By the time I finished writing the NWS issued a Winter Storm Watch, which I have included at the end.
Tonight and Monday
These storms are going to keep us guessing until the end. I did say storms. A small feature will emerge this evening and could bring some light snow or heavy flurries for the northern 2/3 of the county, but it will favor the La Platas and from Rockwood north and the 550 passes. This could keep going until around 11 am Monday, a little longer from Silverton to Ouray.
Tuesday and Wednesday
The models are still trying to bring some snow in during the morning and afternoon of the 25th, with the heaviest period of snow coming between 8 pm Tuesday and 8 am on Wednesday. I still have not seen a noticeable stalling of the storm from the models. I would prefer that. Yes snow Christmas day is nice and all, but if we want higher accumulations, we want it to stall and strengthen before it arrives!
Thursday Friday Saturday
On Thursday the storm will really intensify in SE Colorado area and move off to the northern plains. As it does that most models indicate some more snow wrapping around the low and moving into the area. Either that or they are trying to sniff out something that the storm leaves behind. By Friday, another storm could move into our area. the GFS is trying to make this a bigger storm than the first. The Euro has not gotten to that stage yet. One thing that makes it exciting is cold air should be deeply entrenched in our by that time. After that, there are some preliminary indications that we could see something around New Year’s day, I am not going there yet let’s just try to get through the week and in a few days, I will start looking at the next two.
Since there will probably be very little downtime (especially above 9,000′) I am going to group the accumulation totals with the models.
The Euro was on a good streak but was a little more apprehensive on this run. The GFS is more bullish on the second storm and what is more exciting is is that if the models are correct the high on Friday could struggle to hit the mid 20’s in town with mid to upper teens at Purgatory. These temps are very efficient for snow production so they could trend higher than what we see from the models. While I am just showing the GFS and Euro, I can tell you the new experimental GFS (FV 3) has had more significant totals than either of the other two. Here is the (old) GFS totals include both storms.
COZ018-019-240600- /O.NEW.KGJT.WS.A.0007.181225T1600Z-181227T0400Z/ Northwest San Juan Mountains-Southwest San Juan Mountains- Including the cities of Telluride, Ouray, Lake City, Silverton, Rico, and Hesperus 145 PM MST Sun Dec 23 2018 ...WINTER STORM WATCH IN EFFECT FROM TUESDAY MORNING THROUGH WEDNESDAY EVENING... * WHAT...Heavy snow possible. Total snow accumulations of 8 to 16 inches possible with locally higher amounts. Winds could gust as high as 30 to 40 mph. * WHERE...Northwest San Juan Mountains and Southwest San Juan Mountains. * WHEN...From Tuesday morning through Wednesday evening. * ADDITIONAL DETAILS...Holiday travel could be very difficult. Blowing snow could significantly reduce visibility.