A spring low pressure system moved across the Central Rockies and into the high plains on Tuesday April 24, resulting in two rounds of snow showers across the Front Range of Colorado. This activity followed the first appreciable round of thunderstorm activity of the season across the Denver Metro area on Monday evening. The first round of snow arrived early Thursday morning, as a band of snow moved across the I-25 corridor between about 4:30am-6:30am Thursday. Snowfall amounts with this system were generally under an inch for most of the Denver-Boulder metro area, though up to 2″ fell around Golden and in the Boulder and Jefferson foothills.
On Tuesday afternoon, a more widespread round of snow shower activity developed across the region, favoring the southern and western Denver suburbs. These snow showers were fueled by a combination of favorable upslope flow and an upper level jet streak (i.e. a local wind maximum in the jet stream). While much of the Denver metro area received non-accumulating (or minimally accumulating) snow Tuesday afternoon, higher elevation suburbs and foothills areas saw respectable amounts. Up to 3″ of snow fell in Douglas County around Castle Rock, as well as in the Golden area near the foothills. For the Front Range foothills, heavier snowfall of 5-8″ fell around Nederland while the Jefferson foothills picked up a general 2-4″ of snow.
For the rest of this week, the pattern will be less active across Colorado. By this weekend, temperatures will be getting well into the 70s across the lower elevations, but the pattern will also begin to turn more unsettled over the weekend and through much of next week. A slow-moving trough of low pressure will move into the Great Basin on Saturday, and despite the warm temperatures enough moisture will stream into Colorado to result in convective activity, i.e. isolated thunderstorms across the mountains and possibly out on the plains as well from Saturday through Monday.
For the middle of next week, the trough of low pressure should move across the Central Rockies and into the plains, and although the impacts are highly uncertain and storm-track dependent this far out, the pattern will likely be active during this time with the potential for respectable moisture across Colorado. It may continue to be more of the convective shower/thunderstorm variety, but we may see a more widespread precipitation with colder temperatures fill in at some point, which would include high elevation snow for portions of Colorado. It will be interesting to see how this plays out, but for now expect unsettled conditions next week. Below is an image of NOAA’s Climate Prediction Center which gives an outlook for above average precipitation in the 6-10 day timeframe.