05.27.11
Upgrade to EF4; May Go Higher
The Norman National Weather Service has upgraded the Binger/El Reno/Piedmont/Guthrie tornado, the Chickasha/Blanchard/Newcastle tornado, and the Washington/Goldsby tornado to EF4. They say that the damage surveys are not done, though, so any of these could even be upgraded later to EF5.
The second of these three tornadoes was the one headed for northwest Norman, south Moore, and possibly downtown Oklahoma City if it had not occluded, and the third was the one headed for the National Weather Center and south Norman if it had not occluded.
Here is the public information statement from the National Weather Service with more info on these tornadoes: http://www.srh.noaa.gov/oun/?n=events-20110524-pns1