United States, National Weather Service,

Summary of tornadoes and damages -- Summary of meteorological conditions -- Facts, findings, recommendations, and best practices. Pre-season awareness activities ; Severe Weather Awareness Weeks ; Media outreach ; SKYWARN spotter training ; StormReady Program ; Emergency management ; School administrators ; Adopt-a-county ; Emergency management web briefing pages -- Situational awareness of WFOs -- Internal WFO operations and planning -- Key operational systems. Weather surveillance radar : 1988 Doppler (WSR-88D) ; AWIPS ; NWR -- WFO tornado products and services -- Products and services by SPC -- Decision support and external communication. Pre-warning services ; Webinars ; Web graphics ; Multimedia web briefings ; NWSChat ; Direct contacts and emails ; Standard warning products ; Interactive NWS (iNWS) -- Dissemination -- Social media -- Operations and responses of external partners. Emergency managers ; School officials ; Media -- Societal impacts and public response. Receiving warning information ; Message comprehension: Unclear communication of increased certainty and intensity, Varying siren policies, Language barriers, Multiple tornadoes ; Confirmation ; Personalization: Communicating geographic specificity, The false alarm effect, Altering behavior, Weather myths as a barrier to personalizing the threat ; Public response summary -- Post-event activities and support. WFO staff ; Southern Region Operations Center ; Mapping of tornado tracks ; Damage surveys ; Post-event agency coordination -- Success stories resulting from NWS products/services.

"On April 27, 2011, a series of devastating tornadoes struck the southeastern United States. This tornado event was one of the deadliest in the country since systematic tornado record keeping began in 1950. With 316 fatalities (31 in Mississippi, 234 in Alabama, 32 in Tennessee, 15 in Georgia, and 4 in Virginia), it ranks with the 1974 Super Tornado Outbreak and resulted in more deaths than the 1965 Palm Sunday Outbreak. In addition, there were more than 2,400 injuries. Damages from this outbreak totaled over $4.2 billion. The National Weather Service (NWS) formed a Service Assessment Team to evaluate its performance. To strengthen NWS relationships with other federal agencies involved with disaster work, for the first time this assessment had a co-leader from the Federal Emergency Management Agency. The team interviewed staff and reviewed products from the Storm Prediction Center (SPC), Weather Forecast Offices at Memphis and Morristown, TN, Jackson, MS, Huntsville and Birmingham, AL, and Peachtree City, GA. The team gathered feedback from partners and users of NWS products including media outlets, Emergency Managers at the state and local level, first responders, and the public. One of the team's tasks was to assess societal impacts of this event. This tornado outbreak was anticipated and forecast days in advance. The SPC began focusing on the affected area in its convective outlook products 5 days prior to the event. It continued emphasizing, refining, and enhancing the threat leading up to the event, ultimately issuing a high risk convective outlook on the morning of April 27 for a large portion of the impacted area. The Weather Forecast Offices (WFO) in the affected area prepared for severe weather operations and indicated the risk of severe weather and tornadoes as much as 5 days in advance. Hazardous Weather Outlooks, Web images, pre-recorded multimedia briefings, and webinars discussed the potential impacts. Emergency Managers and media staff interviewed indicated they were well prepared for the severe weather that occurred."--Page 1.

Professional Paper

Southern States

National Weather Service (NWS)