I have found yahoo weather forcast most helpful.
I'm able to get an hourly weather request here from Yahoo.
How can I make an API request for the above hourly weather report using an Yahoo API call to http://weather.yahooapis.com/forecastrss?w=2502265?
Yahoo Weather Api does not seem to support hourly forecasts, there are just a few parameters you have control over like the location in (woeid) or (lat, long) and the temperature-unit (u or f), refer here for yahoo query language.
You can use other api's AccuWeather for hourly details.