Storm Prediction Center Mesoscale Discussion 2307

   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