NOAA and other space weather agencies are reporting that the remnants of Tuesday's trio of huge CME's should arrive this Friday the 13th with decent potential to disrupt GPS so.. be cautious!
http://news.sky.com/story/1280838/solar-flare-could-hit-earth-on-friday-13th
http://news.sky.com/story/1280838/solar-flare-could-hit-earth-on-friday-13th