fmeier, on Mt Whitney, the best practice is to stay away from the mountain if thunderstorms are developing. The trail travels north from Trail Crest for about 2 km, gaining the last 500 meters to the summit. If you are on that section and a lightning storm builds, you have no protection!
Last summer, there were not many thunderstorms on Whitney. But other summers, there have been quite a few. They tend to occur mostly in August, but can occur any month. They also tend to build in the afternoon.
Check the weather forecasts and talk to hikers coming down, just before you start. If thunderstorms are likely, you can minimize your exposure if you get to the summit and back down at least below Trail Crest by noon.
The hut will be open, so don't need a tent above your camp site. But you should consider a rain parka if rain is in the forecast.
