175
ACUS11 KWNS 181854
SWOMCD
SPC MCD 181853
WYZ000-UTZ000-IDZ000-182130-

Mesoscale Discussion 2307
NWS Storm Prediction Center Norman OK
0153 PM CDT Fri Sep 18 2026

Areas affected...northern Utah into far southwest Wyoming

Concerning...Severe potential...Watch unlikely

Valid 181853Z - 182130Z

Probability of Watch Issuance...20 percent

SUMMARY...Storms over northern Utah may gradually strengthen, with
hail over 1.00" diameter and locally strong wind gusts expected.

DISCUSSION...An upper low with midlevel cooling continues to move
slowly across northern NV and into southern ID this afternoon.
Meanwhile, surface heating and boundary layer mixing continue within
the surface trough located over eastern NV into UT.

Radar trends indicate that the early day activity may be
transitioning/strengthening coincident with surface heating, with
stronger cores noted. The earlier elongated echoes also appear to be
consolidating into cells.

The steep lapse rate environment, ample moisture and elongated mid
to upper level hodographs should support sporadic severe hail later
this afternoon. Locally severe gusts may also occur as outflows
possibly aggregate and move across northern UT into southwest WY.

..Jewell/Mosier.. 09/18/2026

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

ATTN...WFO...RIW...SLC...PIH...

LAT...LON   40421077 39851176 39851296 39891359 40161377 40271377
            41361311 41841198 42251085 42281022 42040995 41310995
            40991006 40421077

MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN