A weather cancellation or delay is closure, cancellation, or delay of an institution, operation, or event as a result of inclement weather. Certain institutions, such as schools, are likely to close when bad weather, such as snow, flooding, air pollution, tropical cyclones, or extreme heat, causes power outages, or otherwise impedes public safety or makes opening the facility impossible or more difficult. Depending upon the local climate, the chances of a school or school system closing may vary. While some regions may close or delay schools when there is any question of safety, others located in areas where bad weather is a regular occurrence may remain open, as local people may be accustomed to travelling under such conditions.
Many countries and sub-national jurisdictions have mandates for a minimum number of school days in a year. To meet these requirements, many schools that face a likelihood of closure build a few extra school days into their calendar. If, by the end of the year, these days are unused, some schools give students days off. If all snow days are exhausted, and inclement weather requires more closures, schools usually make the days up later in the year. US State education departments have, for example by administrative decision late in the 2015 Texas school year, occasionally issued waivers to schools, so that they do not need make up days for weather-related cancellations. [1] [2]
Safety is the central factor in deciding whether to cancel or delay. Officials may close schools to prevent accidents and other problems caused by inclement weather.
Minor storms, when safety is of less concern, may cause few or no cancellations or delays. In severe inclement weather, however, only the most essential operations remain functional. Operations considered essential include health care, emergency services, and retail of basic necessities. In health care environments, employees may remain at the facility around the clock if travel is impaired or dangerous, as those facilities contain basic accommodations for sleeping and eating such as on-call rooms. While tourist attractions generally close, those housing live animals may need essential employees to provide proper animal care.
Television and radio services generally keep operating (unless they in turn are taken off the air by the weather), and travel as necessary. Elected officials travel as necessary to provide services to the public. Snow removal crews remain at work.
Some inclement weather makes road passage impossible or difficult. In developed nations, municipalities attempt to clear snow-covered roads—but this is not always possible, and often many cannot travel. In deeper snowfalls, personal vehicles may become trapped, and their removal may take several days. This influences decisions on closures beyond the end of snowfall. The ability of employees to reach work places is a factor.
Various types of severe weather can damage structures temporarily or render them permanently useless, cause power outages, or prevent heat or air conditioning from working.
A snow day in the United States and Canada is a day that school classes are cancelled or delayed by snow, heavy ice, or extremely low temperatures. Similar measures occur in response to flooding, tornado watches, and severe weather (storms, hurricanes, dense fog, heavy snow, etc.). The criterion for a snow day is primarily the inability of school buses to operate safely on their routes and danger to children who walk to school. Often, the school remains officially open even though buses do not run and classes are cancelled.
More and more schools are closing due to extreme heat, "heat days". Heat days are like snow days. Some districts (San Diego Unified) provide schools with an operational procedure that is used as a guideline to address what actions schools should take at different levels of rising temperatures. [3]
Schools and businesses may also be cancelled for reasons other than bad weather such as a pandemic, power failure, terrorist attack, or bomb threat, or in honour of a school staff member who has recently died. In some cases, only one school or business in a town may close, due to localized issues such as a water main break or a lack of heat or air conditioning.
In northern areas of the United States, where municipalities are well equipped to handle heavy snowfall, snow days occur when extreme winter weather events overwhelm typical efforts to safely clear main roads of snow and ice (1 to 2 feet of snow). Weather induced cancellations or delays can also happen in more temperate southern regions, which are traditionally less prepared to handle such situations. In areas less accustomed to snow—such as Atlanta, Dallas, Memphis, or Chattanooga—even small snowfalls of an inch or two may render roads unsafe, while in some large northern metropolitan areas, effectively mobilized plow and road salt crews can clear 10 or more inches of overnight snow and ice accumulation before the morning commute.
In most areas, schools include extra days in their calendar as "built-in" snow days which allow a school to get in the minimum number of hours or days for instruction. [4] When the number of snow days taken is less than the number of built-in days, the days are given back by extending Memorial Day weekend, or making the school year end earlier. Once the number of snow days taken exceeds the number of built-in days, the snow days must be made up. [5] [6] [7] In other states, like New Jersey, all snow days must be made up. [8] For example, schools may open school on some federal holidays, shorten spring break, or sometimes make the school year end later. However, some schools are more forgiving, and do not mandate make-up days. In the event of heavy snow, tools have arisen to help students calculate the chance of a weather-related cancellation, most commonly snow days.
In the United Kingdom, snow days are a relatively uncommon event, especially in southern regions. Scottish, Northern Irish, Welsh, and Northern English schools may experience some closures during the winter months, often due to travel disruption. In Southern England, however, significant snowfall is a less frequent event, rarely lasting for more than a few days across low-lying areas.
Very few schools in Australia regularly receive any, let alone significant snowfalls. Those who do, will generally have their own local snow policies, similar to how schools in bush fire or flood-prone areas will have policies to handle these events. If a school is closed due to snow, it is treated as an emergency closure and no additional days are added to make up for the closure.
Instead of cancelling an entire school day, some schools may delay opening by, for example, one or two hours, or announce a particular opening time. This can be advantageous in places where schools are not charged a "snow day" by delaying their opening. Many school authorities cancel the whole morning kindergarten under these circumstances. This is particularly common during snowfalls of 2 inches (5.1 cm) or less in areas not accustomed to winter snowfall, such as the Baltimore metropolitan area and points south.
In the event of fog, some schools may delay the opening of school three hours but extend the day an extra hour.
Contrary to popular legend circulated among school children, schools rarely close due to hot weather and if they were it would be a decision based on a risk assessment by school staff. There is no set policy stating at what point schools close, and most states explicitly state that schools do not close simply due to hot weather. Schools may however modify their operations to ensure student and teacher welfare, for example by cancelling sport activities or relocating to a part of the school with access to air conditioning. [9]
Non Government Schools may follow their own procedures however.
As per Department of Education (DepEd) Order No. 37 series of 2022, Classes and work in schools are cancelled or suspended classes during a typhoon, heavy rainfall, flood, earthquake, and power outages/power interruptions/brownouts.
During a typhoon, DepEd said that in-person, online classes and work from Kindergarten to Grades 12 and Alternative Learning System (ALS) in all levels are “automatically cancelled” in public schools situated in Local Government Units (LGUs) issued with Tropical Cyclone Wind Signals (TCWS) 1, 2, 3,4, or 5 by the Philippine Atmospheric, Geophysical, and Astronomical Services Administration (PAGASA). Also, in-person, online classes and work at all levels are also automatically cancelled in schools situated in LGUs issued with Orange and Red Rainfall Warning by the PAGASA as well as areas issued with a Flood Warning by PAGASA. While private schools must abide the existing rules of Executive Order No. 66 of the Department of Education (DepEd), classes in private schools and work in government institutions could be suspended automatically depending on the typhoon warning signal raised by the PAGASA in a particular area, such as when Tropical Cyclone Wind Signal (TCWS) No. 1 was in effect, preschool and kindergarten classes in the affected areas shall be automatically cancelled or suspended, when Tropical Cyclone Wind Signal (TCWS) No. 2 was in effect, preschool, kindergarten, elementary and secondary classes in the affected areas shall be automatically cancelled or suspended and when Tropical Cyclone Wind Signal (TCWS) No. 3 or above was in effect, classes in all educational levels (including colleges and universities) in the affected areas shall be automatically cancelled or suspended. In an absence of a typhoon signal warning and during floods, the executive of a local government units (LGUs) in their own capacity as chairpersons of the local disaster risk and management councils throughout the Philippines could declare a suspension of classes and government office work depending on the situation in their area of responsibility. [10] [11]
Workplaces are less likely to close during mildly inclement weather, but the more severe the storm, the more likely a workplace is to close.
Some employers who use the most essential types of employees, such as health care facilities, have some or all of their employees stay and sleep on the premises while off duty if bad weather that hampers commuting is anticipated. Many supermarkets, convenience stores, and gas stations try to remain open to meet public need and the opportunity for increased business. Less critical businesses, such as clothing or antique shops, may close in moderate or severe weather.
In most severe storms, police and fire departments use specialized vehicles to respond to emergencies. Other workers involved in handling issues pertaining to the inclement weather, such as snow plow operators, report to work, and reporters and local elected officials stay on duty to serve the public.
In severe weather, airlines, rail service providers, bus operators, and other public transport may cancel or reduce services. Route impassability, airport closure, employees' safety, and public safety may result in such action. However, some modes of transport are more prone to severe weather than others, and different forms of bad weather have different impacts.
In air travel, the decision is often based on the guidelines of the country's civil aviation authority, such as the Federal Aviation Administration (FAA) in the United States.
Even when the service does operate, unplanned delays are possible, as operators take extra precautions or routes are congested. The level of service provided may be diminished due to a lower demand for service, fewer operators being available, or fewer passable routes. Yet sometimes demand for public transport may increase as more commuters choose not to drive their own vehicles.
In particularly hot weather, rail vehicles may be delayed by the expansion of the steel tracks.
Public transport may continue to operate on main arteries, though they may still experience delays. Buses that operate on secondary roads, especially those that are narrow or difficult to negotiate, may either be completely cancelled or diverted to a main road.
Although bad weather generally has little effect on an underground subway system in a major metropolitan area, electricity outages and flooding may disrupt services. For example, on August 8, 2007, following a tornado in Brooklyn in New York City, the New York City Subway flooded, causing all trains to grind to a halt during rush hour. [12] Increased demand may result from employers and schools clearing out in anticipation of a tropical cyclone, hurricane, or other severe weather system as people turn to the subway when other modes of transport are threatened. In some cases, including Hurricane Sandy in 2012, transit services may be totally suspended for the storm's duration.
Severe Tropical Storm Halong, known in the Philippines as Typhoon Cosme, was the fourth severe tropical storm named by the Japan Meteorological Agency (JMA), which is the Regional Specialized Meteorological Centre for the Northwestern Pacific Ocean. The Joint Typhoon Warning Center also recognized Halong as the fifth tropical depression, the fourth tropical storm, as well as the third typhoon of the 2008 Pacific typhoon season.
The February 2009 Great Britain and Ireland snowfall was a prolonged period of snowfall that began on 1 February 2009. Some areas experienced their largest snowfall levels in 18 years. Snow fell over much of Western Europe. The United Kingdom's Met Office and Ireland's Met Éireann issued severe weather warnings in anticipation of the snowfall. More than 30 centimetres (12 in) of snow fell on parts of the North Downs and over 20 cm (8 in) in parts of the London area. Such snow accumulation is uncommon in London. On the morning of 6 February the majority of Great Britain and Ireland had snow cover, with the area surrounding the Bristol Channel being most affected – 55 cm (22 in) had settled overnight around Okehampton, Devon, South West England with similar depths in South Wales. In Ireland the highest totals were recorded around East Kildare and County Wicklow where up to 28 cm (11 in) fell around Naas, County Kildare and even more along the Wicklow Mountains. The last time such widespread snowfall affected Britain was in February 1991. On the 2nd a total of 32 cm (13 in) had fallen in Leatherhead, Surrey just south of the M25. Also 30 cm (12 in) had fallen over the South Downs and 26 cm (10 in) in higher areas of Brighton.
A weather warning generally refers to an alert issued by a meteorological agency to warn citizens of approaching dangerous weather. A weather watch, on the other hand, typically refers to an alert issued to indicate that conditions are favorable for the development of dangerous weather patterns, although the dangerous weather conditions themselves are not currently present.
The February 25–27, 2010 North American blizzard was a winter storm and severe weather event that occurred in the Mid-Atlantic and New England regions of the United States between February 24 and 26, 2010. The storm dropped its heaviest snow of 12 to 24 inches across a wide area of interior New England, New York, and Pennsylvania. The storm also brought flooding rains to coastal sections of New England, with some areas experiencing as much as 4 inches (10 cm). Aside from precipitation, the Nor'easter brought hurricane-force sustained winds to coastal New England.
Global weather activity of 2009 profiles the major worldwide storms, including blizzards, tornadoes, ice storms, tropical cyclones and other meteorogical events, from January 1, 2009, to December 31, 2009. Wintery storms are events in which the dominant varieties of precipitation are forms that only occur at cold temperatures, such as snow or sleet, or a rainstorm where ground temperatures are cold enough to allow ice to form. It may be marked by strong wind, thunder and lightning, heavy precipitation, such as ice, or wind transporting some substance through the atmosphere. Summer storms including flooding, severe thunderstorms and extratropical cyclones are also included in this list to a certain extent.
Global weather activity of 2006 profiles the major worldwide weather events, including blizzards, ice storms, tropical cyclones, tornadoes, and other weather events, from January 1, 2006, to December 31, 2006. Winter storms are events in which the dominant varieties of precipitation are forms that only occur at cold temperatures, such as snow or sleet, or a rainstorm where ground temperatures are cold enough to allow ice to form. It may be marked by strong wind, thunder and lightning, heavy precipitation, such as ice, or wind transporting some substance through the atmosphere. Other major non winter events such as large dust storms, Hurricanes, cyclones, tornados, gales, flooding and rainstorms are also caused by such phenomena to a lesser or greater existent.
The 2011 Groundhog Day blizzard was a powerful and historic winter storm that affected large swaths of the United States and Canada from January 31 to February 2, 2011, especially on Groundhog Day. During the initial stages of the storm, some meteorologists predicted that the system would affect over 100 million people in the United States. The storm brought cold air, heavy snowfall, blowing snow, and mixed precipitation on a path from New Mexico and northern Texas to New England and Eastern Canada. The Chicago area saw 21.2 inches (54 cm) of snow and blizzard conditions, with winds of over 60 mph (100 km/h). With such continuous winds, the blizzard continued to the north and affected Eastern and Atlantic Canada. Blizzard conditions affected many other large cities along the storm's path, including Tulsa, Oklahoma City, Kansas City, St. Louis, Springfield, El Paso, Las Cruces, Des Moines, Milwaukee, Detroit, Indianapolis, Dayton, Cleveland, New York City, New York's Capital District, and Boston. Many other areas not normally used to extreme winter conditions, including Albuquerque, Dallas and Houston, experienced significant snowfall or ice accumulation. The central Illinois National Weather Service in Lincoln, Illinois, issued only their fourth blizzard warning in the forecast office's 16-year history. Snowfall amounts of 20 to 28 inches were forecast for much of Northern and Western Illinois.
The 2011 Halloween nor'easter, sometimes referred to as "Snowtober," "Shocktober," "Storm Alfred," and "Oktoberblast," was a large low pressure area that produced unusually early snowfall across the northeastern United States and the Canadian Maritimes. It formed early on October 29 along a cold front to the southeast of the Carolinas. As it moved up the East Coast, its associated snowfall broke records in at least 20 cities for total accumulations, resulting in a rare "white Halloween" two days later.
The March 2014 North American winter storm, also unofficially referred to as Winter Storm Titan, was an extremely powerful winter storm that affected much of the United States and portions of Canada. It was one of the most severe winter storms of the 2013–14 North American winter storm season, storm affecting most of the Western Seaboard, and various parts of the Eastern United States, bringing damaging winds, flash floods, and blizzard and icy conditions.
The 2017–18 North American winter saw weather patterns across North America that were very active, erratic, and protracted, especially near the end of the season, resulting in widespread snow and cold across the continent during the winter. Significant events included rare snowfall in the South, an outbreak of frigid temperatures that affected the United States during the final week of 2017 and early weeks of January, and a series of strong nor'easters that affected the Northeastern United States during the month of March. In addition, flooding also took place during the month of February in the Central United States. Finally the winter came to a conclusion with a powerful storm system that caused a tornado outbreak and blizzard in mid-April. The most intense event, however, was an extremely powerful cyclonic blizzard that impacted the Northeastern United States in the first week of 2018. Similar to the previous winter, a La Niña was expected to influence the winter weather across North America.
The January 2018 North American blizzard caused widespread severe disruption and blizzard conditions across much of the East Coasts of the United States and Canada in early January 2018. The storm dropped up to 2 feet of snow in the Mid-Atlantic states, New England, and Atlantic Canada, while areas as far south as southern Georgia and far northern Florida had brief wintry precipitation, with 0.1 inches of snow measured officially in Tallahassee, Florida. The storm originated on January 3 as an area of low pressure off the coast of the Southeast. Moving swiftly to the northeast, the storm explosively deepened while moving parallel to the Eastern Seaboard, causing significant snowfall accumulations. The storm received various unofficial names, such as Winter Storm Grayson, Blizzard of 2018 and Storm Brody. The storm was also dubbed a "historic bomb cyclone".
The March 1–3, 2018 nor'easter caused major impacts as well as significant coastal flooding in the Northeastern, Mid-Atlantic and Southeastern United States. It originated as the northernmost low of a stationary front over the Midwest on March 1, which moved eastward into the Northeast later that night. A new low pressure system rapidly formed off the coast on March 2 as it slowly meandered near the coastline. It peaked later that day and brought hurricane-force winds to coastal New England before gradually moving out to sea by March 3. Producing over 2 feet (24 in) of snow in some areas, it was one of the most significant March snowstorms in many areas, particularly in Upstate New York. In other areas, it challenged storm surge records set by other significant storms, such as Hurricane Sandy. It was unofficially named Winter Storm Riley by The Weather Channel.
The 2018–19 North American winter was unusually cold within the Northern United States, with frigid temperatures being recorded within the middle of the season. Several notable events occurred, such as a rare snow in the Southeast in December, a strong cold wave and several major winter storms in the Midwest, and upper Northeast and much of Canada in late January and early February, record snowstorms in the Southwest in late February, deadly tornado outbreaks in the Southeast and a historic mid-April blizzard in the Midwest, but the most notable event of the winter was a record-breaking bomb cyclone that affected much of the Central United States and Canada in mid-March. Unlike previous winters, a developing weak El Niño was expected to influence weather patterns across North America. Overall, however, winter of 2018–19 was mild along the mid- and lower parts of the East Coast, the West Coast, and most of the southern Plains. Overall, the meteorological winter of 2018-19 became the wettest on record for the United States.
Tropical Storm Sanba, known in the Philippines as Tropical Storm Basyang, was a weak tropical cyclone that affected southern and central parts of the Philippines in mid-February 2018. Sanba developed as a tropical depression in the open Pacific Ocean on February 8. The system moved generally westward while slowly developing, finally attaining tropical storm status on February 11. Soon after, wind shear caused the system to lose organization and remain as a minimal tropical storm through February 11 and 12. During this time, Sanba moved westwards then west-northwestwards, making landfall over northeastern Mindanao on February 13. The system weakened into a tropical depression before making another landfall in southeastern Negros later that day. After traversing the Philippine Islands, Sanba failed to reorganize significantly in the Sulu Sea and dissipated two days later west of Palawan.
The April 2019 North American blizzard was a historic blizzard that occurred in the month of April in the Great Plains and the Midwest. As strong winds and heavy snowfall were anticipated to produce widespread reductions in visibility, a blizzard warning was issued from northeastern Colorado to southwestern Minnesota, including several large cities. Denver, Cheyenne, Mitchell and Kearney were all included. Winds gusted as high as 107 mph (172 km/h) at Pueblo West and more than 30 inches of snow fell in Wallace, South Dakota.
Typhoon Kammuri, known in the Philippines as Typhoon Tisoy, was a powerful typhoon which impacted the Philippines in early December 2019. Kammuri, which means crown or Corona Borealis in Japanese, the twenty-eighth named storm and sixteenth typhoon of the 2019 Pacific typhoon season, Kammuri developed from a tropical wave situated a couple hundred kilometers south of the Mariana Islands. From November 25 to 27, the system tracked westward at a steady pace and rate of intensification, first making minor impacts in Guam. On November 28, the system intensified into a typhoon as environmental conditions became marginally conducive for significant development. From November 29 to December 1, Kammuri was unable to strengthen to previous estimates due to its near stationary movement as a result of weak steering currents, upwelling itself consequently. On December 2, the system tracked westward at a much faster speed of 19 km/h (12 mph) and rapidly intensified over warm Philippine Sea waters, before making landfall in the Bicol Region of the Philippines at peak intensity as a category 4-equivalent typhoon.
Typhoon Vamco, known in the Philippines as Typhoon Ulysses, was a powerful and very destructive Category 4-equivalent typhoon that struck the Philippines and Vietnam. It also caused the worst flooding in Metro Manila since Typhoon Ketsana in 2009. The twenty-second named storm and tenth typhoon of the 2020 Pacific typhoon season, Vamco originated as a tropical depression northwest of Palau, where it slowly continued its northwest track until it made landfall in Quezon. After entering the South China Sea, Vamco further intensified in the South China Sea until it made its last landfall in Vietnam.
The Tropical Cyclone Wind Signals are tropical cyclone alert levels issued by the Philippine Atmospheric, Geophysical, and Astronomical Services Administration (PAGASA) to areas within the Philippines that may be affected by tropical cyclone winds and their associated hazards.
Severe Tropical Storm Ma-on, known in the Philippines as Severe Tropical Storm Florita, was a tropical cyclone that impacted the Philippines in August 2022. The ninth named storm of the 2022 Pacific typhoon season, Ma-on originated as a disturbance over in the Pacific Ocean on August 18, and was upgraded to a tropical depression during the next day. The depression strengthened into a tropical storm receiving the name Ma-on, and became a severe tropical storm late on August 23 before making landfall in the Philippines. It would later make landfall in China and Vietnam on August 25. Ma-on weakened back to a tropical depression and due to unfavorable conditions it dissipated on August 26, 2022.
A late-season tornado outbreak in the Southern United States affected the states of Louisiana, Mississippi, Alabama, and Georgia, from the afternoon of November 29 into the morning of November 30, 2022. The outbreak was the result of an intense upper-level trough that materialized over the aforementioned states where increased moisture, atmospheric instability, and elevated wind shear were present, creating conditions highly conducive to supercell thunderstorms. Multiple tornadic storms developed in the risk area, producing numerous tornadoes. Several of these tornadoes were strong and destructive, prompting the issuance of multiple PDS tornado warnings. Two low-end EF3 tornadoes caused severe damage near Clarks, Louisiana and Tibbie, Alabama respectively while the Flatwood and Willow Springs communities north of Montgomery, Alabama was struck by an EF2 tornado, which caused two fatalities. Numerous weaker tornadoes also touched down, including a high-end EF1 tornado that caused considerable damage in Eutaw, Alabama. In all, 25 tornadoes were confirmed.
Ohio school districts can use five calamity days before they must start adding extra days to the school calendar.