ACUS11 KWNS 121847
SWOMCD
SPC MCD 121847
UTZ000-NVZ000-122045-

Mesoscale Discussion 1885
NWS Storm Prediction Center Norman OK
0147 PM CDT Mon Aug 12 2024

Areas affected...southern portions of the southern Great Salt Lake
Desert into Greater Salt Lake City vicinity

Concerning...Severe potential...Watch unlikely

Valid 121847Z - 122045Z

Probability of Watch Issuance...5 percent

SUMMARY...Thunderstorm development may continue to increase, with
some consolidation possible, across southern portions of the Great
Lake Lake Desert into southern Salt Lake City vicinity through 3-4
PM MDT.  This activity may be accompanied by small hail and a few
strong to severe surface gusts.

DISCUSSION...A moist boundary layer, including surface dew points in
the mid 50s F, has become moderately unstable with CAPE increasing
in excess of 1000 J/kg with daytime heating.  This has already
supported the initiation of a number of thunderstorms, perhaps aided
by forcing for ascent associated with a weak short wave impulse,
preceding a notable mid-level trough progressing inland across
northern and central California through late afternoon.

Daytime heating has already contributed to a mixed boundary layer
characterized by temperature/dew point spreads up to around 30 F,
but this may not increase much further, as convection becomes
increasingly widespread through 21-22Z.  Despite the somewhat modest
depth of the boundary layer, shear beneath 30-50 kt
west-southwesterly flow in the 500-300 mb layer may contribute to
small to perhaps marginally severe hail in stronger storms.  And
melting/sub-cloud evaporative cooling might still contribute to
outflow with strong to locally severe surface gusts reaching the
surface, aided by modest east-northeasterly storm motions within
25-30 kt cloud-bearing layer mean flow.

..Kerr/Mosier.. 08/12/2024

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

ATTN...WFO...SLC...LKN...

LAT...LON   40211407 41041198 40241180 39791231 39141442 40211407