John McGinley, Boulder County.  November 2018: Precipitation was just about normal and nicely distributed with nearly every week having some snow. The upper air pattern favored a northwesterly flow that brought cool air from the north alternating with and strong westerly flow over the Divide. This combination often brings snowy and cooler conditions to the Peak-to-Peak region. Canadian air moved southward over Colorado giving us our second month in a row with cooler than normal temperatures. Mid-month we had two upslope events that brought nearly a foot of snow. As is normal, we had quite a few windy days that brought days of blowing snow.

Precipitation: Precipitation was a little below normal with 1.06 inches realized from 17.6 inches of snow. Seasonal normals are 1.12 and 17.9 inches, respectively. The biggest event was 9 inches on the 10-11th. We had good distribution too, as every week had a precipitation event.

Temperature: The average high was only 35.6 degrees F with an average low of 21. This put the mean temperature 1.7 degrees below normal for the second month in a row, as October was also below normal. Warmest high was 47 degrees F on the 16th; the coldest high was 19F on the 12th. The coldest day had a low of 1 degree F on the 11th.

Winds: It was very windy (but not unusual for November) with 11 days at 40+ mph and two days over 60 mph. Peak wind was 65 mph on the 2nd.
Other features: Persistent northwest flow puts Colorado on the borderline between Pacific and Polar airmass surges. We can pick up snow from either upslope flow or moist flow over the Divide. Usually snow amounts are modest. The big snow this November was only 9 inches.

Outlook for December: We are already nearly halfway into the month. So far it has been cold every day, cooler than normal. Snow has been sparse with only a couple of inches falling. Windy days are on track. We have a long way to go to the end of the month. By then we should approach the averages: around 35 degree highs, around 15 degree lows, 14 windy days and 18 inches of snow melting out to 1 inch of liquid. Long range models are showing a tendency for more straight westerly flow that should warm things up and reduce the potential for heavy snow. Winds are likely.