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 severe thunderstorm capable of producing one, and advises individuals in that area to take cover. Modern weather surveillance technology such as Doppler weather radar can detect rotation in a thunderstorm, allowing for early warning before a tornado develops. They are also commonly 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. When radar is unavailable or insufficient, such ground truth is crucial. In particular, a tornado can develop in a gap of radar coverage, of which there are several known in the United States.
A tornado watch is a statement issued by weather forecasting agencies to advise the public that atmospheric conditions in a given region may lead to the development of tornadoes within the region over a period of several hours. In addition to the potential for tornado development, thunderstorms that develop within the watch area may contain large hail, straight-line winds, intense rainfall and/or flooding that pose a similar damage risk as the attendant tornado threat.
A severe thunderstorm watch is a statement issued by weather forecasting agencies to advise the public that atmospheric conditions in a given region may lead to the development of severe thunderstorms within the region over a period of several hours. The criteria for issuing a watch varies by country, and may also include torrential rainfall and tornadoes. A watch may also be issued several hours ahead of the arrival of a mature and organized complex of storms, or more clustered or discrete storm activity.
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.
Hurricane Betsy was an intense, deadly and destructive tropical cyclone that brought widespread damage to areas of Florida and the central United States Gulf Coast in September 1965. The storm's erratic nature, coupled with its intensity and minimal preparation time contributed to making Betsy the first tropical cyclone in the Atlantic basin to accrue at least $1 billion in damage. While the storm primarily affected areas of southern Florida and Louisiana, lesser effects were felt in the Bahamas and as far inland in the United States as the Ohio River Valley. Betsy began as a tropical depression north of French Guiana on August 27, and strengthened as it moved in a general northwesterly direction. After executing a slight anticyclonic loop north of the Bahamas, Betsy proceeded to move through areas of south Florida on September 8, causing extensive crop damage. After emerging into the Gulf of Mexico, the cyclone strengthened and reached its peak intensity equivalent to that of a Category 4 hurricane on September 10 before making its final landfall near Grand Isle, Louisiana, shortly thereafter. Once inland, Betsy was slow to weaken, and persisted for two more days before degenerating into an extratropical storm; these remnants lasted until September 13.
Hurricane Donna, known in Puerto Rico as Hurricane San Lorenzo, was the strongest hurricane of the 1960 Atlantic hurricane season, and caused severe damage to the Lesser Antilles, the Greater Antilles, and the East Coast of the United States, especially Florida, in August–September. The fifth tropical cyclone, third hurricane, and first major hurricane of the season, Donna developed south of Cape Verde on August 29, spawned by a tropical wave to which 63 deaths from a plane crash in Senegal were attributed. The depression strengthened into Tropical Storm Donna by the following day. Donna moved west-northwestward at roughly 20 mph (32 km/h) and by September 1, it reached hurricane status. Over the next three days, Donna deepened significantly and reached maximum sustained winds of 130 mph (210 km/h) on September 4. Thereafter, it maintained intensity as it struck the Lesser Antilles later that day. On Sint Maarten, the storm left a quarter of the island's population homeless and killed seven people. An additional five deaths were reported in Anguilla, and there were seven other fatalities throughout the Virgin Islands. In Puerto Rico, severe flash flooding led to 107 fatalities, 85 of them in Humacao alone.
The Weather Prediction Center (WPC), located in College Park, Maryland, is one of nine service centers under the umbrella of the National Centers for Environmental Prediction (NCEP), a part of the National Weather Service (NWS), which in turn is part of the National Oceanic and Atmospheric Administration (NOAA) of the U.S. Government. Until March 5, 2013 the Weather Prediction Center was known as the Hydrometeorological Prediction Center (HPC). The Weather Prediction Center serves as a center for quantitative precipitation forecasting, medium range forecasting, and the interpretation of numerical weather prediction computer models.
This article describes severe weather terminology used by the National Weather Service (NWS) in the United States. The NWS is a government agency operating as an arm of the National Oceanic and Atmospheric Administration (NOAA) branch. It defines precise meanings for nearly all of its weather terms.
Hurricane Wilma was the most intense tropical cyclone in the Atlantic basin and the second-most intense tropical cyclone in the Western Hemisphere, both based on barometric pressure, after Hurricane Patricia in 2015. Wilma's rapid intensification led to a 24-hour pressure drop of 97 mbar, setting a new basin record. At its peak, Hurricane Wilma's eye contracted to a record minimum diameter of 2.3 mi (3.7 km). In the record-breaking 2005 Atlantic hurricane season, Wilma was the twenty-second storm, thirteenth hurricane, sixth major hurricane, fourth Category 5 hurricane, and the second costliest.
A flash flood warning is a severe weather warning product of the National Weather Service that is issued by national weather forecasting agencies throughout the world to alert the public that a flash flood is imminent or occurring in the warned area. A flash flood is a sudden, violent flood after a heavy rain, or occasionally after a dam break. Rainfall intensity and duration, topography, soil conditions, and ground cover contribute to flash flooding.
The National Weather Service bulletin for the New Orleans region of 10:11 a.m., August 28, 2005, was a particularly dire warning issued by the local Weather Forecast Office in Slidell, Louisiana, warning of the devastation that Hurricane Katrina could wreak upon the Gulf Coast of the United States, and the torrent of pain, misery and suffering that would follow once the storm left the area.
In weather forecasting in the United States, "particularly dangerous situation" (PDS) is enhanced wording used by the National Weather Service to convey special urgency in some watch or warning messages for unusually extreme and life-threatening severe weather events, above and beyond the average severity for the type of event. It is used in the format "This is a particularly dangerous situation..." at the discretion of the issuing forecaster. A watch or warning bearing the phrase is referred to as a PDS watch or PDS warning as shorthand jargon.
The effects of Hurricane Wilma in Florida resulted in the storm becoming one of the costliest tropical cyclones in Florida history. Wilma developed in the Caribbean Sea just southwest of Jamaica on October 15 from a large area of disturbed weather. After reaching tropical storm intensity on October 17 and then hurricane status on October 18, the system underwent explosive intensification, peaking as the strongest tropical cyclone ever recorded in the Atlantic basin. Wilma then slowly weakened while trekking to the northwest and fell to Category 4 intensity by the time it struck the Yucatán Peninsula on October 22. Thereafter, a strong cold front swept the storm northeastward into Florida on October 24, with landfall occurring near Cape Romano as a Category 3 hurricane with winds of 120 mph (190 km/h). Wilma continued rapidly northeastward into the Atlantic Ocean and became extratropical on October 26.
A tornado emergency is an enhanced version of a tornado warning, which is used by the National Weather Service (NWS) in the United States during imminent, significant tornado occurrences in highly populated areas. Although it is not a new warning type from the NWS, issued instead within a severe weather statement or in the initial tornado warning, a tornado emergency generally means that significant, widespread damage is expected to occur and a high likelihood of numerous fatalities is expected with a large, strong to violent tornado.
A significant weather advisory was a hazardous weather statement issued by certain Weather Forecast Offices (WFO) of the National Weather Service (NWS) in the United States to alert the public of thunderstorm activity that is below designated severe criteria for and/or is not expected to produce severe weather. The title assigned to the advisory — alternately titled "significant weather alert" or referenced by its originating product, "special weather statement" — varied by the issuing WFO.
An extreme wind warning is an alert issued by the National Weather Service for areas that will experience sustained surface winds 100 knots or greater within one hour, due to a landfalling tropical cyclone. Extreme wind warnings are intended to provide guidance to the general public at a county or sub-county level when such winds pose a significant threat of casualties. Their issuance is intended to cover as precise of an area as possible and can be issued no earlier than two hours before the onset of extreme winds. The extreme wind warning should not be confused with tornado warnings, which covers rotating supercells from severe storms, and high wind warnings, which is similar, but used for non-severe/tornadic winds of 40 mph to 114 mph, mainly on land.
National Weather Service - Norman, Oklahoma is a Weather Forecast Office (WFO) of the National Weather Service based in Norman, Oklahoma, which is responsible for forecasts and the dissemination of weather warnings and advisories for central and most of western Oklahoma, and western portions of north Texas. It is located in the National Weather Center on the University of Oklahoma campus, where it acts as one of the NOAA Weather Partners, a group of close-together weather-related agencies of the National Oceanic and Atmospheric Administration. NWS Norman is currently overseen by Mark Fox, who serves as the Meteorologist In Charge of the office.
As Hurricane Isaias moved up the East Coast of the United States, a damaging outbreak of 39 tornadoes impacted areas from South Carolina to Connecticut between August 3–4, 2020. The most significant tornado of the outbreak was a large and intense EF3 tornado that obliterated a mobile home park near Windsor, North Carolina, killing two and injuring 14. This was the strongest tornado in the United States to be spawned by a tropical cyclone since 2005. In the end, the outbreak killed two and injured 26.
Hurricane Laura was a deadly and destructive Category 4 hurricane that is tied with the 1856 Last Island hurricane and 2021's Hurricane Ida as the strongest hurricane on record to make landfall in the U.S. state of Louisiana, as measured by maximum sustained winds. The twelfth named storm, fourth hurricane, and first major hurricane of the record-breaking 2020 Atlantic hurricane season, Laura originated from a large tropical wave that moved off the West African coast on August 16 and became a tropical depression on August 20. Laura intensified into a tropical storm a day later, becoming the earliest twelfth named storm on record in the North Atlantic basin, forming eight days earlier than 1995's Hurricane Luis.
