When does high country typically melt out?

[Lisina10]

Howdy. I usually make my trips down from OR in late Aug or September, but this year I have more availability btwn mid June and mid July. Wondering if that would be too early to get into the higher elevations (I'm thinking northern Yosemite/Hoover Wilderness area) due to snow or death by mosquitoes? Thanks!

[GGC23]

The answer to your question is highly dependent on the amount of snowfall that the Sierra received during the winter. In just the past three years, we've seen an extremely wet winter in 2018/19 where I was postholing up to my waist until late July, a semi-dry winter in 2019/20 where there was some snow lingering on the north sides of passes in mid-June but almost everything was melted by early July, and a super dry winter this year where it looks like the snow is going to be gone by Memorial Day. So based on this year's snowfall, I think you'll be fine in the timeframe you've proposed. In fact, I think that August and September are going to horrible and filled with wildfire smoke this year, so your decision to move things up to the June/July timeframe is smart.

Bugs should also be lighter this year. Less water = less bug breeding ground. But that's harder to predict than snow because something as tiny as walking 100 yards away from water can often be the difference between "death by mosquito" and "this is bearable." That said, northern Yosemite is notoriously terrible for mosquitoes.

[kpeter]

In one of those mythical "normal" years you can often get a trip in before mosquito season in very early June if you can figure out the right destination--lower elevation, no stream crossings, etc. From mid June through the first two weeks of July there are usually mosquitoes in force at just about any elevation you can get to. The prime backpacking period is usually the last week of July through the first two weeks of August, since until mosquitoes are reduced, stream crossings and snow in passes cease to be a problem, and the fires are typically not burning yet etc.

That said, in very dry years you can move the clock back several weeks and move up fire season. In very wet years you can delay everything by several weeks. And to further complicate matters the warmth of May makes a big big difference. A dry winter with a very cool May can wind up being similar to a wet year with a hot May--because of the different speed of melt-out.

This year I am beginning my big trip on July 19, and will try for several play-it-by-ear trips beginning in late May, and will monitor this board closely to see how things progress.

[c9h13no3]

Howdy. I usually make my trips down from OR in late Aug or September, but this year I have more availability btwn mid June and mid July. Wondering if that would be too early to get into the higher elevations (I'm thinking northern Yosemite/Hoover Wilderness area) due to snow or death by mosquitoes? Thanks!

It depends so much on the weather. And mosquitoes and snow melt are two different things. Snow can be melted & gone, but if temps at night are below freezing, it will keep the mosquitoes at bay. Last year, the mosquitoes didn't get bad until the final week in June. But it seemed like that was a bit later than usual.

In a year like this one, I'd guess you'd be good for a trip in early or mid-June. The Hoover area has a decently healthy snowpack this year, but it'll still be mostly gone by June. Further south & higher in elevation, you are more likely to get the cold temps that reduce mosquitoes with less snow though.

[Wandering Daisy]

With the way the snow is melting, I doubt snow will be your problem. However, Northern Yosemite and Hoover Wilderness are notorious for mosquitoes. Seems like every 4th July I have been in either location, swarms of mosquitoes. What can save you is wind. One year I avoided mosquitoes by staying up on windy ridges, such as Koip Crest- stay out of deep soggy valleys; Lyell Creek below Donahue Pass is horrible.

This year there is the added difficulty of getting a permit. Southern Sierra has been very dry this winter, and has less mosquitoes in any year, but east side trailhead permits are getting scarce. I just picked up a July 12 permit for McGee Creek, there were some left. You may be able to get one of the 2-week prior "walk-in" permits. Since you were asking about Hoover Wilderness, you are already willing to go to the east side, and it really is not that much of a drive to get down to the Mammoth or Bishop areas.

Good Luck!

[texan]

WD is right about the skeeters, I wouldn't go to Hoover, Emigrant, or Northern Yosemite until August 1 even in dry year. Have a good trip and good luck!

Texan

[Wandering Daisy]

http://cdec.water.ca.gov/reportapp/java ... =DLYSNOWDP

This is updated daily so you can follow/compare the snowmelt at various locations. Each location has a code name. You can look up exact locations. You may have to go back a page or two to find this link. The menu on the top will take you back to the snow page where there is more choices of information.

[wildhiker]

WD is right about the skeeters, I wouldn't go to Hoover, Emigrant, or Northern Yosemite until August 1 even in dry year. Have a good trip and good luck!

Texan

That's a rather extreme view! Here are some June and July trips I did in Emigrant and Hoover Wilderness areas in previous years with no mosquito problems:

July 4th weekend, 1977 - out and back in Emigrant Wilderness from Bell Meadow to Chain Lakes and Hyatt Lake.

July 1, 2006 - day hike up Molybdenite Creek in Hoover Wilderness.

July 4th weekend, 2007 - loop in Emigrant Wilderness from Crabtree Camp to Groundhog Meadow, Rosasco Lake, Pinagree Lake, Kole Lake, Wood lake, and back via the higher trail past Gem and Piute Lakes.

June 21-22, 2012 - out and back in Hoover Wilderness from Green Creek trailhead to Hoover Lakes (granted, this trip was very windy, so that could explain no mosquitoes).

July 23-24, 2020 - out and back in Hoover Wilderness from Green Creek trailhead to Green and West lakes.

-Phil

[kpeter]

WD is right about the skeeters, I wouldn't go to Hoover, Emigrant, or Northern Yosemite until August 1 even in dry year. Have a good trip and good luck!

Texan

My experience in Emigrant and Northern Yosemite is that it is often possible to get a trip in before mosquito season. Late May and the first week of June has been kind to me that way, and a couple of trips have been OK in the 2nd week of June. I have had terrible mosquitoes on other trips in the 3rd week of June, and have never even tried later than that.

Mosquitoes become very bad about two weeks after snowmelt, so the trick is to get in--and getting to the right elevation--during the first week after snowmelt. What often happens in mid June is that you will run into terrible localized mosquito bands at particular elevations, but they have not yet had time to move around and become ubiquitous everywhere, and you can find pleasant places to camp. By late June it is hopeless anywhere, any year, in those lower elevation wildernesses.

[balzaccom]

We've also "changed" elevations to miss the skeeters. One trip around 4th of July, we climbed up above the main cloud of mosquitoes...

They were fierce at 7500 feet, but at 9,000 feet in partial snow, they were much easier to deal with.