Millions of Americans across the country are on alert for a severe weather outbreak as violent, long-track tornadoes with damaging winds of up to 80 mph and large hail are expected across the Midwest and South with the cross-country storm moving east.

Twelve fatalities were reported in Missouri – the most of any state struck by the storm – from scattered twisters, thunderstorms and large hail that ravaged dozens of communities. “Homes and businesses have been destroyed, entire communities are without power and the road to recovery will not be easy,” Gov. Mike Kehoe said in a statement.