12:15 PM, Monday, December 14, 2015
Expect accumulating snow late tonight and on Tuesday morning to impact ground and air travel. The highest impacts are likely in the Cheyenne area and on the northeastern plains of Colorado, with moderate impacts for the Denver-Boulder-Fort Collins corridor, and minor impacts in Colorado Springs.
Monday Evening: the chance for snow increases in mountains , especially in southern Wyoming and central Colorado.
Late tonight and Tuesday morning: main snowy period for the Front Range and adjacent plains. Increasing winds on the Colorado plains and in the Cheyenne area. 3-9 AM will be probably be the peak snowfall period.
Tuesday afternoon: snow tapers off from west to east. Maybe some significant snow and blowing snow out east on the high plains of northeastern Colorado.
Mountains: generally 6-12 inches, highest accumulations in north-central Colorado (around Vail Pass and Steamboat). Nederland is likely to be on the lower end of that range.
Cheyenne area: 5-8 inches, blowing snow.
Metro Denver-Boulder-Fort Collins: 2-5 inches. Blowing snow, especially east of I-25. A slight shift in track could result in little or nothing, or add a few more inches, but that appears to be a very small chance at this point.
Colorado Springs: 0-2 inches
Bottom line: A paralyzing storm is not expected, but winter travel conditions are expected by Tuesday morning. The worst conditions won’t necessarily be in and near the foothills.
3:20 PM, Sunday, December 13, 2015
Another fast-moving winter storm will become more intense as it moves eastward from Colorado into the Great Plains late Monday night and Tuesday. The current expected track puts the greatest risk for a period of heavy snow and wind in eastern Wyoming (including Cheyenne), with lower risk of heavy snow in the Denver-Boulder-Fort Collins corridor, and very low risk from Colorado Springs south.
Will update tomorrow. Right now most probable looks like:
- Cheyenne: about 6 inches, locally up to 10, with blowing snow, peak snowfall rates early Tuesday
- Denver-Boulder-Fort Collins: 1-4 inches, mainly Tuesday morning
- Colorado Springs: 0-2 inches
The annual Geminid meteor shower peaks in the pre-dawn hours on Monday. It’s one of the two best meteor showers of the year (the other being the Perseids in August).
12:15 PM, Friday, December 11, 2015
A intensifying storm system will track through Colorado tonight and become a potent storm as it moves east of the Front Range Saturday afternoon. The Front Range region will likely see at least a period of snow Saturday, and a generally cloudy and cold day.
Mountain accumulation Friday-Saturday: 6-10 inches near the continental divide, 3-6 inches foothills (including Nederland)
Lower elevation accumulations (mainly Saturday, maybe a little Friday night):
- 60% chance for 2-5 inches (including Colo Springs-Denver-Boulder-Fort Collins- Cheyenne)
- 20% chance of more than 5 inches due to a period of localized heavy snow (in a small portion of the area)
- 20% chance of less than 2 inches (a little greater chance for this outcome in Colorado Springs).
Why are strong storms not producing big snows?
We have been in a pattern since early November of intense storm systems that do most of their intensification as they pull east of the Front Range. This limits the “upslope” flow and most of the region gets a relatively minor snowfall, while a small portion (not necessarily near the foothills) gets a period of intense snow. One of these times we might get surprised with widespread heavy snow, but I don’t think it’s this time.
Another strong storm system is due in the area late Monday, but once again it may not be the kind to produce widespread high impact snow. But it’s still worth watching.
12:15 PM, Thursday, December 10, 2015
Cooler air will start to move into the Front Range region on Friday, and then colder with clouds and some snow Friday night and Saturday.
Most probably accumulations:
3-6 inches lower foothills and plains (maybe a little less on the high plains east of Denver).
6-10 inches mountain areas, heaviest north I-70.
Northern Colorado mountains and Cheyenne area may see the first accumulating snow late afternoon or early evening Friday.
Lower foothills and plains (Denver-Boulder) probably won’t see the first snow until after dark Friday evening.
Uncertainty about heavier snow:
The storm will become stronger as it moves east-southeast across Colorado and into Kansas/Oklahoma. If the intensification occurs a little sooner, the potential for somewhat heavier snow goes up. That appears to be an unlikely scenario at this time. I will update tomorrow.
2:50 PM, Tuesday, December 8, 2015
Our current mild stretch is likely to come to an end on Friday. It appears we may be in for some snow by Friday evening, possibly extending into Saturday. I’ll update that development tomorrow or Thursday.
Until then we should remain milder than average through Thursday night. Sporadic periods of gusty west winds are likely in and near the foothills. The best chance for very strong gusts (over 70 mph) is late Wednesday into early Thursday. The winds (high wind versus little wind) will vary greatly over small distances. Stay alert in the usual windy places.