The NWS Storm Prediction Center has issued a
Severe Thunderstorm Watch for portions of
western Iowa
southwest Minnesota
northeast Nebraska
southeast South Dakota
Effective this Thursday night and Friday morning from 705 PM
until 200 am CDT.
Hail to 3 inches in diameter... thunderstorm wind gusts to 70
mph... and dangerous lightning are possible in these areas.
The Severe Thunderstorm Watch area is approximately along and 95
statute miles east and west of a line from 25 miles west
northwest of Worthington Minnesota to 15 miles south southwest of
Tekamah Nebraska. For a complete depiction of the watch see the
associated watch outline update (wous64 kwns wou8).
Remember... a Severe Thunderstorm Watch means conditions are
favorable for severe thunderstorms in and close to the watch
area. Persons in these areas should be on the lookout for
threatening weather conditions and listen for later statements
and possible warnings. Severe thunderstorms can and occasionally
do produce tornadoes.
Discussion... cu/tcu field and scattered thunderstorms are beginning
to increase over northeast neb/southeast SD... and will likely track
eastward into IA through the evening. Other storms may redevelop
through the evening over this same area as low level jet increases.
Strong instability and 50-60 knots of effective shear will promote
supercells capable of very large hail and damaging winds.
Aviation... a few severe thunderstorms with hail surface and aloft
to 3 inches. Extreme turbulence and surface wind gusts to 60
knots. A few cumulonimbi with maximum tops to 500. Mean storm
motion vector 27030.
... Hart