How鈥檚 the snow on Northwest mountains this year? Overall a little deeper than normal, but it depends where you look. A new collaboration between the 91探花 and the Northwest Avalanche Center lets you see how the current snow depth compares to past years for nine sites in Washington and two in Oregon.
The new is freely available on the Office of the Washington State Climatologist鈥檚 website. It replaces a tool made more than a decade ago that collected snow depth data from the NWAC website to create a simple graphic on the state climatologist鈥檚 website.
鈥淲hen that display wasn鈥檛 working, that鈥檚 the one where we would get emails from ski enthusiasts or other meteorologists or climatologists. To us that was a good sign that we should rebuild it,鈥� said Karin Bumbaco, a 91探花research scientist who is the assistant state climatologist.
The new version, built with support from Tableau, is interactive, displays more data and is more reliable. It lets users explore differences in mountain snow depth from one season to the next and create a graphic of the results.
鈥淭his is a tool that people in the weather community, like meteorologists and climatologists, as well as snow recreationalists, can use to communicate the current snow conditions and how they relate to average conditions and previous years,鈥� Bumbaco said.
A default view shows the current year compared to the past 30 years of data at a single location. Changing the settings can display measurements back as far as 1927 for the longest-running stations, on Mount Baker at Paradise on Mount Rainier. Measurements go back to 1974 for the two most recent stations, at Mount Hood Meadows and Timberline in Oregon.
The Northwest Avalanche Center monitors mountain snow depth for their forecasting operations as avalanches pose risk to roadways and people venturing onto the winter slopes. Data are entered 12 times a year, on the 1st and the 15th of each month, during the monitoring season from Nov. 15 to May 1.
The monitoring sites are part of the center鈥檚 mountain weather station network. Some sites are owned by the Washington state Department of Transportation, while others are partnerships between NWAC and the transportation department, ski areas or national parks. While other measures exist, they don鈥檛 have the same history of similar measurements.
鈥淲e use this tool to track how our snow depth is building across NWAC’s forecast region in a historical context,鈥� said Dennis D鈥橝mico, meteorologist and forecast director at the Northwest Avalanche Center, who worked on the project. 鈥淟ocal professionals and recreationists track this report all season long. This new tool will allow them to explore historical snow depth data in a modern visualization tool at winter recreation access points.鈥�
The new tool complements a previous 91探花data visualization looking at long-term weather trends. Official trends in mountain snowpack are measured in snow-water equivalent, or the amount of water when the snow is melted. Those trends vary throughout the state and generally show long-term declines of about 3%-10% per decade, Bumbaco said.
“Tableau Public is an ideal medium for this sort of civic, historical data,鈥� said Blair Hutchinson, product manager at Tableau. “The visual dashboards we created provide people with a great way to interact and make informed decisions regarding the聽snowpack聽on a seasonal scale.鈥�
The many people seeking outdoor recreation during the pandemic are lucky that as of early February, most of the 11 stations are now measuring slightly above-normal snow depth. This winter had been forecast to be an La Ni帽a year, which is often slightly cooler and wetter in the Northwest, Bumbaco said. It鈥檚 delivered on half that promise, with December-January conditions generally warmer and wetter than average.
The continues to predict conditions slightly cooler and wetter than normal, Bumbaco said, which means we鈥檙e likely to see a healthy snowpack.
The new visualization tool was supported by Tableau.
For more information, contact Bumbaco at kbumbaco@uw.edu or 206-543-3145 and D鈥橝mico at dennis.damico@nwac.us.