NORMAN, Okla. (AP) — Forecasters cautioned millions of people in Middle America to keep an eye to the sky Wednesday and Thursday amid threats of hail, high winds and strong tornadoes.
The Storm Prediction Center, in a midday update to its forecast Wednesday, upgraded to its second-highest advisory level — a moderate risk — while stressing that a significant tornado or two could form in a narrow stretch from northern Oklahoma to central Missouri.
Severe thunderstorms packing 70 mph winds and large hail made their way across central Missouri on Wednesday afternoon, including several capable of producing tornadoes.
Weather spotters reported a funnel cloud near Potosi in eastern Missouri at 3:35 p.m., while an hour earlier the Bates County emergency manager reported an EF0 tornado in southwest Missouri that destroyed a 60-foot machine shop.
Forecasters said more severe weather could form as far away as the plains of West Texas, urging people to have a plan in place should a tornado or other severe weather approach.
"Where to hide, emergency kits with medicines, snacks, water. Even something like sturdy shoes, gloves, long-sleeve shirts. If they get hit by a tornado they'll find they'll need those things pretty quickly," said meteorologist Erin Maxwell with the National Weather Service in Norman, Oklahoma.
"Know what you're doing and just don't panic," Maxwell added.
Indiana State Police said high winds toppled a tractor-trailer on Interstate 69 near Evansville, while utilities reported a number of power outages after wind gusts reached 70 mph.
Fewer than 1 million people were in Wednesday's "moderate risk" area between Wichita, Kansas, and Jefferson City, Missouri, but 34 million were under at least a slight risk of seeing damaging winds, large hail and possibly a tornado.
Emergency managers in Kansas and Illinois huddled separately to address the approaching storms. Kansas officials warned that hail could be the size of baseballs, while Illinois officials told residents they should be prepared to seek shelter if bad weather arrives.
Heat, humidity and the approach of a cold front and a jet stream could cause severe weather on Thursday, too. Forecasters said 57 million people were at an "enhanced risk" of seeing storms nearby, including residents in Chicago, Detroit and St. Louis, as well as those in Memphis, Tennessee, and Little Rock, Arkansas.
Areas that don't see strong storms Thursday could see heavy rain instead.
The Storm Prediction Center said Wednesday's storms in the southern Plains could be significant — defined as having 2-inch hail, 75 mph winds and tornado damage rated at EF2 or higher.
Emergency officials said a tornado touched down briefly Tuesday night in southeastern Kansas. Parts of Missouri and Indiana also had severe weather Tuesday.