The IEM website was very slow or unresponsive between 1-2 PM on Thursday, 16 April 2015. I was sitting in a meeting at the time and did not immediately notice that bad things were happening. The issue was a cascading failure of my tilecache service due to a failure to generate N0R RADAR Composites during this time. The lack of current radar data was causing most of the incoming requests to bypass a caching layer and instead hit the mapserver backend, which was quickly overwhelmed with work.

I have made some changes to hopefully prevent this from happening again, thanks for your patience.