More than 2 dozen reported tornadoes in 3 states amid outbreak in the Plains

Tornado watches are in effect for parts of six states.

More than 2 dozen reported tornadoes in 3 states amid outbreak in the Plains

There have been more than two dozen reported tornadoes in three states amid a twister outbreak in the Plains on Friday.

Twenty million Americans, from Texas to Iowa, are on alert Friday for tornadoes, large hail and damaging winds, as severe weather is expected to impact the Heartland into the weekend.

The highest tornado threat exists from the Dallas region north to Des Moines, Iowa.

There have been at least 25 reported tornadoes in Nebraska, Texas and Kansas so far on Friday, with some damage reported in northeast Texas and central Nebraska.

Tornado watches are in effect for parts of six states -- Iowa, Nebraska, Kansas, Missouri, Oklahoma and Texas, including Dallas -- into Friday afternoon and evening.

The National Weather Service in Omaha issued a tornado emergency for parts of east-central Nebraska Friday afternoon after a confirmed "large and destructive" tornado was seen over Elkhorn, Nebraska.

Two particularly dangerous situation tornado warnings were also in effect in Nebraska near Omaha and near Norfolk.

Three people were injured after a reported tornado severely damaged a building in Lancaster County, Nebraska, authorities said. The incident was reported around 3 p.m. CT. Friday at Garner Industries, the Lancaster County Sheriff's Office said. Approximately 70 people were inside the building when the reported tornado struck, with three transported to area hospitals in non-life-threatening condition, the sheriff's office said.

On Saturday, some of these severe storms could stretch as far north as Chicago; Milwaukee; Green Bay, Wisconsin; and Traverse City, Michigan. These areas will mostly see damaging winds and some hail.

The severe thunderstorms could also produce very heavy rain causing flash flooding, with the highest flash flood threat in Oklahoma, including Oklahoma City and Tulsa, and extending into northern Texas and eastern Kansas. Up to half a foot of rain is possible locally in a short amount of time.

The highest tornado threat on Saturday is across the Plains from Texas to Iowa -- including Oklahoma City; Kansas City, Missouri; Wichita, Kansas; and Des Moines -- in the afternoon and evening.

The tornado threat will decrease but not dissipate on Sunday, with storms expected to redevelop from Texas to Missouri to Illinois in the afternoon and evening. Severe weather with damaging winds, hail and an isolated tornado are possible in cities including St. Louis and Little Rock.

The flash flood threat will also move into Arkansas, including Little Rock, on Sunday.

The current tornado threat comes after Thursday saw four reported landspouts and tornadoes in four states -- Kansas, Colorado, Wyoming and Utah, primarily in rural areas. Parts of Kansas also saw hail larger than a baseball and winds gusting up to 70 mph.

Meanwhile, classic spring whiplash is expected for the Midwest and the Northeast this weekend, as temperatures are forecast to flip from freezing to summer-like 80s.

Eleven states were on frost and freeze alerts Friday morning, from Michigan to Maryland, with many areas dipping to freezing or below.

A major warm-up is expected Saturday through Monday, with temperatures to skyrocket into the 80s from Chicago to New York City.

Chicago is forecast to reach 80 degrees on Saturday, while New York City could reach 80 on Monday. In Washington, D.C., temps could get close to 90.