http://www.srh.noaa.gov/graphicast.php?site=oun&gc=2 ;NWS Norman, OK

Severe storms are expected to form Tuesday afternoon and continue through the evening and into the night. The strongest storms may produce hail larger than baseballs, damaging winds, and tornadoes. There is still some uncertainty regarding how many storms will form initially, but higher confidence in storms becoming widespread east of Interstate-35. In any case, it will be very important to pay close attention to the weather on Tuesday.