At its widest, the El Reno tornado measured in at 2.6 miles, which is likely the widest tornado in American history. At its peak, it recorded perhaps up to 295 mph wind gusts and has been classified an EF-5, the second in Oklahoma this year and the 8th since 1950.
Let's put that in perspective, Philly style. Imagine you grabbed a cheesesteak at Sonny's on Market Street and decided to walk west to Landmark Americana near Drexel for a beer. I know it seems a bit odd since you can drink and eat at both places but work with it. That distance is about 2.6 miles by foot, about a 9 minute journey on the El. Not that such a tornadic scenario could unfold in Philadelphia but the width of El Reno would essentially swipe through the whole of Center City and a chunk of University City as well.
Taking the stroll to Broad Street -- if a tornado were to touch down at Broad and Pattison and march north up Broad Street...it would be a journey of 11 plus miles to go from Broad and Pattison to Broad and Cheltenham Avenue -- the El Reno twister would add another five miles to that (think going up into Willow Grove). Its path of 16.2 miles and duration of 40 minutes on the ground were not remarkable in their own light -- but the 2.6 mile width is something that is otherworldly.
The above image shows various doppler imagery of the El Reno tornado near its peak. The storm shows a couple of vortices revolving around the parent center. The fastest of these sported over 100 mph winds according to Greg Forbes at The Weather Channel. If you added that to the parent twister's 185 mph winds, you have a potential max wind gust of 285 or higher.
El Reno is definitely an unprecedented tornado, one that will likely remain part of the weather community's conversation for quite some time to come.