The above image was just taken from the Terminal Doppler Weather Radar (TDWR) in southeast Tulsa. It is a rapid scan, very high resolution radar without all of the ground clutter that we normally see in and around a major metropolitan area.
As you can see, 3 storms are trying to form: just South of Okmulgee, between Broken Arrow and Catoosa, and just South of Chelsea. These developing storms are moving Northeast to East/Northeast at 20 mph.
The storm South of Okmulgee has shown persistent growth over the last 15-20 minutes, and could explode into a severe storm at any time. Very large hail, damaging winds and tornadoes are possible with any severe storms that do form this evening.
The orientation of this developing activity ahead of a surface boundary moving through Tulsa at this time tends to suggest that the threat of severe weather development has shifted to the East of the City of Tulsa proper at this time. The boundary itself is still over the city, but all development seems to be taking place some 10-15 miles East of the boundary.