NOAA News || NOAA Home Page


Tornado AnimationJune 24, 1999 — NOAA's National Weather Service has developed "A Century of Weather Services," a two-minute video montage that traces a few of the technological advances made this past century, which have improved the agency's ability to forecast weather, water and climatic events. Included in the video are "B-Roll" shots of historic and modern footage of severe weather situations, old newspaper headlines, forecast technology, including animation, and other video clips. The montage and this tip sheet can assist you when developing stories for the approaching millennium. (Media can order "A Century of Weather Services," by calling Video Transfer, 301-881-0270.) You must download a free copy of RealPlayer G2 in order to see the video.Get RealPlayer G2 for free

Weathering The Century's Storms—Aiming To Be The "No Surprise" Weather Service
The 21st Century will be long remembered for its record-breaking weather events. The Galveston, Texas, hurricane of 1900, which killed more than 8,000; the Great Flood of 1993 that soaked America's heartland; and the "Storm of the Century" in 1993, which paralyzed the eastern third of the nation, all have places in the annals of weather history. Throughout the ages, the phenomena of weather has not changed, but the science and technology used to forecast weather have.

During the past 100 years, the National Weather Service has taken meteorology from folklore to forecasting and, with the help of the broadcast media, which relay crucial weather information, helped narrow the gap between life and death with its use of breakthrough technology. With an eye toward the new millennium, and with the completion of an ambitious, 10-year modernization effort this month, the NWS is poised to meet new meteorological challenges that lie ahead in understanding weather, water and climate.

The past century has seen a climb in the NWS' average lead times for severe weather warnings, which have helped save lives and property. For example, the average lead time for tornado warnings in 1998 was 11 minutes, which is more than triple the three-minute average lead time 20 years earlier. For flash flood warnings, the average lead time in 1998 was 50.6 minutes, a huge jump from the 7.7 minute average in 1987. And today's three-to-four day forecast is as accurate as the two-day forecast was 15 years ago. The improvements largely can be credited to upgrades in weather satellites, the Doppler radar network and the implementation of the award-winning Advanced Weather Interactive Processing System (AWIPS), a hallmark of the NWS modernization. By 2005, the NWS plans a 15-minute average lead time for tornadoes and a 65-minute lead time for flash floods. (Contact: John Leslie, NWS Public Affairs, 301-713-0622;

Hurricanes—From Folklore To Forecasting
In the record books, it remains the deadliest hurricane ever to make landfall in the United States, but the 1900 Galveston, Texas storm, which killed more than 8,000, is a benchmark that highlights how far hurricane forecasting has evolved. Last year, the U.S. braved 14 tropical storms (10 developed into hurricanes) and suffered 28 total fatalities. At the time of the Galveston hurricane, forecasters relied on ship reports, tidal measurements, barometric readings and the color of the sky as warnings that a tropical storm was approaching. This year, in the first hurricane outlook ever released by NOAA at the start of the June-November season, the NWS predicts an above average season for tropical storms, hurricanes and intense hurricanes for 1999. An early warning of this magnitude heightens awareness within communities prone to land-falling storms.

Jerry Jarrell, director of NOAA's National Hurricane Center, points to the use of the Geostationary Orbital Environmental Satellites (GOES), advanced computer models, Doppler radar and the high-altitude Gulfstream-IV reconnaissance jet as major reasons for improved hurricane forecasting in recent years. Two years ago, the NWS added another forecasting tool called the Global Positioning System Dropwindsonde, a device released from a reconnaissance aircraft into the core of the hurricane, where it measures the wind, temperature and humidity.

"For the first time, we have an instrument that can survive the turbulence in the eye wall of a hurricane," Jarrell said. "This invention reminds us that the more we learn, the less we know."

The NHC's emphasis in the new millennium will be improving the accuracy of track forecasting and the destructive winds in a hurricane, especially as it crosses the coastline and moves inland. (B-Roll footage includes: satellite imagery and color animation of Hurricanes Mitch, Linda and Hugo; surging waters hitting a coastline. Contact: Frank Lepore, National Hurricane Center, 305-229-4404,

From Telegraph To The Internet—Getting The Word Out
When the telegraph became operational in America in 1845, early meteorological visionaries saw the possibility of "forecasting" storms by telegraphing ahead that one was approaching. By the the 1940s, the Weather Bureau had switched from telegraph to a teletype communications system, where it issued forecasts more quickly.

Today, National Weather Service employees use an array of advanced technology that help develop and issue weather forecasts and warningsfrom the high-speed supercomputer, which handles up to 16 billion calculations per second to help generate long-range forecasts; to the Communications Gateway, which issues and receives around 400,000 weather bulletins each day. The public can access up-to-the minute weather news from NOAA Weather Radio and the Emergency Managers Weather Information Network (EMWIN). The public can also access updated weather information from several of the NWS' 150 different Web sites. The average number of hits each day to the NWS' top three Web sites —;;—is 3.57 million. (B-Roll includes footage of meteorologists using NWR. Contact: John Leslie, NWS Public Affairs, 301-713-0622.)

NOAA Weather Radio—Don't Leave Home Without It
Another key life-saving, technological advancement spearheaded by the NWS during the past century is NOAA Weather Radio. This device, developed in the mid-1950s, gives Americans up-to-the minute weather warnings and information 24 hours-a-day and can be the difference between life and death. During the recent May 3, 1999, tornado outbreak in Oklahoma and Kansas, a supervisor at Norland Plastics in Haysville, Kan., saved more than 100 lives by responding to warnings broadcast on the plant's NWR. Shortly after instructing employees to move to the basement, a twister devastated the entire building. No one was hurt and Norland employees credit the warnings.

In the future, additional NWR transmitters will continue to expand the nationwide network coverage to more rural areas. The newest radios can be programmed for specific areas and can wake up sleeping residents as dangerous weather approaches. The NWR program also will use computers to broadcast warnings to the public even faster. (B-Roll includes: a forecaster updating NOAA Weather Radio; Barry Reichenbaugh, NWS Public Affairs, 301-713-0622,

Cooperative Weather Observer Network and Skywarn—Volunteers Making A Difference
One mainstay in weather observation, not linked to technology but as crucial to the NWS today as it was 100 years ago, is the Cooperative Weather Observer Program. The program, a network of more than 11,000 weather enthusiasts scattered across the country, provides crucial data to the NWS, and that data becomes part of U.S. weather history when it is archived at the National Climatic Data Center in Asheville, N.C. Cooperative observers measure precipitation, air and water temperatures, wind speed, barometric pressure and send the information to the NWS. In many cases, being a cooperative weather observer is a time-honored, family tradition, passed down through several generations.

Skywarn is a NWS program of trained volunteer severe weather spotters. Skywarn volunteers support their local community and government by providing the NWS with timely and accurate confirmation of severe weather events. Reports from the spotters inform communities how they should respond as when severe weather strikes.(Contact: John Leslie, NWS Public Affairs, 301- 713-0622;;

Weather Balloons—Still Taking The Pulse Of The Skies
In 1909, the Weather Bureau began sending up free-rising balloons to retrieve the temperature, humidity and air pressure. Today, the NWS still uses weather balloons and launches them twice a day from each of the 121 forecast offices. Each balloon carries an instrument called a radiosonde, which contains sensors that measure atmospheric pressure, temperature and humidity.

The battery-powered radiosonde, about the size of a milk carton, relays the information it gathers to a sensitive ground receiver at a tracking station near the launch site. The balloon's movement also is tracked remotely, giving meteorologists insight on wind speed and direction. (B-Roll includes: Historic still shots of man holding a weather kite, a man in front of a weather plane, modern shots of weather balloon launches. Contact: John Leslie, NWS Public Affairs, 301-713- 0622)

Keeping Tabs On The Climate
It's been called the "Event Of The Century," but the 1997-1998 El Niño, an abnormal warming of the ocean temperatures across the eastern tropical Pacific, which impacted weather around the world, was a proud milestone for the NWS' long-range weather and climate forecast abilities. Scientists at NOAA's National Centers for Environmental Prediction (NCEP) saw the recent El Niño coming as early as six months in advance, and began issuing its forecast. It was the best monitored and the first El Niño ever predicted. Ants Leetmaa, head of NOAA's Climate Prediction Center, said "the observations of the climate system, combined with sophisticated ocean-atmosphere prediction models, and the science community's increased understanding of the atmospheric response, led to [that] incredibly bold forecast."

NCEP forecasters continue to monitor the current La Niña episode, the climatic opposite of El Niño, which they expect to linger until the end of 1999. (Contact: Susan Harrison, NWS Public Affairs, 301-763-8000, ext. 7007;;

Breakthroughs In Weather Forecasting Technology
The rapid pace of technology used to forecast weather after the 1970s, helped revolutionize the way meteorologists forecast the weather. Technological upgrades in the Doppler radar network, improvements in weather satellites and the completion of the modernization of the NWS, helped the NWS increase its average lead-time warnings for severe weather.

The centerpiece of the modernization is the Advanced Weather Interactive Processing System, a high-speed computer system that allows forecasters to display and analyze satellite imagery, radar data, automated weather observations and computer-generated numerical forecasts, all in one workstation. This month, AWIPS was recognized by the Computerworld-Smithsonian Award Program for best technology in the area of energy, environment and agriculture.

Though the average lead time for tornadoes was 11 minutes in 1998, the NWS gave Oklahomans and Kansans a 30-minute lead time before the May 3, 1999, tornado outbreak. By 2005, the NWS hopes to give Americans an average warning lead time of 15 minutes for tornadoes and 65 minutes for flash floods. (Contact: John Leslie, NWS Public Affairs, 301-713-0622; B-Roll includes: footage of the old and new version of GOES satellites, animation loop of GOES depicting U.S. coverage, footage of storm activity on Doppler radar screens.)

NWS Partners In The Warning Process
The NWS has partnerships with the private industry that help the agency provide the critical weather information for which the nation depends. A major partner is the media, which quickly broadcast weather warnings that can be viewed or heard immediately. Also, private-sector companies help finance and build the NOAA Weather Radio transmitters that carry life-saving weather updates to communities across the nation.

On the mitigation side, the NWS works closely with the Federal Emergency Management Agency, the American Red Cross and insurance companies to find ways to better prepare communities in advance of severe weather. The Emergency Managers Weather Information Network system helps FEMA and local emergency managers respond faster to severe weather events by giving them the latest weather warnings in real-time. (Contact: Barry Reichenbaugh, NWS Public Affairs, 301-713-0622.)

Winter Storms—Forecasting The Storm of the Next Century
One of the deadliest winter storms this century was the "Knickerbocker" storm of Jan. 27-28, 1922, when Washington, D.C., received a total of 28 inches of snow within 32 hours. More than 100 people died when the roof of the Knickerbocker Theater collapsed under the weight of the heavy snow. However, the most memorable snow storm during the past 100 years was "The Storm of the Century" in March 1993, a mega system that produced record snowfall, low temperatures, floods and even tornadoes, impacted more than 100 million citizens in 22 states in the eastern U.S., causing $2 billion in damages.

Unlike the Knickerbocker storm, NWS meteorologists, using improved technology from weather satellites, sophisticated computer models, Doppler radar, and NOAA Weather Radio, helped lessen the death toll with advance warnings and continuous updates. In 1993, the NWS' ability to predict accurate snowfall amounts was 37 percent. In 1997, the accuracy improved to 45 percent. The NWS plans to reach a goal of 75 percent snowfall accuracy by 2005. (B-Roll includes: old footage of winter storm with man pushing old-make vehicle in snow, newspaper headline and article from "The Storm of the Century." Contact: Bob Chartuk, NWS Public Affairs, 516-244- 0166, or Susan Harrison, 301-763-8000, ext. 7007.)

Progress In Forecasting Tornadoes
Twenty-five years before last month's eruption of tornadoes in Oklahoma and Kansas, there was the Super Tornado Outbreak of April 3-4, 1974, when 148 tornadoes ripped through 13 states. Back then, forecasters did not know that a tornado was imminent until it touched down. In 1999, the difference is the high-speed Advance Weather Interactive Processing System, and the high-resolution Doppler radar that detects twisters before they meet the ground, which gave Oklahomans and Kansans an average of 30 minutes lead time to take cover.

By 2005, the NWS strives to give Americans a 15-minute average warning lead time for tornadoes, with continued use of AWIPS and other improvements in technology. NWS Director Jack Kelly cautions: "Warnings do no good, if they go unheeded. Citizens must be prepared to act once they get the message." (B-Roll footage includes footage of active tornadoes. Contact: Keli Tarp, NWS Public Affairs, 405-366-0451)

Watching The Waters
By the end of the 1940s, the Weather Bureau had only primitive observation instruments and a thin reporting network to keep up with the nation's rivers and flood potential. As meteorologists improved their understanding of hydrology, so did the instruments and technology they used. The Doppler radar, images from the GOES satellites and advanced hydrologic models helped forecasters save lives during the costliest flood of the century. In 1993, flood waters soaked Grand Forks, N.D., and parts of nine other states, causing nearly $20 billion in damages.

Floods kill an average of 130 people each year and cause more than $3.5 billion in damage. The NWS continues to prepare Americans with the release of its Flood Outlook. This outlook, issued each spring and factors the added impact of snowmelt, predicts the likely trouble spots around the nation where flooding may pose a danger. Into the next millennium, the NWS will use technologies such as, the Advance Hydrologic Prediction System, a high-tech computer system that allows meteorologists to prepare long-range river and flood forecasts. This system was just successfully demonstrated in Des Moines, Iowa. (B-Roll includes: rising flood waters, emergency personnel rescuing citizens and stacking sand bags. Contact: Pat Slattery, NWS Central Region Public Affairs, 816-426-7621, ext. 621,