Weather Underground allows you to browse through local weather stations, including the "official" ones (like airports, etc.).
And n3kl.org to get the estimate Kp Index to assess the likelihood of unreliable GPS. There is also an archive on this page so you can look back if you have GPS/Position Hold problems and see whether there was a coronal mass ejection that could have caused it. Andy
I forgot to mention this site -- it ties it all together: http://www.uavforecast.com/#/ It used to be entirely free but has now gone subscription for more than two days of forecast -- can't say I blame whoever runs it as I'm sure it took/takes a fair amount of time to operate. Andy