ACUS11 KWNS 252346
SWOMCD
SPC MCD 252346=20
MTZ000-IDZ000-ORZ000-260145-

Mesoscale Discussion 0858
NWS Storm Prediction Center Norman OK
0646 PM CDT Mon May 25 2026

Areas affected...portions of the Northern Rockies

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

Valid 252346Z - 260145Z

Probability of Watch Issuance...5 percent

SUMMARY...Potential for isolated damaging to occasionally severe
wind gusts will continue for a few more hours. Watch issuance is not
expected.

DISCUSSION...Isolated high-based convection is ongoing across
portions of the Northern Rockies from central Idaho into western
Montana, with several reports of damaging to severe wind gusts noted
with this activity over the least 1-2 hours. Latest objective
analysis depicts weak buoyancy (250-750 J/kg MLCAPE) across this
region, with a modified 18z BOI observed sounding depicting a deep,
well-mixed boundary layer with an inverted-v thermodynamic profile.
As this convection continues to evolve north-northeastward over the
next couple of hours, it will encounter accelerating mid-level flow
(sampled by the PDT/OTX VAD profiles) ahead of a robust mid/upper
trough digging into the Pacific Northwest. Steep low-level lapse
rates and dry boundary layer profiles will continue to promote
efficient evaporative cooling and downward momentum transport, with
the resultant potential for isolated damaging to occasionally severe
wind gusts.

Latest high-res guidance suggests that some clustering of ongoing
convection along developing cold pools may occur over the next 1-2
hours as storms evolve north-northeastward. In this scenario, a
corridor or two of locally greater severe wind potential may
develop. The greatest potential will likely be across portions of
west-central into northwestern Montana where guidance suggests a
pool of locally greater buoyancy may exist. Watch issuance is not
expected at this time, however, given the isolated nature of the
severe threat.

..Chalmers/Thompson.. 05/25/2026

...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!8pgqA7hNYhqFCu-mbWAEnOXkczAmpDFUuTVlDqtHvR8od3QDF2JEQ_XNjz6CrN5lvevDcV8Sn= 99fBNfJd1mioQAmemk$ for graphic product...

ATTN...WFO...TFX...PIH...MSO...BOI...OTX...PDT...

LAT...LON 44791682 45951684 46601667 47491617 48281562 48931515
49041496 49061366 49071265 49061197 48811185 48041166
47421166 46541177 45331213 44631243 44371302 44261377
44131483 44161600 44351653 44791682=20

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


=3D =3D =3D
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