Wednesday, December 13, 2017

Upper Mountain Conditions December 13

Here is a quick note on conditions. As calendar winter approaches people may be considering a winter attempt of the summit. A ranger went up to Camp Muir today to have a look at condition on the upper mountain.

We have had unseasonably nice weather recently and this has not done the mountain much good in terms of climbing conditions. The rain event that started on Thanksgiving was warm enough to have that rain go all the way to the summit. This produced a think ice crust all over the volcano. A few storms coated the mountain with more snow and covered the ice but the recent high pressure and windy conditions have scoured the snow off the steeper slopes. That has resulted in large patches of exposed blue ice over much of the upper mountain.

Some photos from the Muir Snowfield and Camp Muir.


There are visible ice patches on Gibraltar Ledges and at the top of Gib Chute.


The Cowlitz Headwall with exposed ice all over.
So for now the upper mountain would be extremely difficult and hazardous to climb. Even moving around Camp Muir requires crampons. The weather pattern is shifting though and we expect more snow to start arriving on Friday.

Wednesday, December 06, 2017

Avalanches in Moderate Hazard

An avalanche was reported to have been triggered by two unidentified snowboarders on December 5th. The avalanche was large and could have easily buried and killed one or both of the parties. The avalanche occurred on a west-facing slope near treeline on Panorama Point. This area is easy to reach from the Paradise parking lot and is frequented by backcountry skiers, snowboarders and snowshoers.

One of the snowboarders was witnessed to have been swept into the avalanche and was deposited on the surface of the debris. The other snowboarder was not caught by the avalanche. Thankfully both parties were, apparently, uninjured and were able to self-rescue.

By the time rangers visited the site the following morning the avalanche path was reloaded with fresh wind slab and the debris pile was mostly covered with wind deposited snow.



The Avalanche Forecast that was issued for December 5th came out at 6:00 PM on Monday, December 4th. The Avalanche Hazard was listed as:
  • MODERATE Above Tree Line
  • MODERATE Near Treeline
  • LOW Below Tree Line
That may sound like a fairly benign hazard to many people, so how is it that a large sized avalanche was triggered on a day such as this?

The first thing to consider is that approximately 30% of avalanche fatalities occur on a day where the hazard is listed as Moderate. If you look at the definition of Moderate Hazard in the North American Danger Scale what you'll read is this:



It states that heightened awareness is necessary and there is the possibility of large avalanches in isolated areas and that it will be possible for humans to trigger them. So how could this slope have been avoided using the forecast? Let's take a look at what was said.

The very first thing written was:

The Bottom Line: There is less confidence in the forecast above treeline, due to limited observations. Travel with more caution if venturing to higher terrain due to recent heavy storm cycle loading through Saturday where wind and storm slabs may need more time to heal.

So already we know that large avalanches are possible and that more caution is needed when travelling in 'higher terrain'. If you were planning to venture above treeline in Mount Rainier National Park that would qualify as higher terrain.

If we look at the Detailed Forecast there were two very pertinent lines.

Fair weather with gradual warming is expected Tuesday with gradually increasing easterly crest level winds.
Watch for areas of wind transport and fresh wind slab deposits if easterly winds increase above forecasted. 
Now we know that we will need to watch out for areas where wind, from the east, will deposit snow especially at higher elevations and near ridge tops and that we should be even more cautious if the winds increase more than expected.

In hindsight we can see that the 'incresing easterly' winds deposited 'fresh wind slab' onto the west-facing slopes on Panorama Point right at treeline and so this isolated terrain feature was primed for a large sized avalanche. Unfortunately someone ventured onto that loaded slope and triggered an avalanche. Fortunately they were able to escape injury or worse.

This close-call can serve as a lesson for everyone and a reminder that Moderate Hazard still requires cautious decision making and appropriate terrain choices.

Saturday, November 18, 2017

Sunshine before the Storm

The sun finally broke through the clouds and Paradise felt almost like a beach today!  The upper parking lot filled up during the day with skiers, snowshoers,  photographers, and even some people just up for a picnic in a winter wonderland.  There were views aplenty of the upper mountain.  Calm winds and a warming air temperature trend made it hard to believe Thanksgiving is next week. 

Snow conditions varied with both aspect and time of day.  Wind from the last storm cycle came primarily from the southwest leaving wind packed and firmer conditions and about 3 inches of ski penetration.  The leeward northeast aspects had softer drifts and more variable, but deeper ski penetration.  Solar radiation started making noticeable changes midday, changing the fluffy drifts into mashed potatoes.

The forecast doesn't look good for skiers, the Mount Rainier Recreational Forecast says:

WINTER STORM WATCH IN EFFECT FROM SUNDAY AFTERNOON THROUGH
LATE SUNDAY NIGHT: 
Weak high pressure will give way to a vigorous front on Sunday 
afternoon and evening. 
SUNDAY...Windy. Mostly cloudy in the morning, then rain and snow
in the afternoon. Snow accumulation near Paradise up to 3 inches.
Snow level near 4000 feet. 
SUNDAY NIGHT...Windy. Rain and snow. Snow accumulation near 
Paradise of 4 to 8 inches. Snow level near 5000 feet. 
 
Extra caution should be used when recreating in the backcountry as a storm front like this approaches the mountain.  Simple equipment failures, navigation errors, and small injuries can lead to serious consequences when the weather turns for the worse.  Please remember that there's no ski patrol on Mount Rainier.  Rangers and Search & Rescue Volunteers are at least hours, and possibly days(!), away from reaching injured and lost parties and storms can prevent any search or rescue attempt.

Almost five feet of snow has accumulated in the Paradise area.  This is a great start for our base snowpack.  There's still some small trees and rocks sticking out, and creek drainages shouldn't be entered, but many of the smaller hazards are buried until spring.   

Check the Park's Twitter Feed for the latest on the road condition and closures and come on up for a visit!  Be safe out there and have a happy Thanksgiving!

Tuesday, November 07, 2017

Chinook and Cayuse Closed for Winter

Chinook Pass and Cayuse Pass on the east side of Mount Rainier have been closed for the winter season.  WADOT and the NPS consider the snowpack, the avalanche danger, and the weather forecast when making the decision to close the highways for the season, and it typically happens in mid-November.

Check out the park's road status webpage for more details. 

It's also getting to be the time of year when the road to Paradise is closed at night for snow removal operations.  The park's twitter feed is the best way to track when the Paradise Road will be open on a daily basis. 

Saturday, November 04, 2017

Winter is Back!



On November 3 Longmire received it's first recorded snow for the 2017/2018 winter season and it looks like there's a lot more on the way. The UW GFS model shows anothher good hit of snow coming our way with significant accumulation.
Of course Paradise received considerably more snow than Longmire did and this is welcome news for skiers and boarders. We want to make sure that folks are taking precautions with all of the new snow we are expecting. The Northwest Avalanche Center has not yet begun issuing a daily forecast yet but it has issued a statement for the weekend. The one that pertains to the Paradise area can be found here.
Reading through it will give you an idea of what to expect if you're planning to travel above treeline, especially this:
Given the recent heavy snowfall in parts of our forecast zones, expect the potential for avalanches at higher elevations as conditions for storm slab and loose dry avalanches (primarily) will be present this weekend where anchoring is insufficient.

For more reading about early season avalanche hazard check out this short paper by Avalanche Canada.

Have fun out there but please be safe!

Saturday, October 28, 2017

Muir Snowfield and Summer Conditions in October

Low snow conditions still exist on Mount Rainier.

After a few good punches of cold precipitation skiers have begun spooling up for winter. The parking lot at Paradise has been filling up earlier and there's a lot more cars with ski racks and cargo boxes. Tales of skiing from Camp Muir all the way to Paradise have also been popping up online.

At the tail end of the big snow dumps we experienced a pretty good atmospheric river event with lots of wind as well as a lot of really warm precipitation. That event looks like it triggered a decent avalanche cycle from approximately 7,500' to 8,500'. The evidence that there was instability in the snowpack should serve to caution the early season go-getter's. It's not the worst idea to start your season out nice and slow and keep the terrain choices conservative.


A large crown and avalanche debris on Wapowety Cleaver.


The cycle has subsided now and in the past few days the sun has come out and temps have turned unseasonably warm. This has resulted in some nice corn skiing conditions on the Muir Snowfield. Today (Saturday, October 28) a ranger counted 72 skiers on the snowfield along with several hikers and snowshoers all taking advantage of the nice weather.

There is patchy snow from just above Paradise but the continuous snow does not start until above Pebble Creek (7,200') and so walking up and down from there is pretty much mandatory. This makes your footwear strategy hard to figure out. Running shoes or light hikers would be great to carry up but the trail is muddy, full of puddles and the snow patches are slushy. Low top shoes will get soaked. Hiking or climbing boots will keep your feet drier, of course they're heavy. The last option is to just walk in your ski boots but that is really tough on the feet and can put a lot of wear and tear on the gear. All three techniques were in full display on Saturday.

Above Pebble Creek the snowfield is fairly smooth with just a little wind effect here and there. The best skiing is between 10,000' and 8,000' with the lower stuff not freezing well overnight and staying slushy. The road will be open 24 hours a day until the next round of storms forces us to shut it down so take advantage of the ability to get an early start. It's probably best to start your descent before 1:00 PM to get good snow conditions. The late afternoon snow could be pretty tough to ski/board on.

Ski tracks in soft snow lead to the toe of the Muir Snowfield.

Just a note on climbing and skiing on the glaciers. With a light coating of snow and freezing levels at 14,500' this might be the most dangerous time of year to attempt to go for the summit or even get out on the lower glaciers. The crevasses that were wide open and obvious in September are now thinly veiled with a cover of slush and anyone choosing to climb or ski out on them is taking on a high degree of risk. It's a better idea to get your ski legs in shape on the mellower, non-glaciated slopes and let the mountain recharge with lots more new snow.

A snowboarder on the Muir Snowfield with the Nisqually Glacier in the background.

Have fun and be safe!

The Mount Rainier Climbing Rangers