Does it feel like your neck of the woods has already received mountains of snowfall this winter? Then you’ll probably appreciate this striking new visualization by Dartmouth geographer Garrett Nelson, which turns this winter’s year-to-date snowfall totals into literal mountains.
“I’m a geographer, so I’m always finding ways to make new maps in my spare time,” Nelson told Earther via email. “In this case, I was just checking the weather forecast and happened to browse onto NOAA’s snowfall data page. I had a few hours on Friday before some weekend travel plans, so I threw this visualization together really quickly.”
The visualization shows modest hills of snowfall becoming towering mountains and spreading across the country as winter storm after winter storm hits. It’s mesmerizing to watch, but it’s also a handy record of a winter that’s so far been marked by several extreme storm events and plenty of white stuff. It also—to some extent—tracks the actual topography of the country, no accident seeing as higher elevations tend to get more snow.
Nelson pointed out that you can use it to track the way storms spread across the country—often from west to east, but also as counterclockwise rotating ‘nor-easters’ hit the New England region. Two major early season snowstorms in the southeast stand out, as do the crazy December pileups in western New York and Pennsylvania, when the region got a record-smashing dose of lake effect snow.
Making the snowfall viz was fairly straightforward. As detailed in a blog post published on Jan. 13, Nelson first wrote some Python code to scrape daily raster maps depicting snowfall accumulation totals from the National Weather Service’s website. He then warped the data into an Albers projection, used a technique called hillshading to create the appearance of topography, and layered snowfall totals for each date in a seamless, looping animation.
The map garnered quite a bit of attention on social media this weekend, even inspiring Cornell cartographer Matt Strimas-Mackey to make a colorized version:
Nelson plans to continue updating the map as winter wears on. And if you’d like to compare the final results with last year’s accumulation totals, he’s now gone back and created a winter 2016-2017 map, too: