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SSC Weather Station

24 hour graph

Wind strength and direction: red=gusts, green=lulls, black=15 minute average.
If points are tightly bunched, wind is constant; if they are widely spaced, wind is gusty.
Symbols across the top which look like the tracks of a drunken seagull represent the wind direction.

1 hour graph

As above, but the black points and line represent 5 minute averages

Please, please, if you have any ideas of what you would like to see here and how the data might be displayed to best effect, contact me! This will become the main page for Slaughden Quay and you have a chance to influence it (but not the weather itself, unfortunately!)

The anemometer is not of the usual rotating vane type, but is a solid state ultrasonic device. On a pole over the clubhouse door you will see a thing like a black cake tin. This contains four ultrasonic transducers which take it in turns to squeak. The other three listen for the squeak and report back to a microprocessor, which uses the time it took the squeak to reach the transducers to work out the speed and direction of the wind blowing through the cake tin.

A PC in the OOD's office gets the information every second and calculates the 10 second average wind speed and direction, which is used by the website to update the display. The PC also maintains a 5 minute rolling average over the period of the last hour, used to update the hourly wind graph. And finally a 15 minute rolling average is calculated over the last 24 hour period, used this time to update the day graph.

Finally, it is a good job that information isn't subject to air miles. When you point your web browser at the SSC site, the display is loaded from near Dallas, Texas (where our web host has their server farm). Part way through this process the server receives an instruction to get the current weather data from the SSC weather station in Slaughden. This is sent back to Dallas to complete the page and then processed and sent to your PC for display. Four trips across the Atlantic for your delectation!