SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook CORR 1
NWS Storm Prediction Center Norman OK
1222 PM CDT Sat Aug 09 2025
Valid 101200Z - 111200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SUNDAY THROUGH
SUNDAY NIGHT ACROSS PARTS OF THE SOUTHERN ROCKIES AND CENTRAL GREAT
PLAINS INTO LOWER MISSOURI VALLEY...
CORRECTED TORNADO PROBABILITY GRAPHIC
...SUMMARY...
Isolated to widely scattered strong thunderstorms may impact a
corridor from the southern Rockies into the lower Missouri Valley
Sunday through Sunday night, accompanied by a risk for potentially
damaging wind gusts and some hail.
...Discussion...
Models indicate that mid/upper ridging will remain generally
prominent across the subtropical through mid-latitudes of the
western Atlantic through eastern Pacific. Between a pair of
relative centers of higher heights, offshore of the Atlantic and
Pacific coasts, a notable mid-level low, initially centered near the
central Canadian/U.S. border vicinity, is forecast to transition to
an open wave and accelerate across northwestern Ontario through
northern Quebec Sunday through Sunday night. This is likely to be
trailed by a short wave trough digging east southeast of the
Canadian Rockies, through the Canadian Prairies.
South of the international border, weak cyclonic flow is forecast to
linger between the ridging, across the Rockies through Great Plains
and upper Mississippi Valley into upper Great Lakes region. One
embedded short wave perturbation may gradually turn east of the
Colorado Rockies through central Great Plains, perhaps preceded by
one or two convectively generated or augmented perturbations across
parts of the lower Missouri Valley toward Upper Midwest/Great Lakes
vicinity.
Near/beneath the southern periphery of this regime, it appears that
the remnants of an initially broad plume of warm, elevated
mixed-layer air advecting to the east of the Rockies will continue
to become suppressed south/southwestward across the lower Missouri
Valley and south central Great Plains. However, associated
relatively dry lower/mid-tropospheric profiles with at least
modestly steep lapse rates may still contribute to sizable CAPE, and
an environment potentially conducive to downbursts and substantive
surface cold pools in convective development. This should be
maximized where seasonably high boundary-layer moisture content
persists, in the wake of a stalled to slowly southward advancing
convectively reinforced cold front across the central Great Plains,
and either side of it across the lower Missouri Valley.
...Southern Rockies into lower Missouri Valley...
Sub-synoptic developments still characterized by relatively low
predictability, including potential convective evolution today into
early Sunday, may considerably influence the convective potential
for Sunday through Sunday night. The potentially focusing surface
front and associated corridor of destabilization may be most
impacted, with the environment otherwise likely to be rather
marginal for organized severe thunderstorm development, in the
presence of modest forcing for ascent and weak deep-layer mean
flow/shear. But, the evolution of one or two thunderstorm clusters
with potential to produce swaths of strong to severe gusts does not
appear out of the question, particularly to the lee of the Front
Range/Sangre de Cristo Mountains into the central Great Plains late
Sunday into Sunday night, aided by the most notable short wave
impulse and, perhaps, a nocturnally strengthening southerly
low-level jet.
..Kerr.. 08/09/2025
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