spc ac 080722
day 3 convective outlook
nws storm prediction center norman ok
0222 am cdt mon jun 08 2026
valid 101200z - 111200z
...there is an enhanced risk of severe thunderstorms across portions
of eastern minnesota...much of wisconsin...central and eastern
iowa...and northwest illinois...
...summary...
scattered to numerous severe thunderstorms capable of large to very
large hail, tornadoes, and damaging winds with significant gusts
appear likely across portions of the upper mississippi valley and
midwest wednesday afternoon into night. more sporadic occurrences of
large hail and damaging winds are possible into the central plains.
...synopsis...
the 00z models have trended toward a similarly timed, but slightly
more amplified short-wave trough, which will move through the
northern plains into upper ms valley, in tandem with a 50-60+ kt jet
streak. meanwhile, a stronger upstream system is forecast to amplify
across the northern and central plains late wednesday night into
thursday morning.
at the surface, a cold front initially from the eastern dakotas into
central high plains will push east into the upper great lakes. a
frontal wave is forecast to develop from eastern sd into central mn
by afternoon, where it may link with an outflow boundary extending
into central wi. the trailing extension of the front is expected to
stall across the mid or lower mo valley in response to the deepening
of a surface low over the central or southern high plains.
...upper mississippi valley into upper great lakes and mid/lower
missouri valley...
a very moist boundary layer, characterized by boundary-layer
dewpoints in the upper 60s to mid 70s is forecast ahead of the
front, which coupled with steep lapse rates, will contribute to
moderate to strong instability by afternoon. thunderstorms are
expected to develop by early afternoon along the surface front and
any outflow boundaries across the upper ms valley, with subsequent,
south/southwestward storm development into ia and the lower mo
valley by mid to late afternoon. the strongest deep-layer shear is
forecast across the upper ms valley into upper midwest, with
decreasing bulk-shear magnitudes with southward extent being offset
by stronger instability. the cape/shear parameter space will favor
organized storm modes including supercells and bowing structures.
large to very large hail will likely be the initial hazard, with the
threat for damaging winds and tornadoes increasing as storms move
into wi, eastern ia, and northwest il, where stronger low-level
shear is forecast.
additional, isolated to widely scattered storms are anticipated by
late afternoon into evening across portions of the lower mo valley
into at least eastern ks. while vertical shear will be somewhat
marginal, the strong instability will support strong up/downdrafts
capable of isolated occurrences of large hail and damaging winds.
a separate, elevated thunderstorm regime may materialize wednesday
night into thursday morning across portions central/eastern ne and
northern ks as low-level warm advection increases ahead of the next
mid-level trough moving into the northern and central plains. the
strongest storms will be capable of a large-hail threat.
..mead.. 06/08/2026
click to get wuus03 ptsdy3 product
note: the next day 3 outlook is scheduled by 1930z