Sunday, November 29, 2015
The wobbly and slow-moving storm in the Great Basin is beginning to move eastward today, increasing the chances of snow tonight through the day tomorrow and likely through Monday night as well. Though cold temperatures will be observed as the storm moves over the Steamboat Springs area Monday, winds don’t turn to the northwest until midday tomorrow, limiting overall snowfall as moisture decreases behind the departing storm.
I would expect the standard-for-this-Thanksgiving-weekend 1-4” to be reported tomorrow morning and another 3-6” to be reported Tuesday morning, with most of that falling during the day and early evening Monday. Temperatures will stay cold through Tuesday, before some warming will be observed at the higher elevations by midweek, while the valley stays cool as the standard temperature inversions form.
Temperatures will likely be warmest around the end of the work week as southwesterly winds increase and possibly mix out the valley inversions before another weak and splitting storm is forecast to affect our area by early in the weekend. At this time, only light snow is forecast for a short period of time around Saturday before the storm is past.
There is model disagreement early in the following work week, with the American GFS predicting a weaker, drier and faster moving storm than the European ECMWF.
Tuesday, November 24, 2015
The chances for snowfall Thursday and possibly Friday look good, though models have trended significantly weaker with the storm for the Steamboat Springs area. The storm is currently located along the Oregon coast, and is forecast to move first southward and then eastward before stalling in the western Great Basin by Thursday. A couple of lobes of energy look to be ejected near our area on Thanksgiving day and again Friday, and though light snow may possibly be falling until Friday night or Saturday morning, the amounts look to be confined to around 1-3” for each day.
A break in the weather is forecast by later Saturday into early Sunday before a Pacific wave moves through the southern portion of the Great Basin low and moves over our area later Sunday. Though precipitation should increase by Sunday afternoon, temperatures will warm as the southwesterly flow increases. This wave does force the Great Basin storm to begin moving eastward though, and I expect the best snows to occur after the storm moves over the area and cool and moist northwest flow is established by early Monday.
Colder air is forecast for later Monday, but moisture begins to decrease as the coldest air arrives, likely limiting snowfall by Monday afternoon and ending it by Monday night. Tuesday will start off chilly, and dry weather with warming temperatures should be noted for midweek as a shallow and transitory ridge moves over the area.
There is a chance for a storm near the end of the work week or next weekend, but confidence is low due to the uncertainty related to the movement of the Great Basin low early in the forecast period.
Thursday, November 19, 2015
The current light snow on hill will continue through the night before increasing as a moderately strong but quick-moving wave passes over the Steamboat Springs during the day tomorrow. Temperatures should cool noticeably through the day Friday as the cold front moves through the area. Snowfall amounts of 5-10” on the hill and about half that in the valley should fall by Friday afternoon, with the snow ending during the night.
Skies should clear by Saturday morning bringing the coldest temperatures of the season under mostly sunny skies. A wave which I thought might develop into something more substantial for Sunday looks to stay north of our area, possibly bringing some high clouds and keeping temperatures cool.
Monday should be sunny and warmer, with clouds increasing starting later Tuesday and into Wednesday ahead of a major storm traveling over the Gulf of Alaska and making landfall around Tuesday. Unsurprisingly, there is disagreement between the models as to the location and timing of this storm as it moves across the Great Basin and likely affects Colorado by Wednesday afternoon.
It appears likely that an another wave dropping southward from the Canadian Plains will bring additional energy and cold air into our area around Thanksgiving Day, but how this affects the overall evolution of the storm is currently unclear.
Tuesday, November 17, 2015
The Steamboat ski area reported 10” of new snow today from the storm which began early Monday morning. Snows are forecast to increase again for tomorrow and Friday, with the American GFS model bringing another quick-moving storm for Sunday. For those keeping score, the European ECMWF did a better job than the American GFS last week by keeping the storm progressive for today and tomorrow, as discussed in the last forecast, so the forecast for Sunday is uncertain.
The current cool and moist northwest flow looks to continue through the weekend, continuing the unsettled weather. Snowfall will increase again on Wednesday as a quick moving wave moves over the Steamboat Springs area. Temperatures will cool during the day and the storm should leave another 3-6” on the hill by Thursday morning.
A brief break in the wintry weather is forecast early Thursday before a similar but stronger wave brings another shot of snow and colder temperatures for Friday. If this wave holds together as advertised, another 5-10” of snow should be reported on the hill by Saturday morning.
By Sunday, the American GFS has trended significantly stronger with the next wave in northwest flow while the European ECMWF has kept the wave weaker and further north. The ECMWF’s recent out-performance notwithstanding, I do like the American GFS’s trend and would not discount that solution for more snow Sunday.
Another break is forecast for early in the work week before significant differences in the two models appear again by mid week. It appears likely we will get some sort of weather around Thanksgiving, though the details are obscure at this time.
Friday, November 13, 2015
A major storm will impact our area starting Monday after a beautiful weekend. Currently, dry air has settled over Colorado leaving the Steamboat Springs area under mostly sunny skies that will persist through most of the weekend. Temperatures will warm at the higher elevations while the valley may stay cool as the current temperature inversion persists, with high clouds invading the area later Sunday in advance of the next storm.
This storm is forecast to cross the West Coast early Sunday. Numerical models have the storm undergoing a split as it moves eastward across the Great Basin, with the dominant southern portion of the storm impacting the entire state of Colorado Monday through around midweek.
Usually, confidence in the model solutions grows stronger as an event nears, however model solutions for the Monday storm are still changing, leading to a low confidence forecast after precipitation likely starts early in the day on Monday. Uncertainty revolves around how much energy is drawn into the southern part of the split and the amount of intensification the storm is expected to undergo as it crosses the Rockies.
The American GFS has trended slower and stronger with the storm, now keeping significant snows over Colorado through Wednesday, while the European ECMWF has trended back towards the originally faster solution, moving the storm east of our area on Wednesday. Interestingly, the Steamboat Springs area may continue to receive snows in this case in the cool and moist northwest flow behind the more rapidly departing storm.
Storm amounts are tough to forecast, but it is likely we will receive 6-12” of snow on the hill and maybe half that in the valley by Tuesday morning as both models agree upon the storm motion until it crosses the Rockies. At the very least, I would expect unsettled weather with varying amounts of snow on Tuesday and Wednesday, with the possibility of heavy snows during each of those days.
Any breaks in the weather after this storm passes will likely occur around Thursday and early Friday before another Pacific wave is forecast to cross the West Coast on Thursday. This looks be a fast-moving and splitting storm, and is currently forecast to bring a cool front with light snow through the Steamboat Springs area late on Friday or early in the weekend.