ACUS11 KWNS 222051
SWOMCD
SPC MCD 222051=20
NDZ000-MTZ000-222215-

Mesoscale Discussion 0498
NWS Storm Prediction Center Norman OK
0351 PM CDT Wed Apr 22 2026

Areas affected...eastern Montana and western North Dakota

Concerning...Severe potential...Watch unlikely=20

Valid 222051Z - 222215Z

Probability of Watch Issuance...20 percent

SUMMARY...High-based storms and clusters could produce isolated
severe gusts into this evening. A WW is unlikely.

DISCUSSION...Afternoon visible imagery showed convective initiation
underway across parts of the northern Rockies and High Plains.
Downstream of a deepening upper low over the Great Basin, strong
ascent was overspreading a modestly moist air mass ahead of a cold
front. Thunderstorm development has been observed through the higher
terrain of central MT and farther east along the cold front.
Additional storm development appears likely into this evening, with
convection gradually intensifying.

Buoyancy is forecast to remain weak with surface dewpoints only in
the upper 30s F. However, very cold mid-level temperatures (-20c)
and steep low-level lapse rates were supporting around 500 J/kg of
MUCAPE, sufficient for occasional strong updrafts. Increasing
southwesterly flow aloft should support a multicellular/cluster
primary storm mode. High LCLs (3-4 km) with steep low-level lapse
rates will promote strong downdrafts and isolated severe gusts with
these storms. Additional clustering is possible should a cold pool
become established. Storms should spread northeastward into this
evening with a risk for severe gusts.

While overall storm intensity and longevity should be limited, some
severe risk is evident into this evening. Severe gust coverage
appears too limited for a convective watch currently, but trends
will be monitored should a more organized cluster evolve.

..Lyons/Mosier.. 04/22/2026

...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!7aJEEF66M2TYaVHTM4K_wmj478JjqqhnoFbUvxlwnYYZ5OUVzPCtaOHhZsJQ3a7PcnrkWXsVe= nXWAhWtnHAt6cJOxig$ for graphic product...

ATTN...WFO...BIS...BYZ...GGW...

LAT...LON 46160423 45740567 45640707 47580780 49030710 49150536
48920377 47850350 47130369 46680383 46160423=20

MOST PROBABLE PEAK WIND GUST...55-70 MPH


=3D =3D =3D
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