Get ready, Colorado. It's gonna be a big one.

A major winter storm is set to impact Colorado from Monday night to Tuesday, with heavy snow, gusty winds, and bitterly cold temperatures. You may have been hearing the mumblings of an intense snowstorm, and the fact is—yes, it's going to snow. A lot. We are looking at a very impactful snow event for the Urban Corridor and the adjacent Foothills. 

Before I talk about details, I want to mention the concerns that we currently have in regard to this storm. 

TIMING:

The timing of the snow entering Denver could be a tad later than originally expected. Snow should start sometime after 4 p.m., but the heaviest of snow should hold off until after 8 p.m. for Denver. Areas around Boulder and Ft. Collins will see the snow start much earlier. In fact, Boulder and Ft. Collins could have snow accumulating on the ground by 8 p.m. Monday night. The heavy snow will continue along the Urban corridor throughout the entire overnight period. By the time we wake up on Tuesday morning, there should be several inches of snow on the ground just about everywhere, from Denver to Ft. Collins to Sterling. 

AMOUNT OF SNOW:

The amount of snow is going to be great north of I-70, but where the forecast gets tricky is south of I-70. There's good confidence that Denver will get at least 8 inches of snow from this storm, but head 30-50 miles south of Denver, areas like Colorado Springs and Castlerock may end up with under 6 inches of snow total. We have to watch where the exact track of the storm ends up because if the track moves further north, there's a chance the southern Denver suburbs may see low-end amounts and Downtown Denver may see 4-8" of snow rather than the forecast 8-18" of snow.

Regardless of amounts, the snow will be very impactful to Tuesday's commute. Travel is NOT advised on Tuesday. If you must travel, you need to be prepared. 

So, let's now talk details. 

Snow will begin later Monday evening for most of the Front Range; earlier for areas to the north. Snow will begin light but within a few hours, snowfall rates will intensify quickly. We could be looking at 1-2" per hour snowfall rates. Snow will be heavy through Tuesday morning and will linger into Tuesday afternoon before subsiding. Once the snow ends, there will be the potential for over a foot of snow to have fallen in the Denver Metro.

For areas near Boulder, it's looking like 14-18" of snow is more likely. That same amount could be seen near Ft. Collins as well. With the possibility of over a foot of snow accumulating, you better be ready for travel delays on the roads to last through Wednesday. If you must travel by car, be sure to have an emergency winter kit ready in case you get stuck in the snowstorm

If you're traveling by air, be prepared for delays and cancellations. There will likely be major delays at DIA because of this winter blast. Check with your airlines ahead of time and be prepared to spend a lot of time getting to the airport if your plans continue on.

There are some variables that could lead to there being more snow in and around Denver:

  1. This storm could come in stronger than original thinking. Note: The models have been trending slightly stronger over the last few runs.
  2. The storm could come in further south, leading to the southern cut off line moving further south of the city. That would likely ensure Denver with double-digit snow totals.
  3. This storm may move slower than current thinking. If it were to last longer, that would mean more snow.
  4. Finally, there could be a stronger upslope wind event on Tuesday that lasts longer into the day, which would also lead to higher snowfall totals. 

As you can see, there are several ways that Denver could get more snow than forecast. With that said, there's also the possibility of Denver ending up with the low-end amount. Even with the low-end amount, which is about 6", this will still be an impactful snow event. 

Road conditions will continue to be bad through Wednesday since there will be a lot of snow leftover, and cold temperatures accompanying that.  

Stay up to date with current weather hazards from Andy's Twitter and the NWS Boulder Twitter. Current travel conditions, road closures, and traction laws can be found on the Colorado DOT Twitter.