very large hail.
..Marsh.. 04/23/2026
$$
--- MultiMail/DOS
* Origin: Project Scorpio TEST (618:250/6)
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From
Mike Powell@618:250/6 to
All on Fri Apr 24 09:08:44 2026
ACUS03 KWNS 240731
SWODY3
SPC AC 240730
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0230 AM CDT Fri Apr 24 2026
Valid 261200Z - 271200Z
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS SUNDAY EVENING
INTO SUNDAY NIGHT ACROSS MUCH OF KANSAS AND ADJACENT PORTIONS OF
NORTHERN OKLAHOMA...WESTERN MISSOURI...
...SUMMARY...
Widely scattered severe storms with potential to produce large hail
and a couple of strong tornadoes are possible by early Sunday
evening across parts of the central and southern Great Plains,
before one or two organizing clusters of storms spread toward the
middle/lower Missouri Valley with potentially damaging wind gusts.
...Discussion...
A remnant elongated cyclonic mid-level circulation/shear axis may
tend to shift north-northeastward through Saskatchewan/Manitoba
through this period, while larger-scale troughing along an axis
inland of the U.S. Pacific coast through the Hudson Bay vicinity
weakens through this period. However, mid/upper ridging across southern/central Mexico into portions of the southern Great Plains
and lower Mississippi Valley appears likely to maintain considerable
strength, while a notable short wave perturbation accelerates out of
the southern Great Basin/lower Colorado Valley, within strong
southwesterly flow between the two features.
Models suggest that stronger mid-level height falls will generally
overspread the eastern Colorado/western Kansas/southwest Nebraska
vicinity of the high plains late Sunday afternoon into evening,
before reaching southern portions of the middle Missouri Valley by
12Z Monday, accompanied by a developing low within the northern
portion of deepening surface troughing extending southward into the
southern Great Plains. Another low, developing by Sunday afternoon
across the southeastern Colorado/Texas and Oklahoma Panhandle region
may reach portions of central Kansas.
In response to these developments, seasonably moist low-level air,
initially confined to the southern Great Plains, perhaps as far
north as central Oklahoma at the outset of the period, may tend to
advect in a corridor ahead of a sharpening dryline across western
Oklahoma into western Kansas by late afternoon. Downstream, models
suggest that a warm frontal zone may become better defined by early
Sunday evening across southern Kansas into the Ozark Plateau
vicinity, before tending to shift northward.
...Great Plains...
Although though there is not a strong signal yet evident within
latest model output concerning potential convective evolution during
this period, at least isolated to perhaps widely scattered supercell development may initiate along the dryline as far south as northwest
Texas by late Sunday afternoon, in the presence of destabilization
and strengthening shear. By early Sunday evening, this probably
will include enlarging, clockwise curved low-level hodographs
beneath a strengthening southerly low-level jet. This may become
supportive of increasing potential for a couple of strong tornadoes,
in addition to large hail, with increasing storm coverage probable
across the western Kansas vicinity.
Gradually, large-scale forcing for ascent, focusing along the warm
front, may support one or two upscale growing clusters of storms
spreading into the middle/lower Missouri Valley overnight, with
damaging wind gusts becoming the more prominent severe hazard along
with perhaps some continuing risk for tornadoes.
..Kerr.. 04/24/2026
$$
--- MultiMail/DOS
* Origin: Project Scorpio TEST (618:250/6)