A winter-like wind is howling outside the office windows as I write this. It's amazing how fast the weather has changed here. It was 103 less than a week ago here in Las Vegas.
I hope your sons and nephews elect to postpone such a trip. Whitney is not a fun place in a blizzard.
The web cam from Sentinel Dome is already showing heavy snow on top.
(Photo: Yosemite Conservancy Org.) Half Dome is usually visible in this image!
The park will want to keep the road open as long as they can... and it could still turn hot/warm next week.
Mark