ACUS03 KWNS 150732
SWODY3
SPC AC 150731

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0231 AM CDT Fri May 15 2026

Valid 171200Z - 181200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE CENTRAL PLAINS INTO THE UPPER MIDWEST...

...SUMMARY...
Severe storms will be likely Sunday from portions of the central and
southern High Plains into the Upper Midwest. Supercells capable of
all hazards will be possible before upscale growth and an emerging
damaging wind risk continues into the evening.

...Synopsis...
An upper-level trough will begin to eject across the Intermountain
West on D3/Sunday with a more subtle shortwave trough moving across
the central Plains. As a result, deepening low pressure will develop
across eastern Colorado/western Kansas with strengthening southerly
flow and warm moist advection south of a warm front lifting
northward into the northern Plains and upper Midwest. Early in the
period, elevated storms will likely be ongoing across portions of
Iowa into southern Minnesota. Scattered severe storms capable of all
hazards will be expected to develop near the warm front/low across
eastern Colorado into Nebraska and across southern South Dakota
continuing into portions of the upper-Midwest along the cold front
through the evening. A more isolated and conditional threat for
severe storms will extend southward along the dryline from western
Kansas into western Oklahoma.

...Central Plains into the Upper Midwest...

Early day elevated convection is expected to move across portions of
Iowa into the upper-Midwest. This will pose some risk for severe
hail through the morning. Across the central Plains, strong daytime
heating is expected to yield moderate to strong instability across
much of the central Plains. This in combination with strong deep
layer shear suggests a rather volatile environment, particularly
across central Nebraska into southern South Dakota/northwestern
Iowa. Guidance suggests that thunderstorms will develop across
eastern Colorado into Nebraska by the afternoon. Initial
thunderstorm development will likely be supercellular and capable of
all hazards including large to very large hail, damaging wind, and
tornadoes. As the front sags southward through the evening, eventual
upscale growth into a squall line is expected by the evening. A
strong 50 kt low-level jet will ramp up into the evening, which may
support a continuing potential for tornadoes, some of which may be strong.

...Western Kansas into western Oklahoma...

A more conditional threat may extend southward along the dryline
into western Kansas and western Oklahoma. Guidance suggests some
signal for isolated supercells to develop along and east of the
dryline Sunday afternoon. The environment here will conditionally
favor large to very large hail, damaging wind, and perhaps a tornado
or two with the strengthening low-level jet in the evening.

..Thornton.. 05/15/2026

$$
--- SBBSecho 3.28-Linux
* Origin: Capitol City Online (618:250/10)

ACUS03 KWNS 160737
SWODY3
SPC AC 160736

Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0236 AM CDT Sat May 16 2026

Valid 181200Z - 191200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE SOUTHERN/CENTRAL PLAINS INTO THE MIDWEST...

...SUMMARY...
Numerous strong thunderstorms are expected to develop Monday along a
cold front and dryline extending from the Great Lakes into the
central/southern Plains. Supercells capable of all hazards
(including very large hail and strong to intense tornadoes) will be
possible across central Kansas into southeastern Nebraska.

...Synopsis...
On Monday, the western trough will take on a negative tilt before
ejecting across the central Plains, with strong southwesterly flow
aloft overspreading the region. As a result, a strong surface low
will development across western Kansas. A surface cold front will
extend northward to a secondary surface low across the upper
Midwest. A dryline will extend southward across portions of western
Kansas into western Oklahoma. Numerous thunderstorms are expected to
develop along and ahead of the cold front and further south along
the dryline Monday afternoon and evening from Nebraska into central Kansas.

...Central Kansas into southeastern Nebraska...

A volatile environment is expected to be in place ahead of the
dryline across central Kansas Monday afternoon, with moderate to
strong instability, strong deep layer shear, and steep low to
mid-level lapse rates. This will favor supercells as the primary
mode with developing thunderstorms along the dryline in the
afternoon, with potential for large to very large hail (some 2-4
inch). Through the afternoon and evening, a 40-50 kt southerly low
level jet will shift into central Kansas with large clockwise
enhancement of low-level hodographs. Should the mode be able to
remain discrete supercells, strong to intense tornadoes will be
possible across central Kansas into southeastern Nebraska. This in
combination with potential for very large hail may warrant higher
probabilities as mesoscale details become clearer.

As the front shifts southward through time, upscale growth will be
favored with increasing probabilities for damaging winds.

...Iowa into Wisconsin and the Great Lakes Region...

Widely scattered thunderstorm development is expected further north
along the front into Iowa/Wisconsin and north into the Great Lakes
Region. Early day convection may be ongoing at the start of the
period within these regions, which may limit how much
destabilization can occur before the afternoon. Nonetheless,
guidance suggests potential for damaging wind and perhaps a few
instances of severe hail with storms along the front Monday
afternoon and evening.

...Western Oklahoma into northern Texas...

Forcing for ascent will be weaker across the dryline into western
Oklahoma and northern Texas. Guidance does suggest that a few
isolated supercells could develop near the dryline, with potential
for large to very large hail, damaging winds, and perhaps a tornado.
Given the strong flow aloft and better large scale ascent will
reside further north in Kansas, mode may quickly become messy with
uncertainty in overall coverage at this time.

..Thornton.. 05/16/2026

$$
--- SBBSecho 3.28-Linux
* Origin: Capitol City Online (618:250/10)