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 book The Weather Observer’s Handbook (published by Cambridge University Press), 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
By convention, 24 hour minimum temperatures read at the morning observation are entered to the day on which they were read, whereas 24 hour maximum temperature and total rainfall are entered to the day prior to the observation (they are said to be ‘thrown back’).
Snowfall is difficult to measure accurately with most types of raingauge, and without some form of wind shield most raingauges will lose 50 per cent or more of the ‘true’ catch through wind errors introduced by the presence of the gauge, which interferes with the flow of the wind over it, causing a loss of some of the catch.
Instrument calibrations are one of the most important, yet also one of the most neglected, areas of weather measurement. Making accurate weather measurements requires accurately calibrated instruments.
Radiation from the Sun consists of a wide range of wavelengths, from extreme ultraviolet to the far infrared, peaking in the visible region. Solar radiation is amongst the most variable of all weather elements, and consists of two main components – direct solar radiation from the solar disk, and diffuse solar radiation from the rest of the sky, the latter as a result of the scattering and reflection of the direct beam in its passage through the atmosphere.
Recording raingauges can be easily and accurately calibrated by passing a known volume of water through the gauge, and comparing with the indicated measurement. ‘Out of the box’ errors for some AWS tipping-bucket raingauges of this type can exceed 20 per cent, so this is a vital test for all new instruments at first installation. Recording raingauges should not be adjusted merely to attempt exact agreement, or near-agreement, with a standard raingauge, because instrumental and exposure differences inevitably lead to slight variations in the amount of rainfall recorded.