625
ACUS11 KWNS 091811
SWOMCD
SPC MCD 091810
NEZ000-COZ000-WYZ000-092045-

Mesoscale Discussion 0684
NWS Storm Prediction Center Norman OK
0110 PM CDT Sat May 09 2026

Areas affected...portions of the central High Plains

Concerning...Severe potential...Watch unlikely

Valid 091810Z - 092045Z

Probability of Watch Issuance...20 percent

SUMMARY...High-based thunderstorms will bring a risk for isolated
severe wind gusts and small to perhaps marginally severe hail this
afternoon from southeastern Wyoming into the Nebraska Panhandle and
northeastern Colorado.

DISCUSSION...Latest GOES water vapor imagery depicts a mid-level
shortwave trough embedded within broad northwesterly flow moving
southeastward from southern Montana into northwestern Wyoming.
While low-level moisture remains very limited (dewpoints in the 30s
F), cooling temperatures aloft downstream of this shortwave and
continued insolation are yielding steepening low- and mid-level
lapse rates per latest mesoanalysis. Model forecast soundings
suggest that this will be sufficient for the development of weak
buoyancy (250-500+ J/kg MLCAPE) by early-to-mid afternoon.
Expectation is for ongoing, high-based convection across northern
Wyoming to progress southeastward, with additional development
likely across the high terrain areas of central/southeastern Wyoming
over the next couple of hours.

Despite the aforementioned limited low-level moisture, steep
low-level lapse rates and dry, well-mixed boundary layer profiles
will support the potential for isolated severe wind gusts. 30-40 kts
of effective bulk shear and steep mid-level lapse rates may also
promote some risk for small to perhaps marginally severe hail with
any stronger updrafts. With time, convection will spread
southeastward into the Nebraska Panhandle and northeastern Colorado,
with some potential for upscale growth into linear segments should
cold pools coalesce. Given the forecast limited coverage/magnitude
of the severe threat, watch issuance is unlikely at this time.

..Chalmers/Gleason.. 05/09/2026

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...BOU...CYS...RIW...

LAT...LON   41680678 42020741 42170765 42450766 42810725 43020649
            43130584 43030532 42640451 41910321 41510269 40970269
            40450309 40310397 40880518 41680678

MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN