April's kinda iffy..... If it's anything like this year, you'll probably have to start training your sled dogs.
Pretty sure you can expect snow, snow and more snow. The trail won't be marked as you won't be able to see it. There are a lot of hikers on this and other sites that can do it in April, but most have been on it so much, have extreme weather experience and can find the trail and shortcuts blindfolded. If your into an adventure and have crampons, ice axe, map the right clothing, gear and have experience in varied weather conditions and route finding, then please take a look at Whitney and have some fun.

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