Why did Wheat Ridge get twice as much snow as DIA this winter?

If you’re looking for snow in the Denver area, you’ll usually want to drive an hour or so west into the foothills and mountains.

This winter, though, perhaps only a 15-minute drive west may well have made all the difference.

There was a notably wide gap in snowfall totals from the west side of Denver to the east side this winter, with the east side of the city receiving only about half of the snowfall that the west side received. Consider, for example, Wheat Ridge’s approximately 100 inches of snowfall this winter, compared to the 48 inches of snow that Brighton received.

To be clear, most winters feature some sort of noticeable gradient between all sides of the metro area. But as evidenced in part by Boulder’s record-breaking snowfall season, this winter favored the east-facing foothills west of Denver in a perhaps slightly unusual way.

For example: Denver generally saw a slightly above-average season of snowfall (57.6 inches at Denver International Airport, and about 71 inches at the Stapleton Airport weather observation site).

This was a generally decent-sized winter (30year average Denver snowfall: about 50 inches) for the immediate Denver area, but it wasn’t off the charts for local standards.

But if you push ever-so-slightly west into the west side of Denver and into the first suburbs on the other side of the city line, such as Lakewood and Wheat Ridge, those seasonal snow totals jumped dramatically.

Wheat Ridge saw more than 100 inches this winter, while Lakewood saw almost 90 inches of seasonal snowfall.

Although there’s typically a gap between the east and west sides of

Denver, the fact that the west side of the metro area almost doubled the east side’s snowfall is a bit of a wider spread than usual.

“There weren’t a lot of big synoptic storms that were widespread (in producing more evenly distributed snowfall),” said Scott Entrekin, a meteorologist at the National Weather Service office in Boulder. “Most of the folks on the plains only had 20 to 30 inches of snow, which is a bit below normal out there. We did have some upslope-heavy storms.”

If you stretch out the geography a bit, the gap gets even wider: Colorado’s Eastern Plains saw only about 20 to 30 inches of snow this winter, below average in most cases. Meanwhile, the foothills west of Denver saw as much as 200 inches of snowfall, well above the climatological average there.

This was likely the result of a high number of snowstorms that primarily pushed in easterly winds, or ones that strongly favor the foothills and the west side of the Denver area. Because elevation begins its sharp climb just west of Denver, easterly winds are forced to climb with the terrain as well.

When air rises, it condenses into moisture.

Easterly winds in eastern Colorado often transport moisture from the Gulf of Mexico, and during the winter, there’s often enough cold air in place that it leads to snowstorms.

This winter, an exactly easterly wind orientation helped boost foothills snowfall totals a bit more than usual.

“I think a lot of that is due to the upslope (wind) component from east to west in Denver, and as you go up into the foothills,” Entrekin said.

“East Denver saw anywhere from 50 to 60-plus inches, and that gradient really tightens up west of

I-25. East-northeasterly winds at the surface can lead to that pretty tight gradient. It’s almost double as you get toward Boulder.”

Traditionally, the wider snowfall gap comes between the south side of the metro area and the rest of the city.

The Palmer Divide, the mountainous area between Denver and Colorado Springs that rises up to 7,000 feet in elevation, is typically one of the more significant areas of snowfall across the metro area. The Palmer Divide’s elevation difference and geography is why places such as Castle Rock (83.5 inches of snow this winter) and Sedalia (about 80 inches) often wind up with some of the higher seasonal totals over the course of a full winter.

The divide, however, usually relies on a bit more of a northerly component to the winds to bring in colder and more upslope-dominant winds that will rise more efficiently against the eastwest orientated range.

But this winter, those Palmer Divide areas actually saw slightly less snowfall than places such as Wheat Ridge and Lakewood, and Castle Rock got barely half of Boulder’s 152 inches of seasonal snowfall.

That’s far from unheard of, but it certainly is a bit unusual, and yet another indicator of the huge snow season that the foothills had.

That led to a big difference in snowfall totals over just a few miles across the Denver area this winter, including slightly below-average seasonal amounts for areas just north of the city.

“Sometimes if you get too much of these northerly winds, you’ll get downsloping and drying (north of Denver),” Entrekin said.