Our short break of calmer, mild and dry weather is about to come to an end as we watch yet another storm move into the area. This time around, it’ll looks like temperatures will support mostly snow so the forecast in that realm, is easier. The tricky part comes with the location of this storm and a secondary chunk of energy that’s going to make our main system wobble. And that wobble could be the make or break for snow totals in some areas. Regardless, snow is coming but is this the “big” one? Maybe not. There could be more impacts from this one though since it’s a bit colder.
Saturday and Sunday will be mild and sunny with clouds building Sunday ahead of the incoming storm. Either way, here’s a view of the upper level pattern that I’m monitoring.
Okay, so on Sunday two distinct chunks of energy are draped across the western US. These are the components of our next storm. I’m showing the EURO model above because it has been the most steady in location of the storm but it is not the solution that is favoring a lot of snow for our area. Regardless, the southern chunk will push more easterly while the northern chunk will move SSE from Idaho to Arizona. As they move close to each other and interact, what’s known as the Fujiwhara affect might lightly start to happen. Essentially what that is, is when two areas of spin begin to interact with each other, they push and pull and “dance” around one another.
All of the solutions are showing a windy afternoon shaping up for Sunday. Especially further east as these systems approach. Winds along the Urban Corridor with be 10-15 mph with gusts to 25 mph but on the eastern Plains, winds will be sustained near 20 with gusts to 40mph or higher. High fire danger will be a concern Sunday. Eventually, a cold front will push through in the afternoon/evening producing some upslope flow overnight into Monday. Mountain locations will see snow begin Sunday evening with the metro areas possibly waking up Monday to light snow.
By Monday, the southern chunk of energy begins to push east as the northern chunk of energy dives south being absorbed into the other. What happens after this is these two features fight to move east with the main flow but with slight perturbations north at times. Those slight perturbations are what could deliver good upslope winds to Boulder and Longmont Tuesday, or they could be the winds that produce less snow for those areas (which is what happened to Boulder the last storm).
Models have been honing in on a solution but some (the GFS) are still painting a pretty decent storm over Denver and the adjacent higher elevations. All models have a low cutting off from the main flow near northern Arizona and moving east. The GFS is showing this storm moving into SE Colorado which is a great position for a big storm for us. The CAN and the EURO are showing a storm moving into east central New Mexico, a bit far south to produce big totals.
We do know that adequate enough upslope winds will allow for snow to fall region-wide but talking totals is a bit difficult because winds have such an impact on totals. For now, yes, it’s going to snow Monday and Tuesday and there will be two distinct waves to this storm. One Sunday overnight into Monday morning and the second Monday night into Tuesday.
The NBM (National Blend of Models) averages out what the all of the models are saying and is a generally good source to use. It shows how a NE Wind can really impact an areas snow totals. The Cheyenne Ridge is topographical feature in Northern Colorado near the Wyoming border when winds flow towards Ft. Collins off of this ridge, they dry and warm. The Palmer divide is a topographical feature in between Denver and Colorado Springs and when winds push from Denver to Castle Rock they get pushed up that terrain which causes air to moisten. Downslope winds off the Palmer Divide mess up Colorado Springs to Pueblo snow. Finally, the Raton Mesa is an area of higher terrain in Southern Colorado near New Mexico border. In the image above, these terrain features are very noticeable. These winds always cause sharp gradients of a lot of snow and barely any so any slight changes in wind direction can impact where heavier snow falls.
The second part of this storm comes Monday to Tuesday as steady NNE winds bring impacts the state. This storm is looking to move into the central Plains and will be in a location to deliver constant light upslope to some areas. We’ll see another round of steadier snow from Monday evening to Tuesday and this will add to the totals we see into Monday.
Right now, I like what the NBM is showing because it looks like we will have a slightly more northerly component to our winds so let’s throw out some early prediction snow totals. These are subject to change but I’ve noted the areas of concern.
Denver: 1-3” (with a potential boom depending on winds)
Ft. Collins: T-2”
Boulder: 1-3” (with a potential boom depending on winds)
Castle Rock: 3-6”
Colorado Springs: T-2”
Summit county: 3-5”
Aspen/Crested Butte: 4-7”
Wolf Creek: 5-7”
Eldora/Winter Park: 4-8”
Mountains are mainly going to see light impacts but some nice powder is expected there by Monday afternoon through Tuesday. Generally, this is not shaping up to be the “big” storm for anyone but the potential for higher totals than what is currently forecast, is there. As always, something to monitor but prepare for Monday and Tuesday to be colder and snowier region wide.
Enjoy the weather! It’s the only weather we have.