Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1256 AM CDT Sun Aug 25 2024
Valid 251200Z - 261200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR THE EASTERN
DAKOTAS INTO WESTERN/NORTHERN MN...
...SUMMARY...
Scattered severe storms may develop across the northern Plains this
afternoon and evening, with more isolated severe potential from the
High Plains into the Four Corners vicinity. A couple of
strong/marginally severe storms may also occur across parts of Ohio
and lower Michigan.
...Synopsis...
The southern portion of a persistent upper-level trough over the
West will move slowly eastward today, as an embedded mid/upper
cyclone moves slowly northeastward over the Great Basin. An
upper-level trough will persist over the northeast CONUS, to the
south of a weak mid/upper cyclone over Quebec. At the surface, the
southern extension of a cold front across the Canadian Prairies will
move into the Northern Plains, with a weak surface cyclone
potentially developing near the NE/SD border.
...Central/eastern Dakotas into Minnesota
Strong instability is forecast by afternoon along/ahead of the cold
front from the central/eastern Dakotas into Minnesota, with
sufficient effective shear (generally 30-40 kt) for some storm
organization. However, with some capping and generally modest
large-scale ascent, details regarding storm development during the
afternoon/evening remain somewhat uncertain.
In general, at least isolated development will be possible near the
front across the eastern Dakotas into northwest MN. There will be
some supercell potential with initial development, with an attendant
threat of hail, damaging wind, and possibly a tornado. Depending on
the extent of storm coverage, some upscale growth into clusters with
an increasing damaging-wind threat will be possible by evening.
There is also some signal for elevated convection across parts of
the region later tonight, which could pose a severe threat in the
presence of large MUCAPE.
...Four Corners region into Wyoming and the adjacent High Plains...
Some organized severe potential is evident from the Four Corners
region into eastern UT/western CO this afternoon, as the mid/upper
cyclone and related shortwave trough over the Great Basin begin to
impinge on the western periphery of the midlevel moist plume. With
scattered to numerous storms expected for much of the day, the
magnitude of destabilization remains uncertain. However, sufficient
deep-layer shear will support potential for marginal supercells and
a few stronger clusters capable of strong to severe gusts and
isolated hail.
Farther east into parts of the High Plains, isolated storms will be
possible during the afternoon/evening, though coverage and
organization may tend to be limited by weak large-scale ascent and
only weak to marginal deep-layer shear. Isolated strong to severe
gusts will be possible within the well-mixed environment across the
region.
...Parts of OH/lower MI...
Showers and isolated thunderstorms may develop this afternoon across
parts of OH and lower MI, in conjunction with diurnal heating.
Guidance continues to vary considerably regarding instability and
the coverage/intensity of convection across the region. However.
steepening low-level lapse rates and modest northwesterly flow aloft
could support gusty-wind and small-hail potential with any stronger
storms.
..Dean/Elliott.. 08/25/2024
Read more CHECK UPDATE ZOOM GRAPHIC
http://dlvr.it/TCLWJx
