MD 0775 CONCERNING TORNADO WATCH 215… FOR NORTHEAST NEBRASKA TO NORTHEAST KANSAS
Mesoscale Discussion 0775
NWS Storm Prediction Center Norman OK
0323 PM CDT Fri May 12 2023
Areas affected...Northeast Nebraska to northeast Kansas
Concerning...Tornado Watch 215...
Valid 122023Z - 122230Z
The severe weather threat for Tornado Watch 215 continues.
SUMMARY...The severe threat across WW 215 will continue for the next
several hours. The tornado threat will likely be maximized in the
near-term across northeast Nebraska, while the severe threat is
expected to increase across eastern Nebraska to northeast Kansas
over the next couple of hours as storms mature.
DISCUSSION...Over the past 1-2 hours, regional reflectivity/velocity
imagery has shown several organized splitting supercells developing
along and ahead of a northward migrating dryline. Splitting
supercells have been observed within the arcing band of convection,
with the right moving cells exhibiting strong mesocyclones capable
of producing tornadoes (with a few tornadoes already reported). This
is likely due to enhanced low-level SRH along a subtle confluence
axis noted in recent surface observations. The storms associated
with recent tornado reports appear to be residing along this
boundary as they move to the northwest. This will maintain the
tornado threat for the next hour or so. Beyond this time frame,
increasing storm interactions casts some uncertainty into the
longevity of any one cell.
Further the southeast across eastern NE into far northeast KS, cell
development is noted along the dryline where richer boundary-layer
moisture is supporting MLCAPE values in excess of 1500-3000 J/kg.
Additionally, VWP observations from KOAX, supported by recent 19 UTC
soundings from OAX and TOP, suggest low-level SRH is on the order of
100-150 m2/s2, which should support an increasing tornado threat
over the next couple of hours as cells mature, but prior to gradual
upscale growth this evening. An additional watch may be needed in
the near-term for parts of northeast KS to address this concern.
..Moore.. 05/12/2023
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...EAX...FSD...OAX...TOP...GID...LBF...
LAT...LON 41009818 41499940 41690014 41920067 42340072 42810024
42979928 42739761 42149664 41329612 40349557 39689548
39449625 39409667 40359731 41009818
