This site provides useful practical information related to global and national weather observing practices and instruments, including independent equipment reviews.
You will find much of the background in my new book The Weather Observer’s Handbook (Cambridge University Press, 2012), details of which can also be found on this site, together with useful links and downloads.
Author, The Weather Observer’s Handbook
A nation obsessed with the weather? Yes, certainly, but which nation?
Tip of The Day
A good exposure for one sensor can be the exact opposite for another. For representative wind speed and direction readings, for example, an anemometer mounted on top of a tall mast in a very open expanse is ideal, but this would be a poor exposure for a raingauge owing to wind effects. No single exposure will provide a perfect fit for the requirements of all sensors.
The units of atmospheric pressure are hectopascals (hPa) – a hectopascal is numerically identical to the more familiar millibar. Inches of mercury are still used for some public weather communications within the United States – one inch of mercury is 33.86 hPa.
The ideal site for wind instruments is atop a 10 m mast in open, level terrain, well away from any obstacles. However, such ideal sites are hard to come by, particularly in urban or suburban areas, and wind records are therefore necessarily more site-specific than most other weather measurements. Some corrections for the variation of mean wind speed with height are possible, and these are described in The Weather Observer's Handbook. Gust speeds should not be corrected.
‘Humidity’ refers to the amount of water vapour in the air, a vital component of the weather machine. Various measures are used to quantify the amount of atmospheric water vapour – relative humidity and dew point being the two most commonly used. Knowledge of any two values can derive other humidity parameters. The amount of water vapour that the air can hold varies significantly with temperature – saturated air at 0 °C holds only a quarter of the amount that saturated air at 20 °C can hold.
AWS software provides three key functions – system setup and configuration, communication with and downloading of data from the datalogger, and the display of current and logged data. Most offer some form of data upload to Internet/website.