weather station

Weather station at Mildura Airport, Victoria, Australia.

A weather station is a facility with instruments and equipment to make observations of atmospheric conditions in order to provide information to make weather forecasts and to study the weather and climate. The measurements taken include temperature, barometric pressure, humidity, wind speed, wind direction, and precipitation amounts. Wind measurements are taken as free of other obstructions as possible, while temperature and humidity measurements are kept free from direct solar radiation, or insolation. Manual observations are taken at least once daily, while automated observations are taken at least once an hour.

Instruments

A technician examines a weather station's anemometer.

Typical weather stations have the following instruments:

• Thermometer for measuring temperature
• Barometer for measuring barometric pressure/air pressure
• Hygrometer for measuring humidity
• Anemometer for measuring wind speed
• Wind vane for measuring wind direction
• Rain gauge for measuring precipitation^[1]

Exposure

Except for those instruments requiring direct exposure to the elements (anemometer, rain gauge), the instruments should be sheltered in a vented box, usually a Stevenson screen, to keep direct sunlight off the thermometer and wind off the hygrometer. The instrumentation may be specialized to allow for periodic recording otherwise significant manual labour is required for record keeping. Automatic transmission of data, in a format such as METAR, is also desirable as many weather station's data is required for weather forecasting.

Daily observation times

Historically, readings were taken by unpaid weather observers, performing the duty as part of their permanent jobs, e.g., postmaster. These weather readings were taken between 7 and 9 a.m. local time daily, as unpaid observers were unwilling to take more frequent readings from midnight to midnight. Since the advent of automatic weather stations, such as automated airport weather stations and personal weather stations, surface weather observations are taken hourly, or more frequently.

Networks

A variety of weather station networks have been set up globally. Some of these are basic to analyzing weather fronts and pressure systems, such as the synoptic observation network, while others are more regional in nature.

Global

• Citizen Weather Observer Program^[2]
• Weather Underground Personal Weather Stations^[3]

United States

• Arizona Meteorological Network (AZMET)^[4]
• Central Pennsylvania Volunteer Weather Station Network^[5]
• Florida Automated Weather Network (FAWN)^[6]
• Georgia Environmental Monitoring Network (GAEMN)^[7]
• Indiana Purdue Automated Agricultural Weather Station Network (PAAWS)^[8]
• MesoWest^[9]
• Michigan Automated Weather Network (MAWN)^[10]
• Missouri Weather Stations^[11]
• National Weather Service Cooperative Observer Program^[12]
• Oklahoma Mesonet^[13]
• The Pacific Northwest Cooperative Agricultural Weather Network^[14]

Southern Hemisphere

• Antarctic Automatic Weather Stations Project^[15]
• Australia/Bureau of Meteorology AWS network.^[16]
• Australia/Department of Agriculture and Food Western Australia^[17]
• Australia/Lower Murray Water Automatic Weather Station Network^[18]

References

See also

• Global Telecommunications System
• Weather buoy
• Weather satellite
• Weather ship

External links

Wikimedia Commons has media related to: Category:Weather stations

• International Weather Watchers Observer Handbook (PDF 768KB 45 pages)
• Association of American Weather Observers
• Citizen Weather Observer Program
• CWOP Weather Station Siting, Performance, and Data Quality Guide (PDF 800KB 88 pages)
• Initial Guidance to Obtain Representative Meteorological Observations at Urban Sites, by Tim R. Oke (PDF 423KB 51 pages)
• NWS Cooperative Observer Program
• NWS Observing Handbook No. 2: Cooperative Station Observations (PDF 1.4MB 94 pages)