State of the Snowpack: 3/25/2021

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As we dive head-first into Spring – which officially started March 20th – we’ve unknowingly stumbled into one of the driest March’s I can remember. Most of the ground snow in town is gone, but the mountains seem to be holding on! The high mountains continue to stay cold above 11,000 feet, but there is a subtle melt-freeze cycle happening currently, that will eventually stabilize the snowpack. We’re still a way from that point, however, and spring in the Winds is shaping up like it does normally. Currently, the Winds are engulfed by a large storm that has been going for the last few days.

If we look at the range from a station-by-station standpoint, snow depth totals look below-average. Fortunately, that’s not the whole picture – from a basin-wide average, things are not too far from normal; the Upper Green River Basin currently sits at 92% of average. Historically, March, April and May are the wettest months for the Wind Rivers, and although March has been unseasonably dry and warm, we’re hoping for more snow accumulation in the coming months. As the upper-air La Nina trough loses power with the warming of the higher latitudes, we transition into a more reliable orographic weather pattern that favors high-mountain regions. This NOAA article on understanding the Artic Polar Vortex helps make sense of the La Nina winter weather patterns.

So fear not! Although conditions vary year to year, we can most likely expect an “average” (not sure what that means anymore) start to the summer backpacking season. This means lower elevation trailheads thawing out as early as mid-to-late June, and high country access by early July. Stay in touch with us through phone (307) 367-2440 or email info@greatoutdoorshop.com for the most up-to-date conditions regarding the Wind River Range. Now for some data and nitty gritty details.

Earlier in this report, when I mentioned snow depth totals and basin-wide average, I was referring to this website. The NCRS compiles raw data using weather stations placed strategically throughout the range. They then compile that data into tables and compare that data to past-year averages. This is how we get a more accurate picture of the state of the snow and how we make predictions. Obviously its still quite early to forecast specific dates for access, but we can still infer a few things. Another interesting NOAA article, the National Climate Report 2021, gives a great overview of Winter 2021 in the West. Poking through this article will give you an idea of precipitation amounts, average temperatures, etc. for the Inter-Mountain West and Northern Rockies.

Poking around on this interactive map, we can get a closer look on how snow depth totals vary across the range. In general (although this can vary given the right year) the east side of the divide and the southern end of the Winds receive lower amounts of accumulation. You’ll see that the northern end of the range receives higher amounts of accumulation, and part of that comes from its proximity to Jackson and the Gro Ventures. Storms coming from that direction tend to ride high in the lower-air jet stream (and stay high) which is conducive to large storms.

When we zoom out on the map, to a basin-wide view, snow depth totals start to look a little better. Part of the reason for this are faulty equipment at stations that show them to read “0”. In reality, there’s snow there, the weather equipment just isn’t picking anything up. The basin-wide average is interesting from a fishing standpoint, as those looking to fish the Green River in the Pinedale area benefit greatly (and can fish longer into the fall) when the basin-wide average is close-to or above 100%.

As I’ve mentioned in previous reports, I try to take a look at each of these interactive maps whenever I can, as the snow depth totals and basin-wide averages change rapidly. Especially if you plan to come and backpack the range earlier in the season, these maps will give you an idea of what to expect. From here, looking at Google Earth’s historical photos and honing in on geographical aspects helps greatly during the trip planning process. Mountain Forecast and NOAA are great for getting 3-day forecasts for a particular part of the range in which you’ll be recreating. Remember that a forecast out from 3-days is usually not to be trusted; it may give you an idea of what to expect, weather-wise, but the accuracy of that forecast is greatly reduced.

Again, if you have any other specific questions for us regarding a trip plan, or are curious to what the conditions are like currently, give us a call (307) 367-2440 or email us info@greatoutdoorshop.com. In the next week or so, we’ll be busy at work switching the shop from winter to summer. We’re starting to get new summer product on the shelf and look forward to serving you in the coming months!