Dear WeatherCat do it yourself types,
Many moons ago, I wrote up how I created a dust cap from a leftover container that held Red Vines licorice. Alas, it seems to have been lost. It might have even predated WeatherCat, so I better recreate it. The container I used is a tub of Red Vines that looks this:
I found that I could use the end of the tub and it fit very snugly over the Davis station collector cone. It turns out you can have the cap no taller than 2-3/8" to provide enough clearance for the solar radiation sensor support:
This is the second such cap I have made. The first one was badly damaged and discolored by the sun:
It eventually became so brittle that it shattered. To avoid this I painted the second one:
To provide it lots of UV protection, I applied 12 coats of paint! It has performed well for several years. All it needs is a little cleaning when it comes back inside from the long dry season.
Of course a cap like this will prevent you from collecting rainfall data should rain fall unexpectedly. Even in California, there are unexpected rainy events in the summer. Still, I carefully monitor the weather forecasts, and when there is any change of rain, I remove the cap. Thanks to my vigilance, I've never missed a bucket tip. If you have a mission critical station, a cap like this would not be permitted. But for the hobbyist it is a welcome way to keep your rain gauge clean, especially if you have extended periods of predictably dry weather.
Cheers, Edouard
P.S.
Red Vines is a product that most likely can only be found in the San Francisco Bay Area. It is produced by the
American Licorice Company only in their Union City plant. However, it is possible that the same sort of container is used for other products in other parts of the country.