393
ACUS11 KWNS 210437
SWOMCD
SPC MCD 210437
IAZ000-MNZ000-NEZ000-SDZ000-210600-

Mesoscale Discussion 1351
NWS Storm Prediction Center Norman OK
1137 PM CDT Thu Jun 20 2024

Areas affected...northeastern Nebraska...southeastern South Dakota

Concerning...Severe Thunderstorm Watch 440...

Valid 210437Z - 210600Z

The severe weather threat for Severe Thunderstorm Watch 440
continues.

SUMMARY...While thunderstorm development is likely to continue
across the region overnight, the risk for severe weather is expected
to remain limited and a new severe weather watch is not currently
anticipated.

DISCUSSION...With the approach of the weakening upstream cluster of
storms and associated cold pool, the persistent, quasi-stationary
supercell near O`Neill has finally accelerated northward and
weakened to the north of the surface warm front.  Stronger lingering
convection within the cluster has been aided by lift along the
leading edge of the eastward advancing cold pool, near where it
intersects the warm front.  However, it appears that this activity
will weaken further as it progresses eastward, with renewed
convective development possible in its wake, as the nose of a 30-40
kt southerly 850 mb jet remains focused near the O`Neill vicinity.
In the presence of modest shear, the newer convective development
may grow upscale and organize above the trailing convective outflow
overnight.  However, with updraft inflow likely to be characterized
by rather modest to weak instability, the risk for convection to
produce severe hail and wind seems likely to remain low.

..Kerr.. 06/21/2024

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

ATTN...WFO...FSD...OAX...LBF...

LAT...LON   43309900 43719740 43479615 42419614 42389724 42179877
            42539883 42939888 43309900