December 2019 Climate Summary for Eastern Utah and Western Colorado

*Please note that all data mentioned is collected from our automated observing stations from 10 different airports across eastern Utah and western Colorado. Some of our cooperative observers in more remote areas may have measured warmer or colder temperatures, or more or less precipitation than what was mentioned in this summary.*

Periodic, light snow showers kicked off December as a quick moving Pacific disturbance trekked across the mountains of eastern Utah and western Colorado. Another, more hearty upper level trough moved through the first weekend of the month and produced generally 5 to 10 inches of snow for the western Colorado mountains with locally higher amounts exceeding a foot across the north. Dense fog developed for the next few nights in the wake of this system as low level moisture remained trapped in the lower valleys. December 12-16th saw a long duration atmospheric river event impact the region which brought moderate to heavy snow over the western Colorado mountains as well as some higher elevation valleys. Generally 1 to 2 feet of snow fell across the Elkhead and Park Mountains with an average of 8 to 16 inches for most of the other mountains. Some of the higher elevation valleys, including the Upper Yampa and Central Colorado River Basins, saw 3 to 8 inches of snow in a short amount of time. This storm also produced wind gusts of 40 to 50 MPH in the mountains with gusts up to 75 MPH above treeline in the San Juan Mountains. High pressure moved into the region in the wake of this storm with conditions remaining dry leading up to Christmas Eve. After that, a Pacific trough moved into the Great Basin and produced moderate snowfall over the southern mountains through Christmas.

The northerly and southerly tracks many of the storms took during the month of December allowed several climate sites to end the month with above normal precipitation reported at 5 out of 10 of the automated stations found at airports across eastern Utah and western Colorado. The most precipitation fell at the Craig-Moffat Airport where 1.75 inches fell...0.75 inches above normal for December. The Rifle Garfield County Airport saw the least amount of precipitation with only 0.20 inches...0.64 inches below normal. December was warmer than normal for most of the region with mean temperatures ranging anywhere from 0 to 3 degrees above normal. The warmest December temperature of 52 degrees F occurred at the Canyonlands Airport in Moab, Utah on the 8th. The coldest temperature of -16 degrees F occurred at the Craig-Moffat Airport on December 31st.

Grand Junction had an average monthly temperature of 30.8 degrees which was 2.3 degrees above normal. The highest temperature was 50 degrees on December 6th and the lowest was 9 degrees on the 18th. 0.55 inches of precipitation fell throughout the month which was 0.04 inches below normal. 2.5 inches of snow fell which was 2.4 inches below normal.

Taking a quick look ahead to January, the official forecast from the Climate Prediction Center (https://www.cpc.ncep.noaa.gov/products/predictions/long_range/lead14/) shows odds of below normal temperatures across eastern Utah and western Colorado with no real guidance favoring either above or below normal precipitation across the region.

For more climate information from other sites, please visit our climate page on our website at http://w2.weather.gov/climate/index.php?wfo=gjt (select the NOWDATA tab for even more sites). You can also follow us on Facebook (@NWSGrandJunction) or Twitter (@NWSGJT).