Have you ever wondered how long it takes all the snow in the Cascades to melt? Of course it depends on the elevation, with higher elevations (cooler temps) taking longer. Well today was the day the Mt. Hood Test Site saw the last of its snow melt. Actually the snow depth sensor finally went to zero yesterday, but the “snow pillow” that measures snow water equivalent is still seeing a little. I’m not a sensor expert, but decided today was close enough.
I’ve had some spare time at work the past few days, so I wanted to see if the date at that location is earlier or later than in the past. You might be surprised at what it shows! Data at that location at 5,400′ goes back to 1981.
You can see the earliest was the drought year 1992 when the snow disappeared by May 25th. The latest was just three years ago in 2011, when the last of the snow disappeared the 2nd week of August. Now the data period is quite short; only about 30 years, so don’t try to draw any earth-shattering conclusions, but the trend is definitely for a slightly later melt-out in the past 9 years.
I think it’s fair to make these two statements as well:
1. At the 5,400′ elevation on Mt. Hood, the snow is not melting any earlier than in previous decades. If anything it is sticking around longer.
2. The Cascade snowpack AT THAT ELEVATION and IN THAT LOCATION is sure not disappearing!
When I get some more time I think it would be interesting to see if lower elevation locations are similar, such as 3-4,000′ spots.
Chief Meteorologist Mark Nelsen