Looks closely and see about 6 miles away is Didcot Power station, likely to receive a direct hit if a full scale nuclear exchange where ever to take place. I'm standing atop the Chilterns at Nuffield. At this distance I would be largely safe if I shielded myself from the initial few seconds of intense light, say behind a car. I would certainly feel the shock wave which would hit about 20+ seconds later travelling at the speed of sound, but could stand against it if I braced myself. If the burst were made to hit the ground, which would create a lot of fallout and be an unusual military tactic, I'm at 90 degrees to the typically prevailing wind direction which would take the danger toward the right in this photo. If the wind were travelling in my direction, I'd either need to vacate the area quickly and in the fastest way (calculate the best direction to drive fastest from the cloud, much like the Enola Gay, but for her just to escape the blast, probably about 8 o'clock ...
North Stoke Life
Sightings from North Stoke, Oxfordshire, England