For the better part of a week, the European model has been suggesting that a storm would come together and bring the Southern Mountains their first best shot of widespread snow of the year between the 28th-31st. The other models struggled with this solution but have lately come to this line of thinking over the last couple of model runs.
I am happy to see how this has come together because it indicates one thing to me, the GFS winter bias has finally caught up with the new version of the GFS. If you remember this new version of the GFS officially replaced the old version in late spring, one of the weaknesses of the favorite model of NOAA, is that it attempts to take winter storms from west to east too quickly, it usually corrects right before the storm hits but not always. If you have followed me for a while you may remember the story of the storm (I believe) in December 2009 when the GFS was predicting 1 inch of snow for the Durango in town area and the NWS swallowed that bait and used that in their point forecasts, the storm dropped in further west than expected and 15-20 inches of snow fell. That particular event was part of the impetus for creating the Facebook page that started all of this. My thought was how can anybody miss a forecast that bad?
There is a big difference in my opinion between the staff at the Grand Junction NWS then and now. My argument in the early days of the page was that they literally would run from a forecast and ignore Durango, and not follow up after making a forecast. There was a bit of a change of staffing that literally ended up with a drunk forecaster from there getting on my page and calling me an ass, to which hundreds of followers came to my defense. Most of the people there are new in the last few years especially the higher leadership and lead forecasters and I really appreciate how much more time they devote to our area.
Here is the bad news, the storm track next week still does not favor us for a lot of snow. However, Denver will likely see one of the snowiest Octobers ever and will likely set a record for all-time October low temperatures, in fact, near or below zero temps may be possible mid-week for Denver.
At the moment, it looks like flakes will be flying for most areas when we wake up Monday morning, it looks like the second storm will mainly affect areas of the northern and central mountains and areas east of the divide. I am not confident yet that we will have any accumulations south of the La Plata and San Juan County border. I will be tracking that second storm over the weekend, hopefully, we will get some more westward correction with the second storm. Either way, Wolf Creek will again be the winner next week (in our area) which will be great for their opening next Thursday!
So to recap snow should start flying in SW Colorado early Monday morning, in Denver light snow could start as early as Sunday afternoon and get heavier Sunday night into Monday. Snow should move out of the state by Monday afternoon, Tuesday afternoon/evening the second storm should move in, again mostly for Denver and the Central and Northern Mountains, but areas north of Purgatory may also see some light snow from early Wednesday morning to Wednesday evening.
Here is what that looks like. This starts on Sunday night at 8 pm and goes through Wednesday evening. The darkest areas of blue the heavier the bands of snow.
I am going to hold off on posting accumulations until Sunday, but if you are going to be traveling across the state between Sunday night and Monday afternoon, and Tuesday night through Wednesday night there will likely be impacts to the highways.