089
ACUS02 KWNS 260611
SWODY2
SPC AC 260609

Day 2 Convective Outlook CORR 1
NWS Storm Prediction Center Norman OK
0109 AM CDT Wed Jun 26 2024

Valid 271200Z - 281200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM
CENTRAL/EASTERN MT INTO THE NORTHERN/CENTRAL GREAT PLAINS...

CORRECTED FOR TORNADO NDFD GRID

...SUMMARY...
Severe thunderstorms are possible across parts of Montana into the
northern and central Plains on Thursday.

...Northern Rockies into the northern/central High Plains...
A seasonably strong mid/upper-level shortwave trough is forecast to
move from the Northwest across the northern Rockies during the day
on Thursday, and into northern High Plains by Thursday night. A
surface low is forecast to deepen across southeast MT during the
day, and then move east-southeastward toward western/central SD.
Low-level southeasterly flow will support moisture return into
eastern MT and the western Dakotas.

Moderate to locally strong buoyancy may develop by late afternoon
across the western Dakotas into eastern MT, with somewhat more
modest destabilization possible farther west into central MT. Strong
to severe storms could develop relatively early in the day from
southwest into central MT. This early convection could spread
eastward and intensify through the day, with additional development
possible farther east into eastern MT and the western Dakotas.
Increasing mid/upper-level flow will support supercell potential.
Large to very large hail and severe gusts (possibly in excess of 75
mph) will be possible, along with some threat for a tornado or two.
Some upscale growth may occur during the evening, with some severe
threat potentially persisting Thursday night as storms move eastward
across the Dakotas.

If model trends favor the currently more aggressive guidance
regarding low-level moisture and destabilization across MT into the
western Dakotas, then probabilities may eventually need to be
increased for all hazards.

...Central Plains...
Elevated convection and possibly a remnant MCS may be ongoing
Thursday morning across parts of the central Plains. In the wake of
the morning convection, a surface boundary is expected to move
northeastward as a warm front, aided by a moderate southerly
low-level jet. Isolated to widely scattered storm development is
expected by late afternoon, both near a diffuse dryline, and also
potentially near any remnant outflow boundaries from morning
convection.

Midlevel flow will be weaker with southward extent, but deep-layer
shear will still be sufficient for some storm organization within a
moderately buoyant environment. A mixture of cells and clusters is
expected, including potential for a few supercells with a threat of
hail and severe gusts. Any supercell that persists from late
afternoon into the early evening could also pose some tornado
threat, within a regime of increasing low-level flow/shear.

Upscale growth into multiple clusters or possibly an MCS will be
possible Thursday evening/night, as a low-level jet nocturnally
increases. Any such cluster/MCS could spread some severe threat
across central and potentially eastern KS/NE.

...Eastern UT/western CO and vicinity...
Weak to moderate buoyancy may develop from eastern UT into western
CO during the afternoon, within a relatively moist environment. The
southern fringe of strong westerly flow aloft will spread across the
region, providing sufficient deep-layer shear for at least modestly
organized storms. Isolated severe wind and hail may occur with the
strongest storms within this regime.

...Carolinas into Georgia...
Moderate destabilization is forecast Thursday along/ahead of a cold
front that is currently expected to be draped from south GA into
parts of the Carolinas. A weak upper-level trough is expected to be
in place over the region, and scattered thunderstorms may develop
during the afternoon into the early evening. Guidance varies
somewhat regarding the strength of deep-layer shear across the
region, but at least isolated damaging wind could accompany the
strongest storms during the afternoon and early evening.

..Dean.. 06/26/2024

$$