12:30 PM, Wednesday, April 15, 2015
We are more certain about the storm track today and it is looking likely that there will be heavy precipitation in the Front Range region from Denver to Cheyenne. The big uncertainty today is whether it will be cold enough below 6000 feet to result in heavy snow.
A cold front has moved across the Wyoming border into Colorado at noon, and this afternoon will start turning cooler. Showers and maybe a thundershower may develop, especially along the Front Range north of Boulder County and in Wyoming.
The heaviest part of the storm is likely Thursday and Friday in southeastern Wyoming and near the Wyoming border in Colorado. For the Denver-Boulder area and the nearby foothills, it will likely be late Thursday and Friday when the heaviest precipitation occurs.
The atmosphere should be cold enough for snow down to lower elevations Wednesday night and Thursday morning, but there will likely be little if any precipitation, except to the north in and around the Cheyenne area. During the day Thursday the atmosphere is likely to become more moist and a little warmer throughout the area, probably too warm for snow below 7000 feet. Although it will cool off once the precipitation intensifies late Thursday, it might not be enough to push the snow levels much below 5500 feet by Friday morning.
For the mountains of the Front Range from metro Denver to Laramie: heavy wet snow, 1-2 feet by Friday night; 6-12 inches between 6000 and 7000 feet where it will likely start as rain.
Urban corridor, Denver-Boulder-Fort Collins- Cheyenne: Mainly rain in Colorado, but some wet snow accumulation is likely Thursday night into Friday morning. The accumulation may be very variable from 0-6 inches. In the Cheyenne area there is a better chance for heavier accumulations. For the Denver-Boulder area, we can’t rule out much heavier snow if the temperature is just a degree or two colder, but right now that looks like a small chance, maybe about 20%. The total liquid (rain plus melted snow) will probably range 1-3 inches in and along the Front Range from the Denver area northward. Precipitation is likely from Colorado Springs southward, but it appears that area will be south of the heaviest precipitation.