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Fast Facts

  • According to the latest information from the Oklahoma Department of Emergency Management, 3 people were killed and over 450 people were injured in the state during the tornado outbreak. More information can be found on the OEM Situation Update web page.

  • 56 tornadoes were documented in the state of Oklahoma, 36 of which were in the NWS Norman area of responsibility.

  • There were 2 EF4 tornadoes (the Moore-Lake Draper-Harrah and Norman-Little Axe-Pink tornadoes), and 4 EF3 tornadoes.

  • From 5:00 PM to 7:41 pm CDT, there was at least one tornado occurring in Oklahoma every minute. A total of 42 different tornadoes occurred within this time.

  • Between 5:33 PM and 5:59 PM CDT, there were between three and five tornadoes occurring simultaneously every minute. This includes a portion of the life cycle of 13 different tornadoes, including both EF4 tornadoes and two EF3 tornadoes.

  • A total of 31 Tornado Warnings (TOR), 19 Severe Thunderstorm Warnings (SVR), 95 Severe Weather Statements (SVS), 3 Warning Decision Updates (AWU), 12 Regional Weather Discussions (NOW) and 8 Significant Weather Advisories (SPS) were issued during the tornado outbreak. In addition, 22 Hazardous Weather Outlooks (HWO) mentioning the impending event were issued on May 4-10, 2010. A total of 8 multimedia weather briefings discussing the event were issued by NWS Norman on May 9-10, 2010.

  • The NWS Norman staff began to mention the possibility of a significant severe weather event on May 4, 2010. The Hazardous Weather Outlook used the included the sentence: "THERE ARE SOME INDICATIONS OF A POTENTIALLY SIGNIFICANT INCREASE IN THE RISK OF SEVERE WEATHER NEXT MONDAY." A Graphicast issued at 530 am CDT on May 4, 2010 also highlighted the potential for severe weather. Graphicast for 530 am CDT on May 4, 2010

  • The tornado damage paths are spread over a north-south area of over 200 miles from near the Kansas-Oklahoma border to near the Red River.

  • Very large hail was reported in several locations, up to the size of softballs (4.5").

Information Sources