Next big storm starts on Sunday
Thursday, February 13, 2020
It was snowing this Thursday morning in Steamboat Springs, and with the 7” of snow currently showing on the Powdercam at the top of Sunshine Peak added to the 5” yesterday, the upper mountain has received around a foot of very light and fluffy snow. The phone report this morning disappointingly omitted the base measurements today, which is odd as I expect that we hit the century mark up top for the first time this season.
As discussed in the the last weather narrative on Sunday, this storm ended up tracking much further west than the weather forecast models had earlier indicated, which is not unusual when there is a giant pool of cold air to our northeast that is accessible to mix with storms from the northwest.
There may be additional showers this afternoon in the cold, moist and unstable northwest flow behind the storm, with another 1-4” possible before we dry out on Friday and see the sun return.
Another storm grazes our area on Friday night into Saturday morning, though this one is currently trending weaker than earlier forecast. While there is some cold air associated with the storm, and we may see some showers as the storm passes by through early Saturday, we may see some sun again by the afternoon as the inconsequential storm moves to our east.
But the break in the weather will be short-lived as a good-looking storm begins snow in our area on Sunday. While weather forecast models agree on significant precipitation, the disagree on the timing and length of the storm, with the European ECMWF currently bringing the greatest impacts during the day Sunday and the American GFS starting higher intensity snows later in the day Sunday and continuing them into the Washington’s Birthday holiday.
Most of the uncertainty is due to the storm possibly splitting as it crosses the Pacific Northwest coast on Sunday. The ECMWF keeps the storm mostly moving which means earlier snows with less duration. The GFS, on the other hand, forecasts a significant split in the storm, slowing its eastward movement and stalling the cold front over our area from Sunday night through part of Monday.
Either solution or a compromise is possible at this point, with a rough guess of a foot if the ECMWF verifies and possibly twice that if the GFS is right. I may push my regularly scheduled Sunday weather narrative to Saturday if there is more agreement in the weather forecast models by then.
Regardless, they both concur more cold air will follow the storm and persist through at least midweek. But the weather beyond midweek is very uncertain, and is dependent upon how much the storm ends up splitting earlier in the week. The more aggressive GFS, with its stronger split, has the southern end of the split forming a warm storm that moves over our area later in the work week, while the ECMWF has cooler and more showery weather for that time frame. Stay tuned for my next forecast on Saturday or Sunday for more details.
Unsettled weather for the upcoming week
Saturday, February 8, 2020
Sunny skies and warm temperatures are gracing the Steamboat Springs area early this Saturday afternoon as the town digs out of the impressive departing storm. The two day total ending at 5 am Saturday morning at mid-mountain at the Steamboat Ski Area was 22.5”, with almost of that falling between Wednesday and Friday nights. Tuesday and Friday currently look like the driest days of the upcoming week with cool temperatures and chances for some snow each of the remaining days.
I am pushing this weather narrative out a day early because I wanted to talk about the previous storm and note that there will be a cold front moving through our area during the Winter Carnival festivities at Howelesen Hill tonight, where there may be a world record firework attempt.
The storm delivered as advertised, though snow quality suffered due to a dense layer of snow that fell between 5 pm and 9 pm on Thursday evening. The 8.5” I measured on my deck at 5 pm was light and fluffy, and I observed some graupel falling around then, which looked like the round “Dipping Dots” frozen treat. By 9 pm, the additional 4” on my deck was much denser than what fell before it, and I believe this layer of snow fell over the whole mountain. Distressingly, there was also a layer of ice on the grab rails at the loading areas of the Sundown and Elkhead lifts first thing Friday morning which indicated an earlier period of freezing precipitation that likely fell on top of the dense layer of snow. While it was snowing heavily that morning, with snowfall rates approaching 3” per hour at times, the denser layer in between the Thursday daytime snowfall and Friday morning snowfall made for some inconsistent skiing.
But the sun is out now in advance of a cold front expected to pass through our area this evening, courtesy of the northern part of a splitting storm currently affecting the Pacific Northwest. Even the short-range weather forecast models are struggling with the forecast snow amounts, with snows, if they occur, starting after sunset and peaking around mid-evening before ending within a few hours after midnight. But the latest models have backed off snow amounts for our area in favor of areas to our south, making for an uncertain forecast. It’s likely we will see some snow around and behind the front, with briefly high snowfall rates of an inch per hour or more at times this evening, and at this point I would guess 2-5” which would be reported Sunday morning.
The cold front looks to stall south of our area as the main part of the split storm moves southward along the California Coast on Sunday. But energy ejecting out of the California part of the storm will overrun the front and keep the possibility of light snows for our area for Sunday and Monday.
Meanwhile, a wave of Pacific energy rounds the persistent ridge of high pressure in the eastern Pacific on Sunday. Not only with this bring another cold front through our area around Monday night, but it will also force the California storm eastward, with the two storms merging near the Four Corners on Tuesday. Most of the precipitation will be to our south, but light snow for our area will be possible for early Tuesday morning, along with cool temperatures, before the weather clears for most of the day Tuesday and some of Wednesday.
But hard to predict waves of Pacific energy are forecast to round the still-present ridge of high pressure in the eastern Pacific and graze our area later Wednesday and Thursday. These waves may end up too far east to give us much weather, or move further west giving us much better chances for snow, and at this time the outcome is uncertain.
It does appear that there will be a break in the unsettled weather for at least part of Friday before another storm may approach our area for the beginning of next weekend. I should have more details on the weekend storm by my next regularly scheduled weather narrative on Thursday afternoon, though I may push that to Wednesday if weather models trend stronger with the possible storms.
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.