Weather Underground (weather service)

Found the Weather Underground weather service today and it looks really great:

http://www.wunderground.com/
http://en.wikipedia.org/wiki/Weather_Underground_(weather_service)

One thing I like--it keeps historical data. For other sites like AccuWeather and Weather Channel, it seems quite impossible to find historical data, even for the previous day!

It also seems quite democratic--they include weather data from anyone with the means to purchase and maintain a small weather station kit. Quite exciting.

Also, too, the WunderMap: http://www.wunderground.com/wundermap/