Colorado Daily Snow
By Joel Gratz, Founding Meteorologist Posted 6 years ago May 16, 2017
Powder days May 18-19 … seriously! (UPDATED: Fri, May 19)
Update
UPDATE: Fri, May 19th
- Abasin reported 9 inches on Thursday morning and another 12 inches on Friday morning for a total of 21 inches. Woohoo!
- The highest reports (http://www.weather.gov/source/crh/snowmap.html?zoom=10&lat=40.06&lon=-105.37&hr=48) have been 30-38 inches in the foothills west of Boulder.
- SNOTEL stations in Rocky Mountain also show accumulation around 30-36 inches with 2-3 inches of liquid water equivalent.
- It is still snowing along the divide from about I-70 north to Wyoming.
- Have fun in the snow and be mindful of the avalanche risk as 20-40 inches of new snow in 36 hours is a lot of weight.
- Also, completely not snow related, I was invited to participate
Thanks for reading!
JOEL GRATZ
UPDATE: Wed, May 18th
- The storm is here and will last through Friday.
- The storm is bringing in LOTS of moisture. Since moisture is the fuel for snow, this sets the stage for big-time snow amounts.
- Most mountains across Colorado have measured 8-12 inches between Wednesday afternoon and Thursday morning.
- Abasin is the only mountain spinning lifts, and they reported 9 inches on Wednesday night and another 3 inches has fallen on Thursday morning between
- The deepest snow I have seen so far is at Copper where their snow stake shows 20+ inches between Wednesday evening and Thursday at
- I-70 is shut down in both directions for much of the stretch between Vail and Denver due to the heavy snow and multiple crashes.
- Many mountains have shut off their webcams, so it’s hard for me to see how much snow has fallen elsewhere. Most SNOTEL stations (automated backcountry weather stations) show about 8-12 inches (+/-) for many mountains.
- Because of the abundant moisture in the air, and because this storm will move slowly and will bring snow for at least another 24-36 hours (through Friday evening), snowfall totals could be VERY deep.
- The deepest totals will likely be near and east of the divide from about I-70 north to Wyoming. Amounts in this area could be 30-50 inches by the end of the storm.
- At Abasin, like I mentioned, storm totals could be 20-30 inches. My previous forecast was conservative and this storm is over-performing due to its slow movement and abundant moisture. The powder should be amazing but you’ll have a tough time getting there if you aren’t already in Summit County.
- For the rest of the state, most mountains should measure 10-20 inches, but as we saw with Copper, amounts could be 1.5x to 2.0x higher if heavier bands luckily track over a certain mountain.
- This storm is fantastic not just because of powder but because of the
- Have fun in the pow and be safe from falling trees (that are heavy with snow on leaves), shoveling heavy snow, and from avalanches which will be a very real threat with the amount of new snow.
JOEL GRATZ
UPDATE: Wed, May 17th
- Thursday and Friday look like powder days
- Abasin should get 10-15 inches with the deepest powder on Thursday and Friday
- Areas along the front range mountains, north of I-70 to the Wyoming border, could receive 15-40 inches (seriously). See the map below.
- Boulder climatologist Dr. Klaus Wolter provided a historical reference for this storm: "For reference, the biggest May snowstorm I could find for Boulder was 19" of snow
- Based on these numbers, it's possible that this storm could be record-breaking for elevations above about 7,000 feet in the northern front range.
- Areas below 7,000 feet near Denver will see snow flakes. Snow accumulation will vary greatly based on a difference of a few degrees in temperature. Snow will mostly accumulate on non-paved surfaces. There could be lots of tree damage.
- Have fun in the (deep) pow on Thursday and Friday. There could be enough snow for serious avalanche concerns, so don't let your guard down in the backcountry.
- Last thought - yay for pow!!!
UPDATE: Tue, May 16th
Yes, it’s true, most of Colorado’s mountains and some of the lowlands will get snow later this week. It’s not crazy that snow is falling in May, but the amount of snow that’s possible is a bit unusual. How about 1-2 FEET in the mountains!
On Wednesday, all mountains will see snow showers and cooler temperatures.
Then from Wednesday afternoon through Friday afternoon, the coldest air will move over Colorado and snow will fall most of the time over the northern mountains.
Here is the forecast radar from Wednesday afternoon through Thursday midday covering Colorado. You can see how the showers turn into steady snow over the northern mountains.
Timing – the heaviest snow should fall from Wednesday night through Thursday evening.
Snow level – I think we’ll see flakes all the way down to 5,000-6,000 feet. This means that areas around Denver will see flakes on Thursday, though with the high sun angle of May most of the roads at lower elevations will be wet. The worst impacts in the lower elevations will likely be the weight of the snow on trees. Above about 6,500 - 7,000 feet, snow should accumulate on the grass and roadways.
Powder – Abasin is the only mountain that is still spinning lifts, and I think you’ll find legitimate powder on Thursday all day and Friday morning.
Below is the snow forecast for Abasin from the European model. The green bars show the average snow forecast of 14 inches from 51 versions of the model. That’s an exciting forecast!
Keep your snow tires on if you’re planning to ski pow on Thursday and Friday. The mountain roads will be snow-packed, temperatures will be in the 20s, and it’ll feel like winter. Hurray for more precipitation and especially hurray because a lot of this precipitation will fall as pow!
OpenSummit
If you’re planning to hike/ski any of Colorado’s 14,000-foot mountains this spring, summer, and fall, we made an app just for you!
Find hourly forecasts for lightning (the biggest danger), precipitation, temperature, and
INO Weather Pro
This is a new lightning detection device that is being offered to outdoor folks like ourselves as well as folks that run sporting events and construction sites.
It provides the number and distance of lightning strikes out to 40 miles, temperature, humidity, and altitude WITHOUT A CELL SIGNAL.
The fact that this portable weather station measures lightning activity without a cell signal is important (because we usually do NOT have a signal when in the remote mountains). Right now, there are many mobile apps that provide lightning data, but all require an internet connection.
I tested this device and while I found that it mostly worked as promised, at a list price of $497, I don’t know that the value is there for someone occasionally hiking in the mountains.
While the device does detect lightning up to 40 miles away, it won’t necessarily tell you whether a storm is approaching your exact location. So you might find yourself hiking, getting a message from the device that there is lightning between 20-40 miles away, and then you might be at a loss of what to do. Is the storm moving closer and should I seek shelter immediately? Is the storm not moving toward you at all?
If you do see additional strikes that are closer to you, it would be a reasonable assumption that the storm was moving toward you. But also, when strikes are within about 10 miles, you will be able to hear thunder, and that’s a pretty good (free) indicator that you should seek a safe location.
I wanted to love this device because anything that can keep myself and my friends safe when outside is a great investment. But at $497 and with lightning data binned into big buckets like “8-20 miles away”, I’m not sure that the features justify the price. Also, the attitude feature uses barometric pressure and not GPS, so the altitude reading will usually not be accurate since it will vary along with the weather patterns.
It’s great to see people working on new devices to keep us informed about lightning, but I don’t know that this device is worth the investment for most people.
You can find out more about the INO Weather Pro here.
I am giving a talk at Telluride Mountainfilm
Telluride is an amazing town, and it should be gorgeous during the last weekend of May with snow-capped peaks and a green, warm valley. There are a LOT of amazing films, talks, and events going on between May 26-29.
I am thrilled to be on a panel on Sunday, May 28 titled “The Future of Skiing”. I will give a short presentation on temperature trends here in Colorado, and then will have a discussion with professional skiers Jeremy Jones and Angel Collinson, Telluride Ski Resort CEO Bill Jensen, and Aspen Skiing Company VP of Sustainability (and excellent author) Auden Schendler.
More here: https://www.mountainfilm.org/festival/schedule/blocks/sheridan-opera-house-sunday-915-am
Colorado Public Lands Day on May 20th
Whether you ski, hike, bike, snowmobile, hunt, fish, or engage in other fun and mayhem in the Colorado outdoors, chances are that a lot of this activity occurs on public lands. Celebrate these lands with events and contests on May 20th.
More here: http://copubliclandsday.com/
Next Update?
I will update THIS post (not a new post) during the snow storm if the forecast changes. After the storm, I will likely NOT write another post until later in the summer, but who knows … if we get another big storm, I’ll be back:-)
Thanks so much for reading the Colorado Daily Snow!
JOEL GRATZ