A very powerful storm system will move into Eastern Colorado on Wednesday, bringing heavy snow and very strong winds across the northeast plains. Blizzard warnings have been posted along the I-25 corridor from Denver to Colorado Springs and east to the Kansas border. Winter Storm Warnings are in effect for the remainder of the Front Range.
Check out the map below, which shows NWS Watches and Warnings across the Southern Rockies and Southern Plains (image source: pivotalweather.com). Not all areas will get snow, but most areas will experience very strong winds!
The sea level pressure with this system is projected to be near record levels for Colorado on Wednesday. The next image shows the forecasted surface low strength and position for Wednesday afternoon, with a projected sea level pressure of 974 millibars (image source: College of DuPage).
Sea level pressure values this low typically only happen with coastal systems, such as hurricanes/tropical storms or nor’easters, and are very rare in continental areas. In other words, this storm is going to be extremely powerful, especially with regards to wind!
This is going to be a high impact storm for all of Eastern Colorado in terms of wind, and hence the Blizzard Warnings. Snowfall amounts are tricky across the I-25 corridor, but even just a couple of inches of snow with wind gusts in excess of 50-60mph will cause major problems. And it’s likely many areas will see snowfall in excess of 6″. Travel is not recommended across Eastern Colorado Wednesday afternoon and evening.
Timing-wise, precipitation will start as rain late tonight outside of the mountains, with a change-over to snow across the Denver urban corridor by mid to late morning Wednesday. Snow will then fall heavily at times through Wednesday afternoon and into the evening, before tapering off overnight. This is a fast-moving system, but given the strength we expect snow rates to be heavy and could add up quickly over a short period of time. Combined with the wind, significant travel impacts are expected.
In our morning forecast, Skyview Weather predicted 4-8″ of snow across Metro Denver with higher amounts south and east of the city, and lower amounts west and north of the city (due to downsloping northerly winds west of I-25). These amounts may or may not need to be adjusted depending on model trends.
Keep in mind that with an anomalously strong system such as this one, models may not be accurately projecting the impacts, and it’s possible that snowfall amounts could be higher than what is currently forecast for parts of the metro area. We saw a similar scenario in March of 2016 when 2 feet of snow fell across parts of Denver metro in a relatively short period of time, and was higher than most forecasts predicted. There is certainly the potential for some areas to pick up 10″ or more of snow in tomorrow’s, especially across southern and eastern portions of the metro area and certainly across the Palmer Divide.
On the flip side, if the system exits too quickly to the east or the changeover from rain to snow is delayed, then snowfall amounts would be reduced. Regardless, preparation should be made to consider this a high impact event given the high winds (which is a near-certainty) and the upper-limit potential for heavy snow, which could cause serious problems on the roads.