Chasing the storm
The National Severe Storms Laboratory in Norman, Oklahoma dispatches “storm chasers” to track, follow, and observe the behavior of storms in a predicted tornado outbreak. The chasers manage to document the complete development of a tornado in Union City, Oklahoma on film and on an experimental Doppler radar system; for the first time, large-scale cloud rotation at high altitude is observed on radar prior to the appearance of a funnel cloud, a key discovery in tornado prediction. This phenomenon, called the Tornadic Vortex Signature, is a precursor to virtually every radar-detected tornado.
Nimbus 5
NASA launches the Nimbus 5 satellite, designed to observe weather patterns from orbit and test new weather and climate detection technologies. Launched into a polar orbit from Vandenberg Air Force Base in California, Nimbus 5 includes newly-developed experiments to examine Earth in the microwave and infrared portions of the spectrum.
NOAA-2
NASA and the National Oceanic & Atmospheric Administration launch NOAA-2, a weather satellite intended to operate in a near-polar low Earth orbit. NOAA-2 is based on the already-flown ITOS satellite design, and will function in orbit through October 1974, with a break of only a few months due to a failed vertical temperature profile radiometer instrument. NOAA-2 will be shut down in January 1975.
Landsat 1
Originally named ERTS-1 (Earth Resource Technology Satellite), NASA’s Landsat satellite, based on the Nimbus weather satellites, is launched to begin constant observations of Earth’s land, air and oceans. Landsat 1’s tour of duty lasts just under six years, during which it discovers a previously unknown island – never before spotted from land or sea – off the northeastern Canadian coast. Landsat 1 remains in service through 1978.
Tornado Intercept Project
Students and seasoned weather researchers at the National Severe Storms Laboratory in Norman, Oklahoma embark on the Tornado Intercept Project (TIP), a concerted effort to gather film footage of developing or active tornadoes in an effort to study wind and debris patterns. Though believed by some to be of limited scientific value, TIP is the beginning of “storm chasing” and yields major breakthroughs in scientific understanding of the formation of tornadoes just one year later.
The Fujita Scale
Dr. Tetsuya Theodore Fujita, a pioneering researcher in the formation and development of severe weather, proposes a scale for judging the intensity of tornadoes by the damage left behind. His five-point scale covers minimal tornadoes (F1) through storms capable of inflicting incredible damage (F5), with damage surveyed after a storm to determine the physical effects and the estimated wind speed needed to cause those effects. The Fujita Scale is adopted almost worldwide, remaining in widespread use by severe weather researchers and government agencies until it is supplanted by the more refined Enhanced Fujita Scale in the 1990s.
The voice of the National Weather Service
The National Weather Service’s NOAA Weather Radio system finally finds its purpose with the introduction of a piercing “warning tone” preceding emergency weather announcements such as severe weather warnings. Manufacturers of weather radio receivers (an item which hit the market in 1970) use the five-second burst of 1050Hz warning tone to trigger attention-grabbing alert sounds and then activate the radio so the relevant information can be heard. NOAA Weather Radio broadcasts on 29 stations around the country, and the agency continues to bring new transmitters online throughout the year.
The dawn of Doppler radar
The National Severe Storms Laboratory‘s 10cm Doppler weather radar begins full-time experimental operation in Norman, Oklahoma, just in time for the region’s active severe weather season. A surplus Air Force radar left over from the Distant Early Warning radar network (also known as the DEW Line) is installed and housed in a facility that’s also made of military surplus parts. There is no real-time display at first: researchers and meteorologists store the Doppler radar’s observations on computer tape that has to be processed and printed months after the fact, and compared to archived records from the existing WSR-57 radar at Norman.
NOAA-1
NASA and the newly-rechristened National Oceanic & Atmospheric Administration (formerly ESSA) launch NOAA-1, a weather satellite intended to operate in a near-polar low Earth orbit. Equipped with four cameras, NOAA-1 will operate in orbit for nearly a year before it begins suffering equipment malfunctions. Overheating in the spacecraft’s attitude control system forces ground controllers to turn off some of its weather sensing equipment, and NOAA-1 will eventually be shut down in August 1971.
NOAA
The United States government reorganizes ESSA (the Environment Science Services Administration) into NOAA or the National Oceanic & Atmospheric Administration, an agency responsible for weather prediction and research and for functions involving oceanic conditions, coastal fisheries, and then-current investigations of a potential Alaskan oil pipeline.
Nimbus 4
NASA launches the Nimbus 4 satellite, designed to observe weather patterns from orbit and test new weather and climate detection technologies. Nimbus 4 is among the first satellites to test what will become known as global positioning system technology, capable of pinpointing ground-based targets with special equipment. The satellite begins to experience intermittent attitude control problems in 1971, but remains in at least partial service through 1980.
TIROS-M / ITOS
NASA and ESSA launch the ITOS satellite, also known as TIROS-M, a next-generation weather satellite intended to take over from the constellation of short-lived ESSA weather satellites. With a configuration that is, for the first time, significantly different from the TIROS/ESSA satellites, the TIROS-M design’s shakedown cruise is a short and bumpy one: after system failures force a shutdown of the satellite’s attitude control system, it is shut down in mid-1971.
Nimbus 3
NASA launches the Nimbus 3 satellite, designed to observe weather patterns from orbit and test new weather and climate detection technologies. Nimbus 3 is the first Earth-orbiting spacecraft to test the SNAP-19 radioisotope thermoelectric generator system; devices similar to the SNAP-19 will become the primary power source for later deep space and outer solar system interplanetary missions. Nimbus 3 loses attitude control in 1970, but is kept online for engineering information-gathering purposes until 1972.
ESSA-9
The recently-rechristened Environmental Sciences Service Administration launches, with the help of NASA, ESSA-9, the latest in a constellation of weather satellites. ESSA-9 is the last weather satellite to carry the ESSA designation, as the government reorganizes ESSA into a new agency, NOAA, the following year. ESSA-9 remains in service until 1972.
ESSA-8
The recently-rechristened Environmental Sciences Service Administration launches, with the help of NASA, ESSA-8, the latest in a constellation of weather satellites operated by the former U.S. Weather Bureau. ESSA-8 is the first satellite in the ESSA constellation to boast a significant operational life span, watching Earth’s cloud patterns until it is shut down in 1976.
ESSA-7
The recently-rechristened Environmental Sciences Service Administration launches, with the help of NASA, ESSA-7, the latest in a constellation of weather satellites operated by the former U.S. Weather Bureau. Like many of the other ESSA satellites, technical problems plague ESSA-7, and its camera system fails within a year. Engineering tests are carried out with ESSA-7 after it goes blind until the satellite is shut down early in 1970.
ESSA-6
The recently-rechristened Environmental Sciences Service Administration launches, with the help of NASA, ESSA-6, the latest in a constellation of weather satellites operated by the former U.S. Weather Bureau. ESSA-6 remains in service until late 1969.
ESSA-5
The recently-rechristened Environmental Sciences Service Administration launches, with the help of NASA, ESSA-5, the latest in a constellation of weather satellites operated by the former U.S. Weather Bureau. Though suffering from a few technical glitches and system failures, ESSA-5 remains in service until late 1968.
Weather Radio expands
The U.S. Weather Bureau announces plans to expand its Weather Radio service across the country, with forecasts now prepared and worded for public consumption (as opposed to the service’s original 1950s mission of providing weather information for airline pilots). Concentrated primarily in coastal areas and a handful of inland population centers, the Weather Radio network has yet to become the Bureau’s primary means of disseminating emergency weather information, a mission it won’t take on until the 1970s.
ESSA-4
The recently-rechristened Environmental Sciences Service Administration launches, with the help of NASA, ESSA-4, the latest in a constellation of weather satellites operated by the former U.S. Weather Bureau. One of ESSA-4’s cameras fails to activate, and the satellite remains in service for less than one year.
ESSA-3
The recently-rechristened Environmental Sciences Service Administration (previously the U.S. Weather Bureau) launches, with the help of NASA, weather satellite ESSA-3, the third in a constellation of Earth-observing weather satellites. The timing of the launch is fortunate, as ESSA-3 takes up its station in orbit mere days before the unexpected shutdown of ESSA-1’s camera system. ESSA-3’s own camera system begins to fail in less than a year, and it is deactivated near the end of 1968 due to continued system failures.
Nimbus 2
NASA launches the Nimbus 2 satellite, designed to observe weather patterns from orbit and test new weather and climate detection technologies. Nimbus 2’s only means of data storage fails within weeks, and that system’s only backup fails later in the year. Nimbus 2 is shut down in 1969 when the system it uses to maintain orientation to Earth’s horizon also fails.
ESSA-2 launched
The recently-rechristened Environmental Sciences Service Administration (previously the U.S. Weather Bureau) launches, with the help of NASA, weather satellite ESSA-2, intended to be the second in a constellation of spaceborne observers of Earth’s weather. Virtually identical to ESSA-1, ESSA-2 monitors Earth’s cloud cover for over four years; it is decommissioned in 1970, not because it stops working, but because a newer satellite utilizes the same telemetry frequency.
ESSA-1: Operational TIROS
The recently-rechristened Environmental Sciences Service Administration (previously the U.S. Weather Bureau) launches, with the help of NASA, the first “Operational TIROS” weather satellite, ESSA-1. Based on the architecture of the later TIROS satellites, this is intended to be the first fully-operational, long-life weather satellite, in the tradition of many of the long-lived TIROS weather satellites. But eight months into its operational lifetime, ESSA-1’s on board camera system fails, rendering it blind – it becomes useless as a weather satellite and is kept online for engineering experiments until spring 1967.
ESSA
As part of a reorganization of agencies within the U.S. government in 1965, the country’s Weather Bureau becomes part of ESSA, the Environmental Science Services Administration, and is placed under the Department of Commerce. All weather prediction and analysis is now under the jurisdiction of ESSA, including a growing fleet of weather satellites operated jointly by ESSA and NASA. The agency will be renamed the National Oceanic & Atmospheric Administration in 1970.
TIROS-10
NASA and the United States Weather Bureau launch the tenth and final experimental TIROS weather satellite, TIROS-10. Continuing to test technological upgrades for a fully-functional weather satellite fleet, TIROS-10 also provides additional coverage during hurricane seasons, and remains operational for exactly two years, at which point NASA begins a planned shutdown and phase-out of the experimental TIROS satellites in favor of the Nimbus and ESSA weather satellites.
Palm Sunday Tornado Outbreak
On the 45th anniversary of a similar severe weather event, a major outbreak of violent tornadoes strikes the northern midwest, causing 271 deaths and over a thousand injuries in Wisconsin, Illinois, Indiana, Iowa, Ohio, and Michigan; 137 of the deaths occur in Indiana alone. With weather radar still in its infant state, a radio station in Cedar Rapids spots the first storm on its own radar, while nearby National Weather Service offices do not have radar yet. The U.S. Weather Bureau’s confusing system of “tornado forecasts” and “tornado alerts” is changed to more clearly delineated “watches” and “warnings” after this event.
TIROS-9
NASA and the United States Weather Bureau launch the ninth experimental TIROS weather satellite, TIROS-9. Heavier than any of the other TIROS experimental satellites, and with cameras mounted on opposite sides of the satellite’s cylindrical body to keep the Earth in view at all times. The result, in February, is the first-ever snapshot of the entire world’s weather patterns within a single day. TIROS-9 also carries other upgrades being considered for an upcoming fleet of full-time operational weather satellites, and remains in service for three and a half years.
Nimbus-1
NASA and the United States Weather Bureau launch the first test article of the next-generation weather satellite, Nimbus-1. Using the more advanced camera technology (including infrared filters to watch cloud motion even on Earth’s night side) tested aboard TIROS-8, Nimbus-1 provides a vast improvement on satellite weather observations over the hardware on the TIROS experimental satellites. The first Nimbus satellite remains in service for only a month; later Nimbus satellites continue to be launched into service well into the late 1970s, and most of them remain operational into the 1980s.
The National Severe Storms Laboratory
To further research into the formation and evolution of severe weather in the midwestern United States, the U.S. Weather Bureau establishes the National Severe Storms Laboratory in Norman, Oklahoma. Operating in close cooperation with the University of Oklahoma’s meteorology department and the Severe Local Storms Warning Service in Kansas City, the NSSL focuses on improving prediction and detection of destructive weather, including tornadoes, quickly fixating upon the potential of Doppler radar.