Ten takeaways from the recently released National Weather Service Assessment of the Super Tuesday Tornado Outbreak that occurred on February 5-6, 2008. The outbreak produced 87 tornadoes.
1. The event was well forecast, with the Storm Prediction Center Day 4-8 Outlook highlighting the threat a full six days out. A high risk outlook was issued the morning of the 5th. Emergency managers in the nine affected states reported they were well prepared. But still, 57 people died.
2. Every single fatality occurred within the boundary of a tornado watch and tornado warning. Lead time for tornado warnings on fatalities was 17 minutes. Emergency managers did express concern that watches are too big and last too long.
3. Storm based warnings worked well, but there were some problems. Some broadcast graphic systems could not display the polygons and still highlighted entire counties. NOAA Weatheradio cannot be limited to the polygon areas. The team found that warnings were not issued well downstream in the case of fast moving storms. Some problems arose when tornadoes were crossing from one NWS office area of responsibility to another.
4. Offices used assistant warning forecasters in Memphis, Paducah and Louisville. The second person sitting next to the warning forecast was able to manage the text products and be an extra set of eyes on the radar.
5. Sixty three percent of the fatalities occurred in manufactured housing.
6. Fifty percent of the people interviewed said they downplayed the forecasts because it was too early in the season for tornadoes.
7. The team found that wording of some warnings was not urgent enough. It was recommended that statements like “this is an extremely dangerous and life threatening situation” should have been employed in high confidence warnings. Tornado emergency wording was used twice by Memphis and by Huntsville during the event, but there was no NWS guidelines on using this level of warning. That is being rectified now.
8. The NWS Little Rock was well prepared when they had to assume responsibility for Memphis when a tornado was bearing down on the Memphis office.
9. The IEM Chat program which links emergency managers and media partners directly with NWS forecasters was given high praise.
10. The Dixie Alley phenomenon was covered, stating that the area from Little Rock to Memphis to Tupelo to Birmingham is especially vulnerable to killer tornadoes. Some reasons include the fact that a large percentage of the population lives in manufactured housing. Many of the tornadoes in the South occur at night and in forested areas, reducing visibility. In addition, there is no focused tornado season in the South, so awareness tends to wane. Early season storms can catch people off guard.
Each significant weather event yields clues as to how to improve the social interaction part of the warning process.
