Valid 110100Z – 111200Z
…THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS MUCH OF
NORTHERN NEBRASKA AND PARTS OF SOUTHEAST SOUTH DAKOTA…
…SUMMARY…
The threat for a couple tornadoes, damaging winds and hail will
persist mainly over northern Nebraska, southeast South Dakota, and
into northwest Iowa through evening.
…NE…SD…IA…MN…
Numerous storms persist this evening from the WY/NE border near a
dry line across northern NE and into southern SD along and north of
a warm front. Previously tornadic supercells have moved out of WY,
and may merge with the existing storms to the east eventually
forming an MCS. Damaging winds and hail will remain possible. A
tornado is still possible with any discrete cells across northern NE
as the low-level jet maintains large looping hodographs. The 00Z LBF
sounding shows 350 effective SRH along with substantial
instability, supportive of supercells. The very unstable air mass
extends eastward into western IA and may spread into far southern MN
later tonight, with damaging wind gusts possible. For more
information see mesoscale discussion 1951.
..Jewell.. 09/11/2019
$$