Yesterday some of the NSIDC data for Arctic Sea Ice Extent and Antarctic Sea Ice Extent was missing, resulting in some strange graphs.
Today things appear back to normal except the data for Nov 11 is missing completely. The data is usually updated at 7:50am every day. Todays data is missing.
The current data is dated 3:46:00 PM Nov 11, 2013 (yesterday).
sunshine hours 
Do they or anyone else give an explanation for this?
Commenter Glacier noticed this on the NSIDC site:
“November 6, 2013: Data updates are currently intermittent due to technical difficulties with the data provider.”
Yea, I saw that and posted it here:
https://sunshinehours.wordpress.com/2013/11/06/arctic-sea-ice-extent-update-nov-6-2013/#comments