May 3, 1999 Oklahoma/Kansas Tornado Outbreak

A total of 74 tornadoes touched down across the two states in less than 21 hours. At one point, there were as many as four tornadoes reported on the ground at the same time. The strongest tornado, rated a maximum F-5 on the Fujita Tornado Scale, tracked for nearly an hour and a half along a 38-mile path from Chickasha through south Oklahoma City and the suburbs of Bridge Creek, Newcastle, Moore, Midwest City and Del City.

As the skies cleared, the states counted 46 dead and 800 injured, more than 8000 homes damaged or destroyed, and total property damage of nearly $1.5 billion.

Despite these grim statistics, there were significantly fewer losses because of applied knowledge and new technologies developed through years of tornado research by NOAA scientists. The National Severe Storms Laboratory and other NOAA Research laboratories and joint institutes helped develop some of the primary tools used by the National Weather Service to forecast and nowcast the Oklahoma/ Kansas tornado outbreak. These tools include the NEXRAD Doppler radar, the Advanced Weather Interactive Processing System, the Warning Decision Support System and NOAA's Profiler Network.

NOAA's effort to modernize the National Weather Service paid off in this single event. Researchers estimate that more than 600 lives were saved as a result of timely and accurate warnings and the public's knowledge of tornado safety.

About the weather...

• The Great PlainsTornado Outbreak of May 3–4, 1999 (Norman NWS Forecast Office)
• Follow the progress, from initial outlook-for-the-day to status messages issued during field operations (VORTEX-99 field operations)
• Loop of visible and infrared GOES-8 satellite imagery (Scott Bachmeier)
• Special Issue of Weather and Forecasting dedicated to the 3-4 May 1999 Southern Plains Tornadic Outbreak (American Meteorological Society)

What others had to say....

• NOAA REPORT:
  June 1999 feature article by Keli Tarp
  Early Tornado Warnings Saved Lives on the Plains (.pdf, 415 kB)
• FEMA Mitigation Assessment Team report: Midwest tornadoes of May 3, 1999

More...

• May 3rd tornado outbreak poster (.pdf, 3 MB) [view low-res preview]

This F3 tornado (A3 on the outbreak map at right) was the first of a dozen tornadoes documented by scientists in the field on May 3. The same storm later produced an F5 tornado in Newcastle, Moore, and Del City, OK. The photo was taken from inside one of three VORTEX-99 mobile mesonet vehicles. Mobile mesonets - cars outfitted with mounted surface weather stations - are positioned near tornadoes to study the airflow around them. Research teams from VORTEX-99, a major field experiment designed to study tornado rotation, surrounded this tornado throughout its entire lifecycle, providing data that will either support or refute different ideas regarding tornado formation by NSSL scientists. Photo by Daphne Zaras/NSSL

Aerial view of tornado path in Newcastle/Moore/Oklahoma City on May 5, 1999: The dark mud trail shows the path of the tornado in the middle foreground and center of the picture. The tornado hit the intersection of I-44 (lower right) and the 16th Street (lower left) overpass in Newcastle. The Canadian River is in the upper third of the picture while the Moore and south Oklahoma City areas can be seen in the distance in the upper left of the photo. Photo by John Jarboe/NWS

Damage from the storms.

Damage from the storms.

Damage from the storms.

Damage from the storms.

Damage from the storms.

Damage from the storms.