In this May 31, 2013 file photo, a tornado forms near Banner Road and Praire Circle in El Reno, Oklahoma. Forecasters are finding that the human mind is more difficult to predict than a stormy atmosphere. As the nation鈥檚 midsection braces for bad weather Tuesday, April 26, 2016, researchers are still trying to determine when to raise a general alarm with the public, so warnings will be more effective. The National Weather Service has even brought on a social scientist to help. AP
OKLAHOMA CITY, United States 鈥� School districts and authorities are bracing for the possibility for a severe weather outbreak that could produce powerful, long-track tornadoes and large hail on Tuesday in some central and southern Plains states.
The most dangerous weather 鈥� heavy winds, tornadoes and hail as large as baseballs or softballs鈥� will likely take aim at a 69,000-square-mile area stretching from southern Oklahoma to southern Nebraska, including the Oklahoma City area, according to the Storm Prediction Center in Norman.
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In all, 25 million people from the Rio Grande River in south Texas to Omaha, Nebraska, and the western regions of Missouri, Arkansas and Iowa are at a slight risk or higher of experiencing severe weather Tuesday. In the east, a separate storm system could bring thunderstorms, strong winds and hail to Philadelphia, Baltimore and Washington, D.C., but the risk of severe outbreaks is low.
鈥淲e shouldn鈥檛 assume that we鈥檙e going to have a lot of information 鈥� you know, a lot of lead time,鈥� Storm Prediction Center meteorologist Matt Mosier said. 鈥淲e may or we may not.鈥�
Administrators for Oklahoma City Public Schools, the state鈥檚 largest school district, planned to meet early Tuesday morning to assess the weather and determine whether to cancel classes, spokesman Mark Myers said in an emailed statement.
The University of Oklahoma has sent messages on social media since last week reminding followers to be aware of conditions, and will announce any potential decisions regarding class cancelations as early as possible, spokeswoman Catherine Bishop said.
The Storm Prediction Center issued a notice last week that severe weather was possible Tuesday in this part of the country and released updated forecasts in the days since. In recent years, authorities have been able to predict storm conditions like these several days in advance with greater confidence, Mosier said, though he noted that the weather doesn鈥檛 always pan out as expected.
鈥淚t鈥檚 never straightforward when you鈥檙e sitting here talking about (predicting) large tornadoes,鈥� Mosier said. 鈥淲e鈥檙e trying to be as confident or as accurate as we can.鈥�
Residents of impacted areas should develop a plan to take shelter from a quick-forming storm without driving in severe conditions, Mosier said.