National severe weather warning service
Encyclopedia
The National Severe Weather Warning Service (shortened NSWWS) is a service produced by the UK Met Office which informs the public of the United Kingdom
of severe weather
which may damage the country's infrastructure
and endanger lives. It is required for two main reasons; to inform the Ministry of Defence
and civil emergency authorities to trigger plans to help protect the public; and to alert the public to make necessary preparations for the weather
event, mostly through the media.
that may occur in the next 5 days, while Flash warnings are warnings of severe or extreme weather
that may occur in the next few hours.
improved its warning system by adding an extra stage of warning, the 'Advisory'. They have also provided more colours for different stages of warnings to try to make the system clearer for the public.
Severe weather
Green = No warnings issued
Yellow = Moderate risk of severe weather
; moderate risk of disruption
Amber (Early) = High risk of severe weather
; high risk of disruption
Amber (Flash) = Severe weather
is imminent or occurring/expected in the next few hours; very high risk of disruption
Extreme weather
Green = No warnings issued
Yellow = Low risk of extreme weather
; low risk of major disruption
Amber = Moderate risk of extreme weather
; moderate risk of major disruption
Red (Early) = High risk of extreme weather
; high risk of major disruption
Red (Flash) = Extreme weather
is imminent or occurring; very high risk of major disruption and COBRA
may be involved if in a highly populated area, such as London
Warning, under the recent improvements. The other new tier of alert, the Advisory, is associated with the colour yellow and just indicates that the public should be aware of potential severe weather
by ensuring they have access to the latest weather forecast.
primarily use the broadcast media to inform the public of any warnings. The BBC
, ITV
and Channel 4
are the terrestrial networks that use the Met Office's data, so are the ones that broadcast the warnings (usually through their television
services, although the BBC
use their radio stations
and website
as well). In some cases, news companies can also be informed, especially for extreme weather, which can also advise the public of what to do.
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
of severe weather
Severe weather
Severe weather phenomena are weather conditions that are hazardous to human life and property.- Examples Include :Severe weather can occur under a variety of situations, but three characteristics are generally needed: a temperature or moisture boundary, moisture, and , instability in the...
which may damage the country's infrastructure
Infrastructure
Infrastructure is basic physical and organizational structures needed for the operation of a society or enterprise, or the services and facilities necessary for an economy to function...
and endanger lives. It is required for two main reasons; to inform the Ministry of Defence
Ministry of Defence (United Kingdom)
The Ministry of Defence is the United Kingdom government department responsible for implementation of government defence policy and is the headquarters of the British Armed Forces....
and civil emergency authorities to trigger plans to help protect the public; and to alert the public to make necessary preparations for the weather
Weather
Weather is the state of the atmosphere, to the degree that it is hot or cold, wet or dry, calm or stormy, clear or cloudy. Most weather phenomena occur in the troposphere, just below the stratosphere. Weather refers, generally, to day-to-day temperature and precipitation activity, whereas climate...
event, mostly through the media.
Types of warnings
There can be different types of warnings, depending on the severity of the event. Early warnings are warnings of severe or extreme weatherExtreme weather
Extreme weather includes weather phenomena that are at the extremes of the historical distribution, especially severe or unseasonal weather. The most commonly used definition of extreme weather is based on an event's climatological distribution. Extreme weather occurs only 5% or less of the time...
that may occur in the next 5 days, while Flash warnings are warnings of severe or extreme weather
Extreme weather
Extreme weather includes weather phenomena that are at the extremes of the historical distribution, especially severe or unseasonal weather. The most commonly used definition of extreme weather is based on an event's climatological distribution. Extreme weather occurs only 5% or less of the time...
that may occur in the next few hours.
Improvements
As of March 2008, the Met OfficeMet Office
The Met Office , is the United Kingdom's national weather service, and a trading fund of the Department for Business, Innovation and Skills...
improved its warning system by adding an extra stage of warning, the 'Advisory'. They have also provided more colours for different stages of warnings to try to make the system clearer for the public.
Severe weather
Green = No warnings issued
Yellow = Moderate risk of severe weather
Severe weather
Severe weather phenomena are weather conditions that are hazardous to human life and property.- Examples Include :Severe weather can occur under a variety of situations, but three characteristics are generally needed: a temperature or moisture boundary, moisture, and , instability in the...
; moderate risk of disruption
Amber (Early) = High risk of severe weather
Severe weather
Severe weather phenomena are weather conditions that are hazardous to human life and property.- Examples Include :Severe weather can occur under a variety of situations, but three characteristics are generally needed: a temperature or moisture boundary, moisture, and , instability in the...
; high risk of disruption
Amber (Flash) = Severe weather
Severe weather
Severe weather phenomena are weather conditions that are hazardous to human life and property.- Examples Include :Severe weather can occur under a variety of situations, but three characteristics are generally needed: a temperature or moisture boundary, moisture, and , instability in the...
is imminent or occurring/expected in the next few hours; very high risk of disruption
Extreme weather
Green = No warnings issued
Yellow = Low risk of extreme weather
Extreme weather
Extreme weather includes weather phenomena that are at the extremes of the historical distribution, especially severe or unseasonal weather. The most commonly used definition of extreme weather is based on an event's climatological distribution. Extreme weather occurs only 5% or less of the time...
; low risk of major disruption
Amber = Moderate risk of extreme weather
Extreme weather
Extreme weather includes weather phenomena that are at the extremes of the historical distribution, especially severe or unseasonal weather. The most commonly used definition of extreme weather is based on an event's climatological distribution. Extreme weather occurs only 5% or less of the time...
; moderate risk of major disruption
Red (Early) = High risk of extreme weather
Extreme weather
Extreme weather includes weather phenomena that are at the extremes of the historical distribution, especially severe or unseasonal weather. The most commonly used definition of extreme weather is based on an event's climatological distribution. Extreme weather occurs only 5% or less of the time...
; high risk of major disruption
Red (Flash) = Extreme weather
Extreme weather
Extreme weather includes weather phenomena that are at the extremes of the historical distribution, especially severe or unseasonal weather. The most commonly used definition of extreme weather is based on an event's climatological distribution. Extreme weather occurs only 5% or less of the time...
is imminent or occurring; very high risk of major disruption and COBRA
Cabinet Office Briefing Rooms
Cabinet Office Briefing Room is a term used to describe the formation of a crisis response committee, coordinating the actions of bodies within the government of the United Kingdom in response to instances of national or regional crisis, or during events abroad with major implications for the UK...
may be involved if in a highly populated area, such as London
London
London is the capital city of :England and the :United Kingdom, the largest metropolitan area in the United Kingdom, and the largest urban zone in the European Union by most measures. Located on the River Thames, London has been a major settlement for two millennia, its history going back to its...
New tiers of alert
Previously, in exceptional circumstances where extremely damaging weather would have occurred, an Emergency Flash Warning would have been issued, for example when a major storm hit Scotland in January 2005. This has now been replaced by the Extreme WeatherExtreme weather
Extreme weather includes weather phenomena that are at the extremes of the historical distribution, especially severe or unseasonal weather. The most commonly used definition of extreme weather is based on an event's climatological distribution. Extreme weather occurs only 5% or less of the time...
Warning, under the recent improvements. The other new tier of alert, the Advisory, is associated with the colour yellow and just indicates that the public should be aware of potential severe weather
Severe weather
Severe weather phenomena are weather conditions that are hazardous to human life and property.- Examples Include :Severe weather can occur under a variety of situations, but three characteristics are generally needed: a temperature or moisture boundary, moisture, and , instability in the...
by ensuring they have access to the latest weather forecast.
Media use
The Met OfficeMet Office
The Met Office , is the United Kingdom's national weather service, and a trading fund of the Department for Business, Innovation and Skills...
primarily use the broadcast media to inform the public of any warnings. The BBC
BBC
The British Broadcasting Corporation is a British public service broadcaster. Its headquarters is at Broadcasting House in the City of Westminster, London. It is the largest broadcaster in the world, with about 23,000 staff...
, ITV
ITV
ITV is the major commercial public service TV network in the United Kingdom. Launched in 1955 under the auspices of the Independent Television Authority to provide competition to the BBC, it is also the oldest commercial network in the UK...
and Channel 4
Channel 4
Channel 4 is a British public-service television broadcaster which began working on 2 November 1982. Although largely commercially self-funded, it is ultimately publicly owned; originally a subsidiary of the Independent Broadcasting Authority , the station is now owned and operated by the Channel...
are the terrestrial networks that use the Met Office's data, so are the ones that broadcast the warnings (usually through their television
Television
Television is a telecommunication medium for transmitting and receiving moving images that can be monochrome or colored, with accompanying sound...
services, although the BBC
BBC
The British Broadcasting Corporation is a British public service broadcaster. Its headquarters is at Broadcasting House in the City of Westminster, London. It is the largest broadcaster in the world, with about 23,000 staff...
use their radio stations
BBC Radio
BBC Radio is a service of the British Broadcasting Corporation which has operated in the United Kingdom under the terms of a Royal Charter since 1927. For a history of BBC radio prior to 1927 see British Broadcasting Company...
and website
Bbc.co.uk
BBC Online is the brand name and home for the BBC's UK online service. It is a large network of websites including such high profile sites as BBC News and Sport, the on-demand video and radio services co-branded BBC iPlayer, the pre-school site Cbeebies, and learning services such as Bitesize...
as well). In some cases, news companies can also be informed, especially for extreme weather, which can also advise the public of what to do.