791
ACUS01 KWNS 082002
SWODY1
SPC AC 082000

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0300 PM CDT Sat Jun 08 2024

Valid 082000Z - 091200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
EASTERN COLORADO INTO WESTERN/CENTRAL KANSAS...

...SUMMARY...
Severe thunderstorms are expected to develop across the central High
Plains this afternoon, and then spread toward central Kansas this
evening. Significant severe winds up to 75-85 mph will likely be the
main threat with this activity, but isolated very large hail is also
possible. Scattered severe thunderstorms may also occur across parts
of Missouri and vicinity late this afternoon and evening.

...20z Update...
Thunderstorm activity has begun across the central High Plains this
afternoon. The Marginal and Slight Risk areas were expanded slightly
further west into the Denver metro and vicinity to account for
latest trends in thunderstorm development and potential for damaging
winds and hail.

Thunderstorms are expected to continue to increase in coverage
across the central High Plains and central Plains through the
afternoon. Mode is expected to become linear downstream, with
potential for bowing segments capable of potentially significant
winds up to 75-85 mph. Adjustments were made to bring the Slight
Risk further south into northern Oklahoma and to expand the Marginal
risk in northern Oklahoma and northern Kansas, given uncertainty in
the evolution of the potential MCS. A very unstable air mass is
progged to be in place across northern Oklahoma, which may support
further southward development along the southern flank of the
eastward moving MCS late tonight. Otherwise, the Enhanced area
remains unchanged with this outlook.

..Thornton/Goss.. 06/08/2024

.PREV DISCUSSION... /ISSUED 1122 AM CDT Sat Jun 08 2024/

...Central Plains...
Latest surface observations show a front draped from the central
High Plains into southern KS/northern OK. Modest low-level upslope
flow across eastern CO acting in tandem with an approaching
shortwave trough over the Great Basin will likely support convective
development by early afternoon over the higher terrain of the
central Rockies/Front Range. Steep mid-level lapse rates and robust
daytime heating of a moist low-level airmass downstream will foster
moderate instability along/north of the front from eastern CO into
western/central KS.

Current expectations are for thunderstorms to quickly become severe,
with 35-45 kt of deep-layer shear fostering updraft organization and
some threat for supercells initially. Large to very large hail will
be a risk with this more discrete convection. But, upscale growth
into an intense bowing cluster appears likely across parts of far
eastern CO into western/central KS by late afternoon/early evening
as a low-level jet gradually strengthens. Numerous severe wind
gusts, some potentially significant (up to 75-85 mph), should occur
with this bow through at least late evening as it moves quickly
eastward over KS. Latest guidance continues to show the greatest
large hail and severe wind threat in/near the Enhanced Risk, so only
small expansions have been made to the greater wind probabilities in
southwest/central KS with this update.

...Missouri and Vicinity...
A compact MCV is evident on visible satellite imagery over the
Mid-South/lower OH Valley late this morning. This feature will
continue moving quickly eastward today across the OH/TN Valleys. In
its wake, a rather moist and gradually destabilizing low-level
airmass will be present over MO and vicinity. While forcing aloft
appears nebulous over this region, most guidance shows scattered
thunderstorms developing by late afternoon or early evening across
southern/central MO in a moderately to strongly unstable environment
with somewhat enhanced west-northwesterly mid-level flow. Any
convection that can develop and be sustained would pose a threat for
large hail, damaging winds, and perhaps a tornado or two through the
evening. Given latest guidance trends, have made a small expansion
to the Slight Risk in southern MO.

...Oregon...
Isolated strong to severe wind gusts may occur with any convection
that can develop over the Cascades in southern OR late this
afternoon and subsequently spread eastward through early evening.
With neutral to slightly rising mid-level heights, overall coverage
of robust thunderstorms should tend to remain limited.

$$