As part of a High Sierra Trail backpacking trip, I hiked the Mt. Whitney Main Trail (MWMT) on June 22. Here are some thoughts temperatures we encountered, trail conditions, and gear.
On this trip I carried a Delorme InReach from LowerGear.com. Among other things, this device allowed us to get weather forecast as an automated reply as a text message from friends/family. We had planned on spending the night on the summit or at Trail Crest. The forecast (temperature and wind chill factor) put the overnight temperatures in the mid to high 20s, so we opted to stay near Guitar Lake.
In talking with other hikers and a ranger, we found that it has been very windy from Trail Crest to the summit. If I had to guess, I’d say the windchill put the temperature into the 20s around sunrise on the 22nd. We ran into a few hikers that weren’t prepared for the cold temps above Trail Crest and that were surprised how cold it was based on the temperatures in Lone Pine and on the lower sections of the trail
Below the switchbacks, the trail was very hot. The CDEC station at Cottonwood Lakes (located at 10,150′ and about 6 miles away from the MWMT as the crow flies), recorded June 22nd’s high temperature at 72°.
From Trail Crest to the summit, there were a few patches of snow and ice (pics below). Most of these can be avoided.
From Trail Crest down to Trail Camp, much of the trail is covered with water. We started our descent from Trail Crest around 9 am and it appeared that anything above 13k was freezing overnight. There was even some ice near around the spring at switchback 22.
We did not carry any traction devices, but hiking poles were very useful. I could see having some problems with ice on the switchbacks if ascending early, but none of the hikers we encountered were using microspikes or similar devices. If you take your time and are careful about foot placement through the icy sections, normal footwear should be sufficient.
It may be hot in Lone Pine, but warm layers are still needed, especially from Trail Crest to the summit.