Today's 1-minute chart. Note the big volume candles in the 1:00-2:00 hour. That would be lunch hour in the central time zone. So maybe some of the shorts took their lunch hour to sneak away from their post in the janitor's closet, to do a little trading.... 
http://bigcharts.marketwatch.com/quickchart/q...&show=
http://bigcharts.marketwatch.com/quickchart/q...&show=