ACUS02 KWNS 250539
SPC AC 250538
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1238 AM CDT Sun Aug 25 2019
Valid 261200Z - 271200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS
NORTHERN/NORTHEASTERN OK...SOUTHEAST KS...AND WESTERN/NORTHERN MO...
Severe thunderstorms are possible along a cold front from the
southern Plains into the Upper Midwest on Monday.
Cyclonic flow aloft will persist across much of the northern third
of the CONUS on Monday as the mid-latitude cyclone centered over
Manitoba matures. Meanwhile, strengthening westerly flow aloft
throughout its base will spread eastward/southeastward across the
central Plains into the middle MS Valley.
Surface pattern Monday morning will feature a low (associated with
the maturing mid-latitude cyclone) over central Manitoba, with a
cold front extending southeastward to another low near far southwest
KS/OK Panhandle. This cold front is expected to progress
eastward/southeastward throughout the day and overnight, extending
from the Upper Great Lakes southwestward into northwest TX by early
...Southern Plains into the Upper MS Valley...
Air mass ahead of the approaching cold front will likely be
characterized by dewpoints ranging from the low/mid 60s across the
Upper MS Valley to the mid 70s across southeast KS/eastern OK by
late Monday afternoon. This ample low-level moisture coupled with
warm temperatures and steep mid-level lapse rates will result in
strong buoyancy from OK northeastward into MO. Cooler temperatures
will likely limit instability farther north across IA, western IL,
and southern WI.
Even with this variance in instability, thunderstorms are expected
to develop along the length of the front. Highest probability for
severe thunderstorms is expected from north-central OK across
southeast KS/southwest MO into northern MO where the best overlap
between instability and vertical shear exists. Large hail is
expected to be the main severe threat for the first few hours as
strong updrafts develop along the front. Thereafter, upscale growth
will likely lead to strong wind gusts as the primary threat.
...Middle MO Valley...
Showers and thunderstorms will likely be ongoing early Monday
morning across the middle MO Valley as an MCS moves over the region.
Depending on the maturity of this MCS, isolated damaging wind gusts
are possible. However, the current expectation is for the MCS to be
fairly weak by the start of the period, limiting the severe
potential and precluding the need for any probabilities.
...MAXIMUM RISK BY HAZARD...
Tornado: 2% - Marginal
Wind: 15% - Slight
Hail: 15% - Slight