I was going to start this forecast by saying “in typical Colorado weather fashion” but to be honest, Colorado’s weather has been anything but typical lately. What Colorado’s weather has been lately is just dry, warm and windy. An incoming storm could change that by Friday.
This week has featured a chance of afternoon storms almost daily across the state. A summer-time pattern that has finally revealed itself after one of the driest Aprils on record. Though not everyone will be seeing the afternoon pop-up thunderstorms, those that do should consider themselves lucky for the reduced fire danger that comes with it.
We’ll take any and all moisture we can get before Thursday because another day of heightened fire danger is expected across the state as our approaching storm nears.
One of the big reasons we’ve had so much wind lately is because the storm track has been to our north bringing Montana and the Dakotas wet and cool spring weather. The position of low pressure systems to our north leaves Colorado in the dry and windy sector of storms. The incoming storm on Friday will still push a little too far north to impact us hugely but it will be close enough to deliver some cold air and precipitation.
Thursday – Fire Danger
First, it will bring high heat, high winds and dry air and all of that combined will create heightened fire danger yet again. Thursday will come with temperatures running 20-25 degrees above normal. That lands most of the eastern Plains, including Denver, in the 85-95 degree range with a few locales in southeastern Colorado nearing 100 degrees. Winds will be sustained around 10-20 mph with gusts up to 30-40 mph. Relative humidity values will drop below 15 percent, especially in southern Colorado which is where the worst fire danger is likely to be on Thursday.
Thursday Night to Friday – Cold Front and Rain
Then a potent cold front will roll through Thursday evening. This cold front will drop temperatures a good 40-50 degrees by Friday morning across the Denver metro. In a classic upslope event, cloud cover and precipitation will form by Friday morning but become widespread by the afternoon. Highs on Friday across the metro will struggle to break out of the 40s. A stark difference from the near 90 degree heat we will have felt on Thursday.
Actual Snow Chances
This will be a cold storm and temperatures will be cold enough to support some snowflakes but the majority of the time, Denver will just be experiencing just a cold rain. It’s been oddly warm lately, the sun angle is way high this time of the year, ground temperatures are warm and this storm is just not as strong or as close as we would want it to be for Denver to see accumulating snow. However, those above 6,500-7,000 feet in the Foothills west of Denver have the greatest chance of seeing a few slushy inches of snow. Similarly, areas along the Palmer Divide near Monument and Castle Rock could see a slushy inch or two of snow by Saturday. Rocky Mountain National Park and some of the high terrain in the Front Range mountains have a solid shot of seeing several inches of snow.
For Denver and the lower elevations, the best shot at some snowflakes for us comes Friday afternoon and evening as the coldest air really sinks in. Again, we’re not expecting anything major in regard to snow totals across Denver and really, that’s a good thing. With leaves on most of the trees, a major snowstorm this late in the season could have some horrible effects on vegetation so a cold rain is perfectly appropriate.
Freeze Potential Saturday AM
With that said, it will be cold Saturday morning. Temperatures are forecast to reach near-freezing Saturday morning which leaves higher elevations above 6,000 feet well into the 20s. You should prepare to protect any sensitive plants you may have sown already. This storm will be bringing some much needed moisture with it so many plants should be happy with the free water. It’s looking like near a half-inch of precipitation could fall across Denver and the surrounding areas from Friday to Saturday morning. Some of the higher elevations near the northern Foothills may see up to three-quarters of an inch of moisture from this storm.
In all, we’re not looking at a blockbuster late-season snowstorm in Denver but we are looking at a rather cold storm with decent moisture which is great news. Stay tuned for updates. If this storm comes in stronger and colder, we will be talking about more snow than rain but we will still have to overcome quite a few obstacles to get the forecast to pan out.