Weather undergrounds Other current weather information

Weather undergrounds are sites providing inter- active programs that operate at a variety of sites in the USA, using a menu-based system by which the user can browse though a wealth of textual information about the weather (inclu- ding tabulated reports, severe weather warn- ings, ski reports, etc.) and related phenomena. Although most of this information concerns North American weather, some international reports may be obtained (often in the form of the ‘place name, temperature, weather type’ lunchtime weather reports to be found in the national daily newspapers). Try connecting to the URLS telnet://downwind.sprl.umich. edu:3000 (at the University of Michigan) or telnet://thunder.met.fsu.edu:3OOO (at Flor- ida State University) -no passwords are needed. (When accessing these sites directly using telnet, include the ‘:3000’ as part of the remote site name.)

There are a variety of other servers around the world that provide information about local weather. For example, telnet://vicbeta. vic.bom.gov.au:55555 (provided by the Melbourne Bureau of Meteorology) is a menu- based service providing weather details from south-east Australia, while the South African Weather Bureau (urn http://cirrus. sawb.gov.za/observationlobs.html) pro- vides details of current weather in South Africa.

Note

Because of the typesetting conventions used in this article, some spaces have appeared in the urns. These should not be included when typ- ing them.

Reference Brugge, R. (1994) Computer networks and meteorologi-

cal information. Weather, 49, pp. 298-306

Readers’ Forum Readers are invited to contribute short questions on any meteorological topic. We will endeavour to obtain an- swers to all submitted questions.

Why castellanus? The castellated form of altocumulus cloud once known as castellatus to describe its turreted ap- pearance (which seemed to be very appropriate) was last used as far as I am aware in the Meteorolo- gical Office’s Observer’s handbook, published in 1952. Ludlam and Scorer in their Cloud study - a pictorial guide, prepared under the auspices of the Royal Meteological Society and published in 1957, used castellanus. This has evidently come to be ac- cepted as the official description. I would be in- terested to know why the change was made and on whose authority.

Cardigan, Dyfed

David Booth

Nick Grahame replies: It certainly appears that the change in spelling was discussed in the early 1950s at a high level. Any indecision at that stage may explain why the Hand- book of weather messages, published in 1954

by the Meteorological Office, simply described the cloud form without any reference to either cas- tellanus or castellatus. The definitive shift to the use of castellanus appears to take place in the W M O cloud atlas, published in 1956. Since then, other publications, such as the Observer’s handbook, have followed suit. However, I did find a reference to castellatus in Spacious skies by Scorer and Verkaik, published in 1989.

The question of why the change was made is open to some speculation. There is no doubt that castellanus is correct according to a Latin diction- ary. So I can only suggest that the cloud type was named in error initially and that the error was recti- fied when this was realised. My thanks go to Mick Wood and Maurice Crewe at the Meteorological Office for their help in investigating this matter.

The declining frequency of snow in south- ern England For the eighth consecutive year January has been virtually snowless in this part of England. During the last 26 years (1970-95) the number of days here with sleet or snow falling in January has aver- aged 3.7 - in the last eight of these (1988-95)

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