6 AM MST, Wednesday, December 12, 2018
A cold front later today will bring in a day of cooler weather before mild weather returns on Friday. Some light snow amounts are likely in the mountains this evening, but for the eastern foothills and plains little or no snow is expected. Other than the brief cool down to near average temperatures tonight and Thursday, the next week is likely to see mainly dry weather with above average temperatures throughout the region. Gusty winds are likely to develop today ahead of and following the front.
Geminid meteor shower
The Geminids, on the night of December 13-14th, are one of the two best meteor showers of the year (the other being the Perseids in mid August). This year the half-moon will set before midnight, so the best time to watch is between midnight and daybreak. The chance for clear skies is good, but we always have to watch for the development of high level ice crystal clouds along and just downwind of the high mountains.
5:45 AM MST, Friday, November 30, 2018
The weekend will start seasonably cool Friday and Saturday, and then turn even colder Sunday as a polar air mass moves into Wyoming and Colorado from the north. It looks like daytime temperatures will below freezing in the low elevations on Sunday and Monday.
If you are traveling north and east into Nebraska and the far northeastern plains of Colorado (east of Sterling), or up into central Wyoming, snow and blowing snow will make for difficult travel tonight through Sunday. For the Front Range region no major precipitation is expected for the eastern foothills and adjacent plains, but periods of clouds and some minor precipitation is possible.
The first chance of precipitation is this afternoon and tonight. Light snow accumulation is likely in the high mountains and west-facing slopes. Watch for icy conditions at the passes tonight and tomorrow morning. For the urban corridor some rain or snow showers will be around, but little or no accumulation of snow is expected. The next chance of snow for the eastern foothills and nearby plains is Sunday afternoon or night. Only light accumulations around and inch or less appear likely right now.
7AM MST, Saturday, November 24, 2018
Another Pacific cold front today will be stronger and more moist than the one Thursday night. Snowfall in the mountains and West Slope will intensify today. Winter travel can be expected over the mountain passes and on wind-prone stretches of I-70 and I-80 west of Denver and Cheyenne.
Although the Front Range foothills and eastern plains will not get a major winter storm, the front passage will be noticed here too as strong gusty northwest winds and some localized snow squalls. The wind is likely to kick in later this morning or early afternoon as the front comes through. Some snow showers from the west side of the continental divide will probably spill over to the east side. Brief squally snow showers are possible in some areas. Although the snow should be brief, it may quickly whiten the ground (less than and inch) in some locations while nearby locations have nothing. Nearer to the continental divide (west of Peak to Peak Highway) several more inches of snow are likely today.
Chilly, but dry and less windy weather is in store for Sunday.
6:20 AM MST, Thursday, November 22, 2018
Happy thanksgiving. Travel conditions will be good today. If you are returning to the Front Range region from the west on Friday/Saturday, prepare for some winter travel conditions.
Front Range East Slope and Eastern Plains
A Pacific cold front will move through the region tonight. Little or no precipitation is expected in the lower foothills or plains. 1-4″ is likely closer to the continental divide (west of Peak to Peak Highway). The main impact for lower elevations will be cooler temperatures Friday and some areas of strong west-northwest winds late tonight and Friday. Some areas near the foothills may see gusts around 60 mph.
A stronger Pacific cold front on Saturday will cool it off some more and result in more strong wind from the northwest. That one may bring some localized areas of snow for the foothills and plains, but little accumulation is expected in eastern Colorado. However, as you get closer to the continental divide enough snow should make it over from the west side for 3-7 inches along with blowing snow and cold wind chills in places like Rocky Mountain Park and Brainard Lake.
Mountains and West Slope
A Pacific cold front should bring 3-6 inches of snow tonight and Friday morning in the higher elevations and west-facing slopes. After a relative lull, a more powerful surge of Pacific moisture should bring areas of heavy snow and blowing snow late Friday night and Saturday. Some snow accumulation is likely throughout the West Slope, with 12-18″ near the ridge lines and west-facing slopes. Difficult travel conditions are likely at the high passes and other areas that are prone to high wind. The worst conditions are likely along and north of I-70. Wind and snow should let up by Sunday.
6 AM MST, Tuesday, November 20, 2018
Mild and dry weather will be in place for Colorado and Wyoming from now until Thanksgiving Day. Two cold fronts are expected to move west-to-east across the region, one Thanksgiving night, and another on Saturday with mountain snow.
The weather should not impede your ability to get to you destination on Thanksgiving. A Pacific cold front on Thursday night should have little or no effect in the Cheyenne to Colorado Springs corridor other than to cause a few localized sprinkles or snow showers, and make it a bit cooler on Friday. Light snow accumulation is likely in the mountains by Friday morning.
A stronger and colder storm system on Saturday is likely to bring significant snow to mountain areas and west-facing slopes. For the Front Range urban corridor the impacts, other than colder temperatures, are likely to be minor due to the lack of upslope flow. But the exact path of that storm is still a bit uncertain. I’ll update on Friday in case it appears the chance for snow along the Front Range becomes more likely for Saturday.
5:45 AM MST, Friday, November 16, 2018
Expect a cold weekend with some snow around on Saturday, and sun returning on Sunday. A strong cold front should move north to south through the Front Range region this evening followed by low clouds. It may take until morning for the clouds and colder weather to get into the higher elevations. Temperatures on Saturday are likely to stay in the 20s all day throughout the Front Range urban corridor and then return to the 40s Sunday afternoon.
Initially the middle and upper parts of the atmosphere might be somewhat dry. That limits the cloud depth and the generation of larger snow crystals. So we may see some areas of light snow, snow grains, or freezing drizzle late tonight and early Saturday. On Saturday we are likely to transition to all snow where there is precipitation.
Accumulations are expected to be on the light side, with the highest amounts in the northern Front Range region, and little or nothing down in Colorado Springs.
3-5 inches: Cheyenne
2-4 inches: Fort Collins
1-3 inches Denver-Boulder metro
0-2 inches south of Denver
7 AM MST, Monday, November 12, 2018
The weekend storm was not only stronger than expected, but it took a path farther west of Colorado putting the Front Range region in stronger and much more persistent easterly upslope flow than had been expected. Many areas got on the order of 6 inches. In and along the lower foothills of Boulder County seemed to be the sweet spot where up to 15 inches fell. The Boulder Climate Station had 13.4″ of snow which contained 0.68″ of liquid.
For those who love snow, you had a pleasant surprise. For those who don’t, dry weather will rule this week after some Monday morning flurries. A return of afternoon temperatures in the 50s will be in place by Wednesday, so the snow will soon be history.
The next cold front and chance for snow is lurking for this weekend.