ACUS11 KWNS 290043
SWOMCD
SPC MCD 290042=20
MTZ000-IDZ000-ORZ000-WAZ000-290145-

Mesoscale Discussion 0888
NWS Storm Prediction Center Norman OK
0742 PM CDT Thu May 28 2026

Areas affected...central and eastern Washington into the Idaho
Panhandle and northwest Montana

Concerning...Severe Thunderstorm Watch 249...

Valid 290042Z - 290145Z

The severe weather threat for Severe Thunderstorm Watch 249
continues.

SUMMARY...The threat for large hail up to golf-ball size and locally
severe wind gusts continues across the watch area. The potential for
a more widespread damaging-wind event may evolve in the 02-04z time
frame across parts of eastern WA and the northern ID Panhandle,
possibly into far northwest MT, with gusts up to 70-75 mph.

DISCUSSION...Recent visible satellite and radar data indicate robust thunderstorms ongoing across the central ID Panhandle, along and to
the north of a surface boundary where steep lapse rates and
dewpoints in the 50s to around 60 are yielding MLCAPE of 1500-2500+
J/kg. The instability coincides with steadily strengthening
mid/upper-level winds and resultant vertical shear, with the
parameter space supportive of supercell structures capable of large
hail.

Latest model guidance suggests that growing cold pools associated
with the ID convection, and additional strong to severe storms
ongoing across parts of northeast OR may consolidate, leading to a northward-accelerating thunderstorm line in the 02-04z time frame.
The downstream air mass across central and eastern WA has become
quite hot, with a deeply mixed boundary layer and DCAPE values of
1000-1500+ J/kg. Should the scenario unfold as the model guidance
suggests, the ambient thermodynamic environment will favor strong to
intense convective downdrafts capable of wind gusts up to 70-75 mph.

..Mead.. 05/29/2026

...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!8CA_EgG_pQrszqvH0eJjP7q60wFpsBqxV345RSs3FbTxEWzFGbwdanistdta7XDdISUCYSvgm= wPVsnWqjPJdJwcgoj4$ for graphic product...

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

LAT...LON 46001825 45682083 45722150 47192131 48972079 48991398
48001296 47361305 46821264 46491225 46101302 45481415
45221469 45221584 45141626 45301662 45851659 46011690
46001825=20

MOST PROBABLE PEAK WIND GUST...65-80 MPH
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN


=3D =3D =3D
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