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| Home || Weather Learning Programs | Instruments | SafeSun Sensor |
Making a Weather Station |
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Features |
| The elements usually observed and recorded in a home or school weather station are: |
 Dry bulb temperature. Thermometers must be housed in an
instrument enclosure (see the plans (Plan 1, Plan 2,
Plan 3) in Section 3). An official enclosure is called a Stevenson screen. |
| Wet bulb temperature |
| Rainfall - standard 203mm collector. The rain gauge can be
attached to the instrument enclosure. |
| Surface wind direction and velocity. Use a simple wind vane,
correctly oriented. The vane should be about 10 metres above ground level. A relatively inexpensive, hand-held
Venturi meter can be used to determine wind speed. |
| Estimate of surface (horizontal) visibility. |
| Noting phenomena such as hail and severe squalls. |
| Barometric pressure. A dial-type aneroid barometer is
appropriate. |
| Terrestrial (ground) minimum temperature. The lowest temperature
reached overnight at grass level is referred to as the terrestrial minimum temperature. This is measured on a separate
minimum thermometer, re-set and placed on the grass at, say, the 3pm observation, read at the 9am observation, and left
in the screen for safety during the day |
| Autographic records. Continuous readings of air temperature and humidity
charted against a time scale can be obtained from thermographs, hygrographs, or thermo-hygrographs. The "weekly" types
are most suitable, requiring a chart change once a week. |
| A range of meteorological instruments suitable for amateur use are stocked by those companies listed previously and others. |
| It is almost impossible to select a site for an instrument enclosure in city and suburban areas that satisfies the strict criteria imposed on official observation sites. But be prepared to compromise, and try to find a grassed area as far away from buildings, trees and fences as possible. Where security is a problem, consider erecting a high fence with a locked gate. The site should be about 10 metres by 10 metres, but the dictates of space and finance may necessitate something smaller. |
| Observations are generally made every three hours, from 3am to 9pm, but most climate stations make observations twice a day, at 9am and 3pm. This is sufficient to establish the average values of various elements - such as rainfall and temperature - for a district. |
Further information: |
| The Observations Section, Victorian Regional Office Bureau of Meteorology, Level 11, 700 Collins Street (GPO Box 1636M), DOCKLANDS VIC 3008 tel: 9669 4950, 9669 4951 or 9669 4952 (8.30am-5pm, Monday to Friday) e-mail: j.cornall-reilly@bom.gov.au |