Does anyone know the impact that this year's heavy snowfall will have on hiking the John Muir trail in July or August? I've been told that the biggest concern would be stream crossings, which could be more difficult because of more snow melt. I'm trying to get a better sense of the conditions before committing to a trip scheduled for the first couple weeks of August. Thanks

TSTT (too soon to tell) what things will be like in July...

But I'm thinking by August that the high runoff will have abated quite a lot. And the crossings on the JMT that are of concern later in summer have bridges over them.

Yup, later will be safer than early and there's simply no way to know. Snowpacks are over 200% of average in some basins.

A hot summer will clear most out; a mild summer means a lot of snow will linger until next winter. I'll guess the north slopes of the higher JMT passes will have snow through the season, but they'll get heavy travel too.

I feel sorry for NOBO PCT thruhikers!

Cheers,

For sure the heavy Sierra snows will affect NOBOs on the PCT this year, but think of the fiendish bragging rights they'll acquire if they make it all the way to Manning in such a tough year.

We are doing the JMT July-August. Our very experienced friend (has completed the JMT 7x) who we're going with told us that we should be prepared for cold nights (insulated jacket is a good idea), mild days, snow on passes (but won't need crampons because the PCTers will be trudging through it 2-3 weeks before us), and high water stream crossings. Main thing being cold nights!

In mid to late June the NOBOers doing thru-hikes this year will be postholing a much larger percentage of the day's mileage than would be true in more 'normal' years. That will be a physical challenge. Sadly for them, this mega-snow situation is not confined to the Sierras. All the western mountains seem to have well-above-average snows.

btw, have a great time on the JMT!

Thank you all for your advice and suggestions. I'll try to post any weather updates if I find them.

Although this heavy snow year presents a challenge, one has to keep in mind that it presents an opportunity as well. It will be up to each person to determine what that is for themselves. In the 60's, 70's, and even 80's there was typically much more snow in the passes at the end of August than a typical year now. I will grant you that it was much more compacted in general. As for me, my end of July off trail trip above Sierra Nevada treeline is on; I'm just probably bringing gear I haven't brought in a while. Give yourself extra time to negotiate hazards safely; have backup campsites just in case. It's all stuff you already know.

Early indications are that the snow water content is close to that of 1993. A lot more than last year, which was a pretty tough year.
One thing's for sure, the mosquitoes are probably going to be around until September, from the looks of things. LOL!!

Early to mid-July will be affected- higher water. Because of this I think permits will be hard to get in August and Sept because everyone will be delaying or cancelling early plans. I bet there will be permits available, even on a first-come basis in June and early July. The temperatures the next two months will have more to do with conditions than the depth of snowpack right now. Snow is predicted all this week above 8,000 feet!

For those going in late July or early August, there will be bugs. Late snow melt off will provide for a lot of mosquitos. I have been out the first week of August after a heavy snow year and had to wear the bug net all day long while hiking. There won't be any problems with dried of streams. This would be a great year for a late August, early September JMT trip.

I start my trip at Tuolumne Meadows on August 15. Hopefully, the bugs will have died out by then, but I doubt it.

Do you think river/stream crossings will prove particularly challenging because of the heavy snow melt?

I did the JMT in late July/early August 2006. That was a wet year but not nearly as wet as this year. All the high passes had snow but it wasn't really a big problem. Muir Pass was probably the worst. There was enough snow to do a standing glissade down part of the north side. Many folks were carrying axes and 'pons but they were not needed.

The real issue, as mentioned above, was the stream crossings. They were deep, cold and frequent. Some were a little dangerous. I went S-N and my feet were wet all day every day until Donohue Pass. There were just too many crossings to take my shoes off every time so I just lived with wet feet. On several mornings I had to put on wet shoes when I started for the day. The good news was, I never had to carry more than a quart of water at a time.

And yes, the mossies were out in force. I always has a litlle extra protein in my oatmeal