The Ides of March may bring some precipitation

6:30 AM, Thursday, March 15, 2018

There is actually a chance for measurable precipitation late today or this evening along the Front Range urban corridor. It will likely be showery in nature, so some areas may get missed. The best chances are north of Denver, and there may be some pockets of briefly heavier showers with thunder. For the lower elevations it is likely to be mainly rain, but there could be some small hail or snow in some of the heavier pockets. Cheyenne has a better chance for some measurable snow. And snow is likely in the mountains.


This storm will pass quickly and mild weather is likely through much of the weekend. But a similar type of storm (except maybe a few degrees colder) may move into the area late Sunday.




Weekend outlook: darker mornings and brighter evenings by Sunday

11:45 AM, Friday, March 9, 2018

Since the weather won’t be too exciting, the change to Daylight Saving Time might be the most noticeable thing this weekend, and quite easy to forecast.


But there is some change in the weather on the way. A Pacific cold front will sweep through the state late tonight and Saturday bringing localized areas of snow to some of the high passes and mountains, mainly north of I-70. For the Front Range foothills and plains there is very little chance for precipitation with the front, but there may be a period of gusty northwest winds. Afternoon temperatures are likely to be about 10-15 degrees cooler than today, which still isn’t too bad. The dry weather should continue into Sunday. A storm passing south of the state on Sunday may bring some high elevation snow to the San Juans and Sangre de Cristos, but nothing major.



Change coming late in the weekend

1:30 PM, Friday, March 2, 2018

The weekend should start out springlike Saturday, but a change colder and moister for the mountains is likely Sunday. The Front Range may not see the cooler weather until late Sunday.

Front Range foothills and eastern plains

Saturday should be another mild day, but high level moisture ahead of a Pacific storm may cause more cirrus clouds than we see today. The mild weather should continue into Sunday until the axis of the Pacific storm moves through late Sunday or Sunday night. Other than a chance for brief showery snow and rain, it should be mostly or entirely dry for the foothills and eastern plains. The most noticeable change may be the tendency for strong gusty northwest winds ushering in the cooler weather by Sunday evening.


Mountains and West Slope

After a mild Saturday the Pacific storm that is bringing much-needed rain and snow to California will begin to move into western Colorado Sunday. It will loose some moisture along the way, but there will likely still be enough to cause enough snow for wintry conditions on the high passes Sunday and Sunday night. Around 6 inches is probable in the high mountains and west-facing slopes.

More snow later today

9:00 AM, Friday, February 23, 2018

Colder than average weather, but not extreme cold, should be with us through the weekend. Snow is likely by this evening in the Front Range urban corridor, possibly early enough to have some impact on the evening commute.


A broad upper level trough in the West has kept it cold and is sending occasional disturbances through the Front Range region. Snow last night was quite minor in most places except a portion of northern Jefferson County where about 4 inches fell in a short period around Arvada and Wheat Ridge.


Another disturbance is likely to result in widespread minor accumulations (mainly from Denver northward) late this afternoon and evening. But once again some narrow bands of heavier snow oriented southwest-northeast can result in 1-4 inches very quickly for a subset of the area. Watch for rapidly changes conditions.


The weekend should be mainly dry (except some snow in mountain areas). Temperatures will remain below average, although they may rise above freezing along the Front Range. No dramatic warm-ups are likely over the next 5 days


Below average temperature all week after record lows today and tonight

Noon, Tuesday, February 20, 2018

Cold weather will continue all week, but less extreme after Wednesday. Some intervals with clouds and flurries are possible late today and again Thursday afternoon into Friday.

Record Cold

Boulder got down to -6 this morning eclipsing the old record of -1 set in 1918. DIA got down to at least -3 from what I can tell which was not a new record. DIA is often one of the coldest locations in the Denver area, but low clouds hung on a little longer out there preventing ideal radiational cooling.


Tonight the record is -2 in Denver (1955) and +4 in Boulder (1911). In both cases they are the warmest record lows in February (and in Boulder’s case the only one above zero). There is a chance of getting down to the record tonight, especially in Boulder.


Today’s record low maximum temperatures are 16 in Denver (1911) and 17 in Boulder (1918). It’s possible we will stay colder than that in at least one location.


Cold and unsettle this week

The record cold will pass, but below average temperatures will continue for the rest of the week.

A storm system to our west is close enough to result in some periods of clouds and light snow at times through the week. Late today is one period where some light snow or flurries are possible, with very minor accumulations of a half-inch or less, mainly south of Larimer County.

Another period when the chance of light snow or flurries increases is late Thursday through Friday. That too looks minor.

The good news is that the mountains of Utah and southern Colorado, where the snowpack is well below average, are finally getting some. It’s not enough to erase the snow deficit, but it helps. In northern Colorado the mountain snowpack is not as bad, and they are getting some snow too this week.



More snow by Monday evening, cold week

11:30 AM, Monday, February 19, 2018

Expect snowy conditions to continue (and maybe get worse) through this evening from metro Denver northward with very cold weather through Tuesday.



The periods of intermittent light snow should continue through the night. More important is the likelihood for narrow southwest-northeast bands of heavy snow late this afternoon and evening. These bands parallel the jet stream and may only be 10-15 miles wide but a hundred miles long, so conditions can vary greatly over short distances. Most of the best local scale models are predicting a main band stretched from the north and west sides of metro Denver to Weld County. I don’t completely trust the forecast of a specific location, but a period of heavier snow in a small area somewhere from metro Denver northward seems likely.

Total accumulations through Tuesday morning from metro Denver north are likely to be 2-4 inches in most areas, with 4-6 associated with the heavier bands late this afternoon and evening. Colorado Springs will likely be south of the main action.



Many parts of the Front Range urban corridor may not see temperatures rise above 20 until Wednesday. Nights will probably be in the single digits, and if there is partial clearing Tuesday night some of the normally cold spots might slip below 0. Even though it won’t be as cold later this week, we will probably remain a below average with some potential for more cloudy intervals and light snow.

Cold, wintry weather coming

Noon, Sunday, February 18, 2018

The 3-day weekend will end much colder than the first two days, with some snow, mainly  north of Colorado Springs. The cold surge is already through Casper, WY and is likely to slide down the Front Range tonight. There may be some light snow or freezing drizzle by Monday morning, and a better chance for snow along with even colder air Monday afternoon and night.


Widespread accumulations of 1-4 inches can be expected from the Denver area northward, but there will probably be some narrow southwest-northeast bands of heavier snow resulting in some areas getting 3-6 inches, mainly Monday afternoon or night. With temperature in the 20s and maybe even colder by late day Monday, expect wintry road conditions.


As you go south from Denver the chance for snow decreases, with just a small chance for accumulations in Colorado Springs and Pueblo.  Snowy conditions are likely at many of the high passes as well. North and west of Cheyenne heavy snow and wind may force some road closures.


Very cold weather will continue through Tuesday.