443
ACUS11 KWNS 042055
SWOMCD
SPC MCD 042055
NEZ000-COZ000-WYZ000-042300-

Mesoscale Discussion 2136
NWS Storm Prediction Center Norman OK
0355 PM CDT Sat Oct 04 2025

Areas affected...northeast Colorado...southeast Wyoming...and the
Nebraska Panhandle

Concerning...Severe potential...Watch possible

Valid 042055Z - 042300Z

Probability of Watch Issuance...40 percent

SUMMARY...Thunderstorms will increase in coverage and intensity this
afternoon. Isolated severe hail and wind may occur with the
strongest cores. A watch is not anticipated in the short term, but
trends will be monitored.

DISCUSSION...Thunderstorms are developing this afternoon along and
north of a remnant surface boundary stretched along the
Colorado-Wyoming border. These storms appear to be related to weak
warm-air advection between 850 and 700 millibars. This activity is
developing within a weakly unstable atmosphere, with most-unstable
CAPE between 500 and 1000 J/kg, although low-level moisture and
mid-level lapse rates remain rather poor.

Additional thunderstorms will be possible later this afternoon into
the evening as an approaching cold front moves east toward the
region. The cold front should  provide a more focused area for
convective development, and the strongly forced ascent along the
front may support more robust updrafts than currently observed.
These thunderstorms may tap into the strong flow aloft as the core
of mid-level jet streak moves over the region.

The combination of cool temperatures aloft and stronger flow aloft
may support an isolated severe hail or wind gust this evening. A
watch is currently not anticipated in the short term, but conditions
will continue to be monitored and one may be necessary later this
afternoon.

..Marsh/Gleason.. 10/04/2025

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

ATTN...WFO...LBF...BOU...CYS...

LAT...LON   41000498 41710488 42180450 42430367 42370298 42100249
            41690238 40650270 40290345 40200427 40370472 41000498

MOST PROBABLE PEAK WIND GUST...65-80 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN