Big snows on Thursday and Friday
Wednesday, February 5, 2020
The Steamboat Springs area saw a cold start to this Wednesday morning, with a low temperature of -9 F at 7:35 am at the Bob Adams airport and -14 F at 1:50 am at the top of Mt. Werner. A Pacific jet stream will bring warming temperatures, wind and copious snow on Thursday and Friday before we see a short break on Saturday. A couple more storms bring chances for much less intense snow almost each day for the upcoming week, with midday Monday through midday Tuesday currently looking the driest.
I have to say it is tough to contain my excitement over the forecast snow amounts for Thursday and Friday. What meteorologists refer to as an atmospheric river, or well-defined stream of moisture, will round the top of a ridge of high pressure in the eastern Pacific and bring periods of moderate to heavy snowfall for the better part of two days, along with difficult to even impossible travel. Being of northern Pacific origin, temperatures are forecast to rise through today and tomorrow as the current arctic air mass is displaced, reaching around 15 F by sunset on Thursday as snowfall rates increase and approach an inch per hour.
Snowfall should start this evening, with modest accumulations of 2-5” by the Thursday morning mid-mountain report. Another 5-10” of snow is expected to fall during the day and evening along with increasing northwesterly winds before we may see a lull around midnight ahead of a wave embedded within the favorable and moist northwest flow.
Snowfall rates will increase soon after midnight and reach rates almost double that observed on Thursday. It should be snowing hard at report time, and with the 5-10” from the previous day, I would expect 8-16” of snow by the Friday morning report, based upon the latest weather forecast data which has decreased snow totals from earlier runs a bit.
So we should see some Steamboat Magic on Friday, where there are significant accumulations between report time and ski time. Northwest winds should increase in the morning and become gustier before snowfall is expected to taper off during the late morning as the embedded wave passes. But showers, some producing briefly moderate to heavy snowfall rates, should continue in the afternoon with the storm mostly over by the evening. Most of the 4-8” of snow reported Saturday morning should have fallen during the day Friday, though showers are expected to persist overnight.
Meanwhile, another storm develops in the Gulf of Alaska on Saturday and drops southward along the West Coast and splits on Sunday. We should see a break during the day Saturday before the northern part of the split brings a cold front through our area around Saturday night, with 2-5” of snow possible by the Sunday morning report. Though it is uncertain, we may also see some energy eject out of the southern part of the split storm and move over the front, which should restart light showers after a short break Sunday morning that last into Monday morning.
The last half of Monday into the first half of Tuesday look like the driest period of this upcoming week before another strong storm rounds the ridge of high pressure in the eastern Pacific and forces the southern part of the earlier split storm near our area by Tuesday night. Unsettled weather is forecast for Wednesday as this storm passes mostly to our south, with more cold air and snow possible after midweek depending upon the eventual track of the next storm.
Snow and cold for the work week ahead
Sunday, February 2, 2020
The cold temperatures in downtown Steamboat Springs this Sunday morning are warming nicely under bluebird skies, with noontime temperatures of 18 F at the Bob Adams airport and 33 F at the top of Mt. Werner. A big change comes tomorrow as a strong and complex storm moves across the area, bringing a sharp cold front and snow for a time. Bitterly cold but drier arctic air settles into our area for Tuesday and Wednesday before the snow machine cranks up for Thursday and Friday. We may see a break on Saturday before more unsettled weather may approach as soon as the end of next weekend.
A cold and strong storm is forecast to move across the Great Basin tonight. The storm is forecast to elongate and eventually stretch from Hudson Bay to Baja by midweek, which makes for a difficult forecast as there is no strong center of circulation to force definitive weather. It appears the cold air will arrive in several waves starting Monday, with colder temperatures and some snow arriving within a few hours of noon. Additional waves of cold air and snow look to occur during the afternoon and evening as an ill-defined storm center passes nearby. While we will see snow around the surges of cold air, we never get into favorable northwest flow, so I am not that optimistic on snow amounts. With further changes in the evolution of the storm likely, I would guess only 1-4” of snow during the day Monday with another 1-4” during the evening, and I hope that I’m wrong. Travel may be difficult at times during the heaviest showers from Monday afternoon through the evening.
What is more certain are the bitterly cold temperatures, with falling temperatures through Wednesday morning. Mountain-top high temperatures will be around zero on Tuesday and struggle to reach that mark on Wednesday, with cold valley high temperatures in the low teens or single digits. And if skies clear Tuesday night, Wednesday morning will bring low temperatures well below zero for the coldest night in a while.
Behind the storm, a ridge of high pressure builds over the West, bringing warming temperatures by Thursday at all elevations. However, Pacific moisture and energy is forecast to deform the ridge and bring a period of very favorable northwest flow for Thursday and likely Friday. Snows are likely to be heavy to moderate and persistent for at least Thursday, and likely Friday, where weather forecast models disagree. With mountain-top temperatures in the teens, we could see 6-12” by the time the snows get going early Thursday through Friday morning, with another 6-12” possible by Saturday morning according the more optimistic ECMWF before the snows end for at least the first half of the weekend.
However, our next storm is forecast to move southward along the West Coast during that weekend, forming an eddy in the Desert Southwest area by early in the work week. While me may see some light snows late in the weekend, the best weather looks to affect our area around the middle of the next work week.
Note that I may push by next regular Thursday afternoon weather narrative to Wednesday as details on the end-of-work-week storm evolve.
A nice weekend followed by snow and cold
Thursday, January 30, 2020
A couple of inches of new snow were on my deck this Thursday morning, which matched the two inch report at the Steamboat Ski Area. Snow will continue today before ending by around midnight, and other than a slight chance of showers Saturday morning, we should see a rare-this-season warm and mostly sunny weekend. But cold and snow return for Monday and last through the upcoming work week.
While yesterday’s storm under-delivered due to its severe and well-advertised split around our area, this Thursday storm is over-delivering, with 3-6” now expected to fall by midnight, to be tallied on the Friday morning report. As discussed in the last Sunday weather narrative, there was uncertainty with respect to how strong the wave today and Friday night would be. Weather forecast models have trended stronger with today’s storm and weaker with the Friday night storm, which is not all that unusual when there are embedded waves in the moist, unstable and favorable northwest flow.
Behind today’s storm and ahead of a strong storm developing over the Gulf of Alaska, a ridge of high pressure builds over the West. Another wave ejecting out of the Gulf of Alaska storm rounds the top of the ridge late Friday and may bring some light non-accumulating high-elevation snow showers for a short time early Saturday morning.
But the building ridge of high pressure dominates, bringing a partly sunny and warming weekend with some high clouds at times that may filter the sun. Enjoy the warm first few days of February as the Gulf of Alaska storm is forecast to make landfall on Sunday and intensify as it moves across the Great Basin on Monday. The intensifying storm will present some forecast challenges as the southern part of the storm will cut off from the main jet stream and form an eddy whose movement and strength will be notoriously difficult to forecast.
In fact, the forecasts for the storm has trended slower and deeper with the eddy, with winds forecast to turn from the northwest on Saturday to westerly and then southwesterly by Sunday, and increasing as the storm draws near.
Though the timing is likely to change a bit, and I hope to have a better idea about that by my next weather narrative on Sunday afternoon, a strong cold front will blast through our area around midday Monday, along with difficult or even impossible travel. The storm may bring some easterly winds after the cold front passes and temperatures plunge, though snows look to continue through Tuesday, in spite of the usually downward motion of air off the Park Range, as warm and moist air from the east rises within the very cold and unstable air mass.
Though Monday will start warm ahead of the cold front, temperatures will drop twenty to thirty degrees from the warm Sunday. Guessing snow amounts this far out is difficult, but 6-12” or more by Tuesday morning is possible with additional accumulations during the day, subject to change, of course.
If skies briefly clear Tuesday night, the Wednesday morning temperatures will start below zero, but regardless high temperatures will remain far below our average high of 29 F on both Tuesday and Wednesday. A ridge of high pressure behind this storm and ahead of our next one is again forecast to build over the West Coast for the end of the work week. Embedded waves and moisture will restart the snow-machine on Wednesday and last through the work week as we head into the following weekend, similar to what is occurring now.
And similar to this weekend, the weather is currently advertised to break for at least part of next weekend before we may feel the effects of the next possibly strong storm.
Snows likely Monday and Wednesday
Sunday, January 26, 2020
The partly cloudy morning on this Sunday in Steamboat Springs has finally given way to periods of sun, a welcome sight during this snowy January. A couple of incoming storms will give us good snow chances for Monday and Wednesday, with diminishing chances on Thursday and Friday night as we move through, dare I say, a mostly sunny and warm upcoming weekend.
Ahead of the first storm currently moving through the Great Basin, we should see increasing clouds by later this afternoon, along with some meager snow showers at the higher elevations, most likely in the northern portions of our Park Mountain Range.
The accumulating snow for Mt. Werner won’t start till after midnight, so I would only expect up to an inch on the Monday morning report. But snowfall intensity should increase through the morning, approaching an inch per hour at times, as the storm looks to split, or weaken, a bit less than earlier weather forecast models indicated. Snows should turn more showery after noon, with some showers producing brief, but locally moderate bursts of snow through sunset. We could see 3-6” of snow by around sunset, with lighter-intensity showers hanging on through the night in the the unstable cool, moist and favorable northwest flow. These may yield an additional 1-4” inches that would be added to the Tuesday morning report.
As showers end early in the day on Tuesday, we may see some sun as a quick-moving ridge of high pressure moves over our area ahead of next storm that enters the Great Basin on Wednesday. This storm is forecast to strongly split and weaken during the day Wednesday, with the southern portion diving into Arizona and the northern portion grazing our area through the day. We will get some cold air behind the storm, though the passage of the cold front is after the best moisture has left our area. With the uncertainties around a strongly splitting storm, I would expect total accumulations to be in the 2-5” range from early Wednesday through midnight when the snows should end.
Behind the storm, a ridge of high pressure builds over the West Coast ahead of strong storm forecast to develop south of the Aleutian Islands. Energy and moisture ejecting out of the storm and traveling over the top of the ridge may graze our area Thursday night and early Saturday morning, with light snow showers currently forecast for only Saturday morning. However, snowfall chances for either of these periods may change as the interplay between the ridge of high pressure and the incoming Pacific energy is difficult to forecast at this time.
But weather forecast models agree that a warm and dry ridge of high pressure moves over the West for most of next weekend. The fate of the Aleutian storm is contested by the models, with the European ECMWF moving toward the American GFS in predicting a split in the storm. However, whether the storm splits offshore or onshore will likely determine whether we see any weather associated with the storm during the following work week, and I hope to have more clarity on that by next weather narrative on Thursday afternoon.
Snowy upcoming week, except for Friday and Sunday
Wednesday, January 22, 2020
Snow showers have started up again this Wednesday afternoon in Steamboat Springs as a weak cool front in northwest flow approaches north-central Colorado. The briefly moderate snowfall intensity this afternoon will become lighter behind the front tonight and taper off during Thursday night. Most of Friday and Sunday look to be precipitation free with some light snow likely from Friday night into Saturday morning, but a couple of more storms forecast for later Monday and Wednesday will keep snows going for most of the upcoming week.
A ridge currently over the West Coast has directed moist northwest flow over the Rockies. A wave in this flow will bring a cool front through our area this afternoon, leading to breezy winds and generally light snow showers which could briefly become moderate. On top of this mornings report of 3.5” at mid-mountain and 4” up top, the snow report for Thursday morning should again be in the 2-5” range.
Though light snow could continue through Thursday night, warmer air aloft ahead of our next small storm for Friday night will stabilize the atmosphere and limit accumulations to 1-4” by Friday morning.
Though the daytime hours of Friday are likely to be precipitation-free, a weakening storm moves over our area from Friday evening through Saturday morning. I would expect total accumulations to be another 1-4” by noon on Saturday.
A ridge of high pressure then moves over the West during the weekend, allowing snows to cease from Saturday afternoon through Sunday night. But the break in the weather will be short-lived as another weakening storm moves over our area Monday followed by a better-looking storm for Wednesday. Light snow between the storms is currently advertised for Tuesday and again after the storm on Wednesday, making for a snowy upcoming week.
Some sort of ridge of high pressure is forecast to move over the West around the following weekend which should stop the snows and allow the sun to reappear for a time.
