Snowpack Update - April, 2025
You’ve probably heard that old phrase, “If you don’t like the weather in Montana, just wait 5 minutes and it will change.”
Well, spring time in the mountains takes that old phrase and cranks it up to 11. Sun & clouds, calm & windy, cold & hot, snow & hail & rain & other forms of precipitation that challenge the mind to define without using foul language. And all of that before lunch! What does that mean for the snowpack graphs? Just about anything can happen. Additionally, this is an interesting time of year for our local watersheds as we are at or very near the traditional dates of the “Median Peak SWE”, which in lay terms means “the date when we usually have the most water stored in the snowpack for the year”. We could just as easily see the beginnings of runoff or another 2 feet of snow!
Since our last report (March 17) all of our local watersheds except the upper Henry’s Fork have seen a net increase in snowpack.
The Madison – gained about 3 inches of water and then lost about 0.7 inches over the past week
The Gallatin – gained about 3.7 inches of water and quickly lost about 1.5 inches over the last couple of days
The Yellowstone – gained about 1.7 inches of water and then recently lost about 0.5 inches
The Upper Henry’s Fork – gained 2.2 inches of water and then subsequently lost it for a net 0 gain.
That said, the net gains have not resulted in increases to the daily numbers relative to median. The Madison has dropped from 97% to 95%. The Gallatin has dropped from 105% to 99%. The upper Yellowstone has dropped from 99% to 96%. And the Henry’s Fork/Teton has dropped from 98% to 88%.
I mentioned earlier that we are we are at or very near the traditional dates of the “Median Peak SWE” for our local watersheds. Let’s take a closer look, fellow nerds. Traditional dates for the Median Peak SWE are as follows.
Madison – April 22. While the graphs are showing that we have peaked already, the upcoming storm cycle could easily bump us back up and on track.
Gallatin & Upper Yellowstone – April 24. The Gallatin may have seen an early peak this year unless we get a big blast in the upcoming storm cycle. The Yellowstone headwaters are trending normally.
Upper Henry’s Fork – April 10. This year the peak appears to have occurred on April 9, unless we manage to pick up another 2,5 inches of water in the upcoming storm.
All of these trends are clear on the individual watershed plots. Perhaps another interesting point to consider is that all of these watersheds save the Henry’s Fork are doing much better this year than they were in 2024 (the orange line) but a fair bit lower than in 2023 (the purple line). The Upper Henry’s fork looks to be tracking similar to last year.
The weather report for the rest of the week is grim if you are looking to work on your tan, but awesome if you are looking to build some snowpack!
Our friends at the Gallatin National Forest Avalanche Center (GNFAC) are always ready with the great snow and weather intel. From their 4/16 report, “By Friday morning 1-2 feet are possible in the mountains near Bozeman and Cooke City with at least 8-12” in most areas.” This means we could easily see another 1 to 2 inches of snow water equivalent added to our local watersheds by the weekend!! If you have any interest in snow science, avalanche conditions, or mountain weather, you owe it to yourself to subscribe to their daily emails and regularly visit them on the web at www.mtavalanche.com/
That was a lot, but sometimes a lot is good. We will be back again in May with our final snowpack report of the year, just in time for the start of FISHING REPORT SEASON!!!
Take Care,
Matt and the BSA Crew
