Wednesday: Weather Technology and Science: Then and Now

The science and technology of meteorology has changed dramatically in the 40 years since the Candlestick Park tornado. The tornado occurred at a time when research on severe thunderstorms and tornadoes was really beginning to accelerate. Just two years before in 1964, the National Severe Storms Laboratory had been created and located in Norman, OK. In the years following this historic occurrence, NSSL would be responsible for dramatic progress in the understanding of severe thunderstorms and how tornadoes are produced. Unfortunately, though, in 1966 these new discoveries were still in the future.

The process of issuing tornado watches and warnings to the public was still at a developing state 40 years ago. The NWS was called the Weather Bureau in 1966, and was structured to have small offices in numerous communities nationwide versus the structure of today in which the NWS has larger warning and forecast offices in most major cities. In 1966, the Weather Bureau office in Jackson was located at Hawkins Field on the northwest side of the city of Jackson. The WB office in Jackson was equipped with a World War II era weather radar which was incredibly primitive in comparison to the WSR-88D Doppler radar used by the NWS today. The somewhat more modern WSR-57 weather radar was installed in Jackson in 1969, when the office was moved to the new Jackson International Airport at Thompson Field.

In order to try to detect tornadoes using the radar in use in 1966, weather radar observers would look into a viewing tube, like those used on military aircraft radar during the war, and attempt to discern “hook echoes” as indicators of possible tornadoes. It had been understood since the 1950s that “hook echoes” were correlated with the occurrence of tornadoes, but the reason why was not particularly well understood. In fact, renowned research meteorologist T. Theodore Fujita, later the inventor of the Fujita tornado damage scale, had just published a paper in 1965 theorizing the existence of the “supercell” thunderstorm. It would later be shown definitively that the supercell was a special type of rotating thunderstorm, associated with the hook shaped echo on radar, which produced the overwhelming majority of tornadoes. This discovery paved the way for the development of Doppler radar, which detected the movement of air and the rotation within a thunderstorm, enabling the advanced warning which is much more common today than even 15 years ago.

Communications have also obviously advanced tremendously over the last four decades. In 1966, the Weather Bureau relied on teletype and phone to get warnings and statements out to the public. The teletype circuits utilized a this time operated at only about 75 words per minute, and it would often take several minutes for a warning to actually be prepared and transmitted on the teletype. This is in stark comparison to the rapid communication of today, in which a warning message can be prepared by an NWS meteorologist in a matter of seconds, and once issued, is disseminated automatically and almost instantaneously via NOAA All-hazards Weather Radio (not deployed until 1975), the Internet, television, and other media. Additionally, other forms of warning the public such as outdoor sirens are much more common today than in the 1960s.

Obviously, advances in science and technology have enabled us to have a society that is much better prepared to protect people from the devastation of tornadoes. We at the NWS, with our partners in emergency management and the media, continue to strive to make people even safer from severe weather. However, we do have to be aware of the sobering reality that violent tornadoes like that of March 3, 1966, will still produce tremendous damage and casualties, no matter how much preparedness and advance warning are done.

Tomorrow we will look at other violent tornadoes in Mississippi history.

Thursday's Topic