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Storm spotting is a form of weather spotting in which observers watch for the approach of severe weather, monitor its development and progression, and actively relay their findings to local authorities. [1]
Storm spotting developed in the United States during the early 1940s. A joint project between the military and the weather bureau saw the deployment of trained military and aviation lightning spotters in areas where ammunitions for the war were manufactured. During 1942, a serious tornado struck a key operations center in Oklahoma and another tornado on May 15, 1943 destroyed parts of the Fort Riley military base located in Kansas. After these two events and a string of other tornado outbreaks, spotter networks became commonplace, and it is estimated that there were over 200 networks by 1945. [2] Their mandate had also changed to include reporting all types of active or severe weather; this included giving snow depth and other reports during the winter as well as fire reports in the summer, along with the more typical severe weather reports associated with thunderstorms. However, spotting was still mainly carried out by trained individuals in either the military, aviation, or law enforcement fields of service. It was not until 1947 that volunteer spotting, as it exists today, was born.
After a series of vicious tornado outbreaks hit the state of Texas in 1947, the state placed special emphasis on volunteer spotting, and the local weather offices began to offer basic training classes to the general public. [2] Spotting required the delivery of timely information so that warnings could be issued as quickly as possible, thus civilian landline phone calls and amateur radio operators provided the most efficient and fastest means of communication. While phone lines were reliable to a degree, a common problem was the loss of service when an approaching storm damaged phone lines in its path. This eventually led to amateur radio becoming the predominant means of communication and resulted in the installation of special amateur radio work zones within local weather offices. Volunteer spotters would come into the local office and run a radio net from within, directly relaying information to meteorologists.
The 1950s saw the deployment of the first dedicated weather radars in the United States, and by this time, civilian spotter networks were commonplace. The new reflectivity-only radars provided meteorologists with basic information and helped identify potentially severe storms, but due to the nature of weather radar, most precipitation was detected at a height of 1 kilometer or more above the ground. Ultimately, the radar cannot see what exactly occurs at the surface of the earth, and storm spotters now correlated ground truthing with radar signatures. This early conventional radar showed intensity of echoes, inferring precipitation intensity and types, and the horizontal and vertical distributions provided information about storm structures and processes. The hook echo was a major method used as an indicator for potential for tornadic activity during the first decades of weather radar. During the 1990s in the US, Doppler weather radar was deployed, providing velocity data on echoes flowing toward and away from the radar location, which enabled inferences about storm rotation, such as mesocyclones, and other dynamics, as well as data on downbursts (and wind shear aloft). The 2010s brought polarization radar in the US, which enabled confirmation of the presence of stronger tornadoes by discerning nonmeteorological echoes colocated with rotation in velocity data, which indicates the presence of lofted debris. However, radar is still limited by factors such as not capturing near surface environment and limitations on spatial and temporal resolution. Therefore, ground truth information remains important. [3]
New spotter technologies and training techniques have been developing since the 1960s. Prior to the 1960s, the vast majority of amateur radio communication relied on AM-modulated signals and the use of simplex. It was not uncommon for spotters to hear the distant net control station and not hear other mobile or base stations which were much closer. After 1960, amateurs adopted the use of FM repeaters which operated in the VHF spectrum. The use of FM repeaters was a huge advancement for storm spotters; spotters could now hear each other regularly. The low noise floor and greatly improved audio quality meant much better signal reception for all stations. By the 1970s, nearly all spotter radio activity consisted of half-duplex FM repeater use. [4] The next major technology to aid spotters was the development of the cell phone in the late 1970s and early 1980s. It was then possible for non-amateur radio operators to directly report severe weather.
Storm spotting became more popular with the public during the late 1980s and early 1990s. During this period, a number of NSSL (National Severe Storms Laboratory) projects were carried out, some of which were documented and broadcast on television in a number of specials. [5] Spotters and their actions were believed to have saved lives while also aiding university research groups, which dropped sensors such as TOTO in the path of tornadoes and at times fired rocketsondes directly at or very close to tornadoes. [6] At about the same time, early storm chasers were popularized and associated with spotters. It is believed this association is what has led many in the present era to associate storm chasers and storm spotters as carrying out the same actions or having the same goals.[ citation needed ]
Technological advances such as the Internet, weather radio, pagers, and cell phones have made spotter activation quick and efficient; however, the basic goal of spotting has remained relatively unchanged to this day. In making these reports, spotters use a specialized set of jargon and slang to describe their observations. [7]
The primary group responsible for storm spotting in the U.S. is known as Skywarn. Many individuals hold Skywarn certification and/or amateur radio licenses. Other spotters are part of organized and highly trained local spotter groups, reporting their observations to the local emergency management office or National Weather Service office responsible for that area. A Skywarn group is either directly or indirectly affiliated or associated with the local weather office, and in many cases other agencies responsible for the well-being of individuals. Today, amateur radio still plays a key role, as most spotters opt to attain their radio licenses; however, cell phones are an ever increasingly popular means to directly relay information, along with other on-line spotter reporting protocols such as The Spotter Network. [8]
Other spotters groups have formed in various countries. Canwarn is the Canadian spotter program run by Environment Canada and similarly the Australian Bureau of Meteorology runs the ASP (Australian Storm Spotters) program in Australia. In the United Kingdom, the TORRO has operated a network of observers since the 1970s. Since the 2000s, about a dozen European countries (including the UK) have operated autonomous storm-spotting organizations under the auspices of Skywarn Europe.
Countries in Asia such as Malaysia introduced a Community Service Oriented application called 'RakanMET' which allows volunteer public weather reports/spotting and two-way communication between the public and the Meteorology Department of Malaysia with the live weather report using Global Positioning System (GPS) from the reporter's smartphone. [9] Such service allows better information sharing especially during monsoon seasons as storms are a lot more frequent.
While there is no question that storm spotting has saved many lives and aided weather agencies greatly, there is concern that storm spotting may actually put individuals in danger. It is a common practice for many spotters to leave their vehicles or places of shelter to better observe, but this also places spotters in a situation where they can be harmed or killed by lightning. Most spotting groups do not recommend that individuals leave their vehicles or places of safety. [10]
A storm spotter is volunteer or a paid county or municipal employee who is spotting as a community service. Most spotters work as part of an organized network and are in communication with their community or organization, which is in turn in communication with the National Weather Service. The purpose of spotting is to alert community officials and the NWS and assist them in warning the public. Schools, hospitals, and other facilities are encouraged to have spotters to alert people in their care of impending severe weather.
Most trained storm spotters in the US are volunteer HAM radio operators that are organized by the National Weather Service and local emergency management groups. Sometimes, police, fire, security and other safety personnel can act as spotters.
By contrast, storm chasing involves following a developing thunderstorm to view or photograph severe weather phenomena. Chasing may be done for educational purposes or scientific research but is mostly done for personal fulfillment.
The main difference between the two is storm spotters 'warn,' while storm chasers 'track.'
A person can be a storm spotter, a storm chaser, or both.
The US National Weather Service developed an organized storm spotter training system starting in the 1970's. Meteorologist Alan Moller played a significant role in the development of the effort. He believed that storm spotters are a vital part of the Integrated Warning System since they provide "ground truth verification" for forecasters. Moller developed Tornadoes: A Spotter's Guide (1977) and latter co-produced the "StormWatch" storm spotter training video in 1995 with meteorologist Gary Woodall and Texas Severe Storms Association (TESSA) chairman Martin Lisius. In 2001, TESSA began offering the Super Storm Spotter Training Session at its National Storm Conference. The session was created by Woodall to offer training that extended beyond the Weather Service's "basic" and "advanced" training. Training focuses primarily on the various weather elements storm spotters witness in the field including properly identifying tornadoes, wall clouds and other storm features.
The National Weather Service organizes in-person training sessions for storm spotters throughout the US. These often take place at a public venue such as a school or government building. Presentations usually include slide presentations and video. These sessions are free and open to the public for anyone wanting to become a spotter.
Some county spotter groups have regular over-the-air meetings using a local HAM radio frequency. This usually takes place on the same radio frequency used by the spotters during a severe weather event. The frequency connects spotters in the field to a network controller who relays reports to a Weather Service forecaster. Sometimes, the forecaster asks for only reports that exceed a certain severe threshold such as hail reports of a specific size or larger. If a forecaster thinks the storm may have immediate tornado potential, they will ask the spotters to relay only tornado and funnel cloud reports, or reports of rapid, low-level cloud base rotation. The forecaster will consider the spotter reports along with radar, local conditions, and sometimes live video feeds, to determine if a warning should be released to the public. If a warning is released, it will be sent to various outlets including social media, TV and radio broadcasters, and local emergency managers. The goal is to deliver accurate warnings to the public as quickly as possible.
A tornado is a violently rotating column of air that is in contact with both the surface of the Earth and a cumulonimbus cloud or, in rare cases, the base of a cumulus cloud. It is often referred to as a twister, whirlwind or cyclone, although the word cyclone is used in meteorology to name a weather system with a low-pressure area in the center around which, from an observer looking down toward the surface of the Earth, winds blow counterclockwise in the Northern Hemisphere and clockwise in the Southern. Tornadoes come in many shapes and sizes, and they are often visible in the form of a condensation funnel originating from the base of a cumulonimbus cloud, with a cloud of rotating debris and dust beneath it. Most tornadoes have wind speeds less than 180 kilometers per hour, are about 80 meters across, and travel several kilometers before dissipating. The most extreme tornadoes can attain wind speeds of more than 480 kilometers per hour (300 mph), are more than 3 kilometers (2 mi) in diameter, and stay on the ground for more than 100 km (62 mi).
Skywarn is a program of the National Weather Service (NWS). Its mission is to collect reports of localized severe weather in the United States. These reports are used to aid forecasters in issuing and verifying severe weather watches and warnings and to improve the forecasting and warning processes and the tools used to collect meteorological data. Reports are also used by local emergency managers and public safety organizations.
A tornado warning is a public warning that is issued by weather forecasting agencies to an area in the direct path of a tornado or a thunderstorm that is capable of producing a tornado. Modern weather surveillance technology such as Doppler weather radar allow for early detection of rotation in a thunderstorm, and for subsequent warnings to be issued before a tornado actually develops. It is nevertheless still not uncommon that warnings are issued based on reported visual sighting of a tornado, funnel cloud, or wall cloud, typically from weather spotters or the public, but also law enforcement or local emergency management. In particular, a tornado can develop in a gap of radar coverage, of which there are several known in the United States.
A severe thunderstorm warning is a type of public warning for severe weather that is issued by weather forecasting agencies worldwide when one or more severe thunderstorms have been detected by Doppler weather radar, observed by weather spotters, or reported by an emergency management agency, law enforcement, or the general public. Unlike a watch, a warning is issued to areas in the direct path of active severe thunderstorms, that are expecting a direct impact typically within an hour. Severe thunderstorms can cause property damage and injury due to large hail, high winds, and flooding due to torrential rainfall. The exact criteria to issue a warning varies from country to country.
The National Weather Service (NWS) is an agency of the United States federal government that is tasked with providing weather forecasts, warnings of hazardous weather, and other weather-related products to organizations and the public for the purposes of protection, safety, and general information. It is a part of the National Oceanic and Atmospheric Administration (NOAA) branch of the Department of Commerce, and is headquartered in Silver Spring, Maryland, within the Washington metropolitan area. The agency was known as the United States Weather Bureau from 1890 until it adopted its current name in 1970.
In the United States and Canada, the Amateur Radio Emergency Service (ARES) is a corps of trained amateur radio operator volunteers organized to assist in public service and emergency communications. It is organized and sponsored by the American Radio Relay League and the Radio Amateurs of Canada.
Storm chasing is broadly defined as the deliberate pursuit of any severe weather phenomenon, regardless of motive, but most commonly for curiosity, adventure, scientific investigation, or for news or media coverage. A person who chases storms is known as a storm chaser or simply a chaser.
Weather spotting is observing weather for the purpose of reporting to a larger group or organization. Examples include National Weather Service (NWS) co-op observers and Skywarn storm spotters.
The Tornado and Storm Research Organisation (TORRO) was founded by Terence Meaden in 1974. Originally called the Tornado Research Organisation, it was expanded in 1982 following the inclusion of the Thunderstorm Census Organisation (TCO) after the death of its founder Morris Bower and his wife. The current Head of TORRO is Paul Knightley, a professional meteorologist.
StormReady is a community preparedness program in the United States that encourages government entities and commercial gathering sites to prepare for severe storms. The program, sponsored by the United States National Weather Service, issues recognition to communities and sites across the country that demonstrate severe weather readiness. The program is voluntary, and provides communities with clear-cut advice from a partnership with the local National Weather Service Office, state and local emergency managers, and the media. The program has been credited with saving the lives of more than 50 movie-goers in Van Wert County, Ohio in November 2002. As of June 1, 2011, there were 1,752 StormReady sites in 50 states.
A Local Storm Report (LSR) is transmitted by the National Weather Service (NWS) when it receives significant information from storm spotters, such as amateur radio operators, storm chasers, law enforcement officials, civil defense personnel, firefighters, EMTs or public citizens, about severe weather conditions in their warning responsibility area. Those reports are received by local National Weather Service offices (WFOs), and they can be used to issue Severe Thunderstorm Warnings, Tornado Warnings, and other weather warnings/bulletins, in addition to the LSR.
CANWARN, acronym for CANadian Weather Amateur Radio Network, is an organized severe weather spotting and reporting program organized and run by the Meteorological Services Division of Environment Canada. What CANWARN members do is called ground truthing, they confirm and add information to the remote sensing observations of satellites and radar as well as provide information not observable by these technologies.
Convective storm detection is the meteorological observation, and short-term prediction, of deep moist convection (DMC). DMC describes atmospheric conditions producing single or clusters of large vertical extension clouds ranging from cumulus congestus to cumulonimbus, the latter producing thunderstorms associated with lightning and thunder. Those two types of clouds can produce severe weather at the surface and aloft.
The Texas Severe Storms Association (TESSA) is a national non-profit organization founded in 1993 by storm chaser and TESSA chairman Martin Lisius. The organization’s mission is to bring together both professional meteorologists and weather enthusiasts in an attempt to better understand dangerous storms through the collection and diffusion of knowledge. Its scope is national but focuses on Texas.
Skywarn Europe is a network of volunteer storm spotters throughout Europe based on the U.S. Skywarn program.
National Weather Service Lincoln, Illinois also known as National Weather Service Central Illinois is a weather forecast office responsible for monitoring weather conditions for 35 counties in Central and Southeastern Illinois. The Central Illinois office initially consisted of two forecast offices in Peoria and Springfield until the current location in Lincoln became the sole local forecast office in 1995. Federal meteorology offices and stations in the region date back to the 19th century when the Army Signal Service began taking weather observations using weather equipment at the Springer Building in Springfield. Since that time the presence of the National Weather Service greatly increased with the installation of new weather radars, stations and forecast offices. The current office in Lincoln maintains a WSR-88D (NEXRAD) radar system, and Advanced Weather Interactive Processing System (AWIPS) that greatly improve forecasting in the region. Lincoln is in charge of weather forecasts, warnings and local statements as well as aviation weather.
The Spotter Network (SN) is a system that utilizes storm spotter and chaser reports of location and severe weather in a centralized framework for use by coordinators such as emergency managers, Skywarn and related spotter organizations, and the National Weather Service. It uses GPS to provide accurate and automated position data of storm spotters and chasers for coordination and reporting, which in turn provides ground truth to public servants engaged in the protection of life and property. The network is a combination of locally installed software for position and status reporting and web-based processing, mapping, and reporting.
The following is a glossary of tornado terms. It includes scientific as well as selected informal terminology.
Alan Roger Moller was an American meteorologist, storm chaser, nature and landscape photographer known for advancing spotter training and bridging operational meteorology with research.
National Weather Service - Pleasant Hill/Kansas City, Missouri is a Weather Forecast Office (WFO) of the National Weather Service, which is responsible for forecasts and the dissemination of weather warnings and advisories for 37 counties in northern and western Missouri and seven counties in extreme eastern Kansas, including the Kansas City and St. Joseph metropolitan areas. Though, as the Storm Prediction Center (SPC) in Norman, Oklahoma is responsible for issuing severe thunderstorm and tornado watches, the Pleasant Hill/Kansas City WFO only composes outline and status updates for SPC-issued watches affecting any portion of its designated County Warning Area.
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