NOAA/NWS 1982 Williamson County / Marion, IL F4 Tornado Web Site
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A look back at the Williamson County event in 1982 underscores the vast improvements that have taken place in the past few decades thanks to technology. Listed below are several comparisons of technology and communications in the warning process between 1982 and today.
(1.) Believe it or not, NOAA's National Weather Service Forecast Office in St. Louis, Missouri had warning responsibility for Williamson County back in 1982. In fact, they covered nearly 80 counties across Illinois and Missouri--all the way down to Cairo, Illinois and the Missouri bootheel! This alone obviously placed a strain on the staff during warning operations at the St. Louis office. Created in 1984, NOAA's National Weather Service Forecast Office in Paducah, Kentucky has since acquired warning responsibility for 58 counties across southeast Missouri, southern Illinois, western Kentucky, and southwest Indiana. Part of the modernization of NOAA's National Weather Service during the last decade, this shift in warning responsibility has helped to lessen the workload for the more established offices. For instance, St. Louis now covers 46 counties--a far cry from what they had 30 years ago!
(2.) Research and technology have resulted in improved radar equipment to provide warning forecasters with a clearer picture of potentially severe storms. Back in 1982, most offices relied on either the WSR-57 or WSR-74C radars. Today, a network of over 140 WSR-88D (Weather Surveillance Radar--1988 Doppler) radar sites are strategically positioned at NOAA National Weather Service Weather Forecast Offices and Department of Defense sites across the United States. For instance, the WSR-88D generates numerous products from base data and algorithms to assist in identifying the impending severity of thunderstorms. Besides providing a better picture of storm structure via reflectivity, the WSR-88D adds the dimension of the Doppler effect to give forecasters an idea of the motion of air parcels within a thunderstorm. This allows for the detection of strong mid-level rotation which often precedes tornado formation. Computer technology also allows for time lapse of radar data, which clues the forecaster into storm motion and trends. While the Williamson County tornado was over nearly 100 miles from the St. Louis WSR-57 radar back in 1982, the storm would have much better coverage today from the Paducah WSR-88D, which is only 40 miles away.
(3.) The timeliness and resolution of satellite imagery have also improved since 1982. Twenty-five years ago, satellite images were taken in 30-minute increments, but were often not available to forecasters until a half hour later. Today, new GOES (Geostationary Operational Environmental Satellite) technology provides higher-resolution imagery of thunderstorm activity. Forecast offices may request rapid scan operation to receive images in only 7-minute increments during significant weather events. These pictures are made available to field forecasters in a matter of only 5 to 10 minutes.
(4.) Advancements in communications technology within the past 30 years have made for quicker dissemination of severe weather warnings and information to those who utilize NOAA National Weather Service products. In the days of AFOS (Automation of Field Operations) and teletype, it was not uncommon for warnings to take 5 or 10 minutes to reach the intended recipients once the forecaster decided to issue. Today, computer systems such as AWIPS (Advanced Weather Interactive Processing System) combined with sophisticated warning software allow warning forecasters to compose most warnings and statements in a matter of 1 or 2 minutes. High-bandwidth broadband, telephone, and satellite communications make it possible for warnings to reach their intended recipients within mere seconds after dissemination from NOAA National Weather Service offices. Those we serve may choose from a wide variety of devices to receive our warnings, including NOAA Weather Radio, the internet, e-mail, and even mobile phones!
(5.) Another striking example of improved warning dissemination is the advancement in NOAA Weather Radio All-Hazards services within the past 30 years. Back in 1982, the counties now served by WFO Paducah had spotty NOAA Weather Radio coverage by only four transmitters. Today, eighteen transmitters provide warning and forecast information for at least part of the WFO Paducah service area. Today's transmitters are generally more reliable, and most have an automated monitoring system to alert electronics technicians to potential transmitter or phone line problems. The recent automation of the NOAA Weather Radio All-Hazards broadcast allows for simultaneous broadcast of multiple warnings over multiple transmitters. Furthermore, Specific Area Message Encoding, or SAME coding, associated with severe weather warnings and statements allows for greater selectivity in deciding which warnings activate your NOAA Weather Radio All-Hazards receiver alarm.
(6.) External to NOAA's National Weather Service, improved communications technology has better-equipped the emergency management and law enforcement communities in disseminating warnings and responding to disasters. Trained spotters now have a better idea of when and where to concentrate their efforts. In addition, enhanced computer graphical technologies allow for quicker dissemination of weather information by local media outlets and private weather companies in an easily understood format.
Most importantly for all of us, more opportunity exists to increase public awareness on the dangers of hazardous weather and associated safety precautions before the next storm strikes.