For the UKMET model, see: Tropical cyclone forecast model.

The Met Office (originally an abbreviation for Meteorological Office, but now the official name in itself), which has its headquarters at Exeter in Devon, is the United Kingdom's national weather service and a subsidiary of the Ministry of Defence. Part of the Met Office complex in Exeter is the Met Office College, which handles the training for internal personnel and many forecasters from around the world. The current chief executive is John Hirst who replaced Mark Hutchinson on 17 September, 2007.

History

Established in 1854 as a small department within the Board of Trade under Robert FitzRoy as a service to mariners. The loss of the passenger vessel the Royal Charter and 459 lives off the coast of Anglesey in a violent storm in October 1859 led to the first gale warning service. In 1861 FitzRoy had established a network of 15 coastal stations from which visual gale warnings could be provided for ships at sea.

The development of the electric telegraph in the 1870's led to the more rapid dissemination of warnings and also led to the development of an observational network which could then be used to provide synoptic analyses.

In 1879 the Met Office started providing forecast to Newspapers.

Following the First World War the Met Office later became part of the Air Ministry in 1920. In 1936 the Met Office split with services to the Royal Navy being provided by their own forecasting services.

It currently holds a quasi-governmental role, being required to act commercially but also remaining an executive agency of the Ministry of Defence. A little known branch of the Met Office known as the Mobile Met Unit (MMU) accompany forward units in times of conflict advising the armed forces of the prevailing conditions for battle, particularly the RAF. The Hadley Centre for Climate Prediction and Research is also part of the Met Office.

Locations

In 2003 the Met Office moved its headquarters to Exeter, in Devon from its previous location of Bracknell in Berkshire and it has a worldwide presence including a forecasting centre in Aberdeen and offices in Gibraltar and on the Falklands. Other outposts lodge in establishments such as the Joint Centre for Mesoscale Meteorology (JCMM) at University of Reading in Berkshire, the Joint Centre for Hydro-Meteorological Research (JCHMR) site at Wallingford in Oxfordshire and there is also a Met Office presence at many Army and Air Force bases within the UK and abroad. Royal Navy weather forecasts are generally provided by naval officers, not Met Office personnel.

Forecasts

The Shipping Forecast

One of the British stalwarts the Shipping Forecast is produced by the Met Office and broadcast on BBC Radio 4. The Shipping Forecast has long been of real interest to, and vital to the safety of, Mariners traversing the Sea Areas around the British Isles and its broadcast on radio is still avidly listened to. Less vitally, the Shipping Forecast has been the subject of both books and song lyrics.

Weather Forecasting and Warnings

At the Met Office, they have the responsibility to issue severe weather warnings for the United Kingdom through the National Severe Weather Warning Service (NSWWS). These are weather events that may affect transport infrastructure and endanger people's lives. In March 2008, the system was improved and a new stage of warning was introduced, the 'Advisory'.

Their main role is to produce forecast models by gathering all the information from satellites in space and observations on earth, then processing it using supercomputers which produce a variety of models, collectively known as the Unified Model. If necessary, forecasters may then make adjustments to the forecasts. This main bulk of data is then passed on to companies who acquire it. In particular, two of the main media companies, the BBC and ITV produce forecasts using the Met Office's data. At the BBC Weather Centre, they are continuously updated on the latest information arriving by computer, or by fax and e-mail. The BBC's new graphics are used on all of their television weather broadcasts, but ITV use animated weather symbols. This is mainly how the public are informed of weather events which may affect day-to-day life.

World Area Forecast Centre

The Met Office is also one of only two World Area Forecast Centres or WAFCs, and is referred to as WAFC London. The other WAFC is located in Missouri, USA but known as WAFC Washington. WAFC data are used daily to safely and economically route aircraft, particularly on long-haul journeys. The data provide details of wind speed and direction, air temperature, cloud type and tops, and other features of interest to the aviation community, such as volcanic ash eruptions.

Air Quality

The Met Office issues air quality forecasts made using NAME, the Met Office's medium-to-long-range atmospheric dispersion model. It was originally developed as a nuclear accident model following the Chernobyl accident in 1986, but has since evolved into an all-purpose dispersion model capable of predicting the transport, transformation and deposition of a wide class of airborne materials. NAME is used operationally by the Met Office as an emergency response model as well as for routine air quality forecasting.

In the air quality forecasts, the level of pollution is described either as an index (ranging from 1 to 10) or as a banding (low, moderate, high or very high). These levels are based on the health effects of each pollutant as shown just below.

Index	Banding	Health Effect
1–3	Low	Effects are unlikely to be noticed even by individuals who know they are sensitive to air pollutants.
4–6	Moderate	Mild effects, unlikely to require action, may be noticed amongst sensitive individuals.
7-9	High	Significant effects may be noticed by sensitive individuals and action to avoid or reduce these effects may be needed (e.g. reducing exposure by spending less time in polluted areas outdoors). Asthmatics will find that their 'reliever' inhaler is likely to reverse the effects on the lung.
10	Very High	The effects on sensitive individuals described for 'High' levels of pollution may worsen.

The forecast is produced for a number of different pollutants and their typical health effects are shown in the following table.

Pollutant	Health Effects at High Level
Nitrogen dioxide Ozone Sulphur dioxide	These gases irritate the airways of the lungs, increasing the symptoms of those suffering from lung diseases.
Particulates	Fine particles can be carried deep into the lungs where they can cause inflammation and a worsening of heart and lung diseases

High Performance Computing

Due to the large amount of computation needed for Numerical Weather Prediction and the Unified model, the Met Office has had some of the most powerful supercomputers in the world. In November 1997 the Met Office supercomputer was ranked third in the world..

Year	Computer	Calculations a second	Horizontal Resolution (Global/local)	Number of Vertical levels
1959	Ferranti Mercury	3Kflops	(N.A./320 km)	2 levels
1965	English Electric KDF9	50Kflops	(N.A./300 km)	3 levels
1972	IBM System/360 195	4Mflops	(300 km/100 km)	10 levels
1982	CDC Cyber 205	200Mflops	(150 km/75 km)	15 levels
1991	Cray Y-MP C90/16	10Gflops	(90 km/17 km)	19 levels
1997	Cray T3E 900/1200	430Gflops	(60 km/12km)	38 levels
2004	NEC SX-6	2.0Tflops	(40km/4km)	50 levels

Weather stations

Reports (observations) from weather stations vary considerably. They can be automatic (totally machine produced), semi-automatic (part-machine and part manual), or manual. Some stations produce manual observations during business hours and revert to automatic observations outside these times. Many stations now also feature recent innovations such as "present weather" sensors, CCTV, etc.

Some stations have limited reporting times, while other report continuously, mainly RAF and Army Air Corps stations where a manned met office is provided for military operations. The "standard" is a once-hourly reporting schedule, but automatic stations can often be "polled" as required, while stations at airfields regularly report twice-hourly, with additional (often frequent in times of bad weather) special reports as necessary to inform airfield authorities of changes to the weather that may affect aviation operations.

Some stations report only CLIMAT data (e.g maximum and minimum temperatures, rainfall totals over a period, etc.) and these are usually recorded at 0900 and 2100 hours daily. Weather reports are often performed by Observers not specifically employed by the Met Office, e.g. Air traffic control staff, Coastguards, University staff, etc.

• Penkridge weather station
• Wye weather station
• RAF Coningsby
• RAF Lossiemouth weather station
• RAF Kinloss weather station
• RAF Leuchars weather station
• RAF Leeming weather station
• RAF Little Rissington weather station (supported by RAF Brize Norton)
• RAF Marham weather station
• RAF Cranwell weather station
• RAF Waddington weather station
• RAF Odiham weather station
• RAF Boulmer weather station
• RAF Brize Norton weather station
• AAC Middle Wallop weather station
• AAC Wattisham weather station

Notable former Directors General and Chief Executives

• Sir William Napier Shaw 1905-1920
• Sir Graham Sutton 1954-1965
• Basil John Mason 1965-1983
• Sir John Houghton 1983-1991
• Julian Hunt 1992-1997
• Peter Ewins 1997-2004
• Dr David Rogers 2004-2005
• Mark Hutchinson 2005-2007
• John Hirst 2007-

See also

• Burns' Day storm
• Climate of the United Kingdom
• Eskdalemuir Observatory
• Great Storm of 1987
• Met Éireann, the Irish meteorological service, which separated from the UK Met Office in 1936.
• North West Shelf Operational Oceanographic System

References

External links

• Met Office homepage
• History of the Met Office
• BBC Weather Centre
• BBC Shipping Forecast page
• Joint Centre for Mesoscale Meteorology at the University of Reading
• Joint Centre for Hydro-Meteorological Research