This has been going on for a long time now, probably several months, at least.
During my daytime the connection to HTC servers is fine, but at about 18:00 (CEST) / 11am CDT it's starting to get wonky. From about 19:00 (CEST) / 12pm CDT on the ping goes from ~140 to 200-240, get high variance, lots of packet loss too. This keeps on until between 22:00-23:00 / 3pm-4pm CDT, when first the ping starts to get better and later on the connection get's more stable again. The resulting warpfest makes plaing at Euro prime a non option for me.
I tried to trace to a few other servers in the general area. Those taking entirely different routes were totally fine, for example to dallas1up.monitis.com. When I found one using a similar route (through frontier.net network), I would get the same bad results as I did with HTC servers.
Randomly chosen European servers are fine. While I do use a WLAN, I also tested using a network cable, with similar results.