I am still amazed to see how quickly the weather can change on Mount Washington and how quickly things can go wrong for the unprepared.
It doesn’t sound like your friend was amongst this group. I’m sorry that you lost someone tragically there.
I hiked the Presidential traverse, including summitting Mt Washington, in a string of cool, dry, bright sunny days one July. You could not have asked for better conditions. It was still challenging and dangerous. That mountain is a killer. I saw the board listing all the fatalities in the observatory at the summit.
Drove up it once. Yuck. Scared crapless. Was 73 at the base, 13 degrees on top. Talk about windy.