Scheduling Considerations

The backpacking season for the Wind River High Route is short: three months, July through September, in an average year.

But the most optimal window is even shorter: August through mid-September, or mid-July through mid-September after a dry winter. By pushing it earlier or later, you are more likely to encounter heavy bug pressure, high-water hazards, and/or excessive snow; or you are at an increasing risk of being shut down by an early winter storm.

It’s late-July, yet I wish I had brought my skis. Lingering snowpack in Bear Basin (elev 11,200 feet) after a very wet winter and cold spring.

It’s late-July, yet I wish I had brought my skis. Lingering snowpack in Bear Basin (elev 11,200 feet) after a very wet winter and cold spring.

More specifics:

1. Winter snowpack.

Between about November and April, the Winds are pummeled by Pacific storms that drop hundreds of inches of snow, especially along the crest.

The snowpack normally begins to melt out in early-April, starting with the lowest elevations. Peak melt occurs in June. And most passes are snow-free in or by August. After a drier-than-normal or wetter-than-normal winter, this timeline can be accelerated or delayed by about a month. Some snow never melts, which contributes to the many glaciers and permanent snowfields in the Winds.

Lingering snowfields can be a blessing, especially if it covers nasty talus or loose scree. But extensive snow coverage makes for more challenging conditions. Expect chronically wet feet, afternoon slogs on mushy snow, and some additional risks, including cornices that can block passage and icy morning crusts that increase the chance of a fall.

While the High Route can be shut down for a few days by a freak summer snowstorm, it will most definitely melt out due to the relatively warm air and ground temperatures, and the intense solar radiation. In a typical year, snow begins to permanently stick in October, especially on north-facing aspects and at higher elevations.

A developing thunderstorm in the upper North Fork. At 10,500 feet, this low-elevation alternate is safer than the ridge, but it still offers little protection.

A developing thunderstorm in the upper North Fork. At 10,500 feet, this low-elevation alternate is safer than the ridge, but it still offers little protection.

2. Summer monsoon.

The prevailing summertime weather system in the Winds is the North American Monsoon, which normally picks up in early July and fades in September. This pattern also affects Colorado, Utah, Nevada, California, and especially Arizona and New Mexico.

Intense solar heating of the southwest US allows moisture from the Gulf of California, the eastern Pacific, and the Gulf of Mexico to flow into the region. This moisture first manifests in puffy, cottonball-like cumulus clouds that build throughout the day, peaking in size and quantity in late-afternoon before dissipating in the evening hours. Cloud development is often greatest over high land masses, which forces the moisture upwards into colder air.

On days with early build-up of cumulus clouds, afternoon thunderstorms are more likely, and sometimes inevitable. Lookout for a dropping cloud ceiling and dark, vertical cumulonimbus clouds with an anvil cap.

Monsoon thunderstorms are often violent and dangerous. A lightning strike is the risk with the highest consequence, but the odds are relatively low. The more assured risk is exposure, which can lead to hypothermia. The thunderstorms drop torrential rain, and sometimes hail or sleet. And the ambient temperature drops suddenly and significantly, since the dry Wyoming air has little thermal mass to counterbalance strong downdrafts of cold air from thousands of feet above.

In addition to lightning and cold-and-wet conditions, thunderstorms can also cause a loss of visability as low clouds engulf the mountains.

The Wind River High Route is often in high and exposed terrain, the last place you want to be during a thunderstorm. Additionally, off-trail navigation is very challenging and possibly dangerous when visability is limited, even if you have a GPS: it may tell you exactly where you are and where you need to go, but it cannot identify an optimal or safe route to get there.

In July and August, expect afternoon thunderstorms at a minimum, and less predictable thunderstorms during very active monsoon patterns. Summer weather is much more similar to Colorado and Utah than to California. Utilize fully the morning weather window, and be aware of lower alternate routes if you are forced down.

Biting flies leave their mark on Buzz Burrell’s legs, so long as they find their way through the fur. The bug pressure peaks in July and fades into August.

Biting flies leave their mark on Buzz Burrell’s legs, so long as they find their way through the fur. The bug pressure peaks in July and fades into August.

3. Bugs

The mosquitoes and biting flies normally reach their peak in July, once the snowpack melts out, the vegetation greens up, and the temperatures warm. The most intense pockets are found in soggy areas when there is little wind. Bug pressure fades through August and ceases completely in September.

The bugs in the Winds are not on par with those in Alaska, but they are as bad as anywhere in the continental US. Bug-resistant clothing (e.g. long-sleeve shirt and full-length pants, treated with permethrin and/or made of tightly woven fabrics) and a headnet is highly recommended. A bugproof shelter is useful, too, although the bugs usually go away at night so long as temperatures are below about 50 degrees.

4. River fords

As a crest route, the Wind River High Route crosses most creeks high in their watersheds, before they can accumulate to dangerous volume and velocity. The section-hikes generally have higher water hazards, so beware especially during the peak melt in June.

There are four potentially problematic river crossings on the High Route: the Middle Fork of Bull Lake Creek, the two upper forks of the North Fork of Bull Lake Creek, and Dinwoody Creek. Fortunately, in all cases there are safe fording locations nearby, where the creek slows down and/or widens out.

11 Comments

  1. Ian on May 20, 2017 at 4:19 pm

    Hey Andrew,

    I’ve been planning out a traverse of the Winds for a while now, and was hoping to go through with it this summer. I’d be starting in the far south and would head north, to Dubois, basin-hopping for 400 miles or so. The month of July is my only window. Given the ridiculous winter we just had, the higher country will definitely still be buried in snow. When do you think the high bench, 9000 to 11000 feet or so, will melt out and green up, given we have a significant warming period over the next month and a half? I don’t mind traversing sketchy snowfields higher up in the range as long as its green where it should be green. At this point it’s beginning to seem like I’ll have to push it back for a third year…

    Thanks!
    Ian

    • Andrew Skurka on May 20, 2017 at 4:24 pm

      I did a trip in late-July in 2011 (after an equally big winter) and was shocked at how much snow was still lingering on the west side of the Divide between the upper headwaters of the Roaring Fork and Pixley Creek. It was still ski season up there.

      This year, I think August is going to look like a normal July.

  2. Ian on May 20, 2017 at 4:42 pm

    As I feared, with snow pack mostly above 300% after the latest storm. Unless climate change pulls through,
    (A horrible miracle?) it’ll have to wait another year. To the North Cascades it is, then!
    Thanks for the quick reply!

  3. Jacob Kosker on May 20, 2018 at 7:20 pm

    Well it’s a year later. How are things looking for this year? I’m finally considering getting out there and it looks like as of right now the snowpack is 110 to 125% the median. Is this promising for an early August trip or does it look like a delayed Jjuly” type of conditions again (snow fields, runoff, and mosquito clouds)?

    • Andrew Skurka on May 21, 2018 at 9:01 am

      June: bring your skis
      July: the month of transition, with more snow but few bugs early in the month, and less snow but more bugs later in the month
      August: normal conditions, with snow lingering where it piles up the most, and bugs into the middle of the month

  4. Jeff on July 20, 2018 at 1:02 pm

    Anyone done in it the last few days? I’m starting 7/24/18 and wonder what the snow situation is.

    Also, what’s the best strategy for weathering a thunderstorm in an area with no forest to hide in? Get close to the base of a peak?

    Thanks!

    • Andrew Skurka on July 27, 2018 at 9:10 am

      At this time of year after a wet winter, I’d expect snow to still be lingering where it tends to linger, i.e. leeward aspects at high elevations.

      Re thunderstorms:
      1. Start very early in the day. Thunderstorms are usually an afternoon event.
      2. Use alternates to get low or to bypass high sections.
      3. Wait out storms from safe places, then jump on favorable windows.

      • Jeff on September 11, 2018 at 4:19 pm

        Thunderstorms: more on this…

        The three tips you gave are certainly good advice; thanks much for those.

        But what about the case where one sneaks up on you? Maybe your view of the sky is obstructed by nearby peaks, or a storm is embedded in regular (non-storm) clouds… what then? There’s no forest. How do you minimize risk in this situation?

        • Andrew Skurka on September 12, 2018 at 11:18 am

          I really don’t like “what if’s.” They tend not to be grounded in reality.

          I’ve never had one sneak up on me. They don’t move that fast, and usually the sky gives you plenty of warning that it’s about to explode, even far from the epicenter of the storm.

          That said, I definitely have seen clouds that made me nervous, partly because I couldn’t see the entire storm cell. So you play it by ear, and take the risks that you’re willing to take, e.g. deciding whether to go over the pass now, or wait “it” out (even though it may be nothing) and minimize your risks.

  5. Ken on July 23, 2019 at 2:00 pm

    With the late winter the Winds have experienced, is there any intel known to say if the high route is even safely traversable this year? Purchased the map set and Wind River guide a few months back, plan to begin attempt Aug. 4th with a group of 5 others if thought to be doable. Very stoked about the trip, but if the high route isn’t traversable, which of your alternate routes is your favorite backup?

Leave a Comment