Hoar frost

[Van Epps]

Has anyone been up above 5500' in the last 3 or 4 days? If so, how much build up of hoar was up there? Thinking of a Wednesday ride to chase the new snow but Im a little worried about the conditions.

thanks

BTW, here's why I'm itching!

Overnight: Snow showers likely. Mostly cloudy, with a low around 11. Wind chill values as low as -7. West wind around 17 mph, with gusts as high as 28 mph. Chance of precipitation is 60%. Total nighttime snow accumulation of 2 to 4 inches possible.

Monday: Snow likely, mainly before 10am. Mostly cloudy, with a high near 17. Wind chill values as low as -5. West wind 5 to 10 mph becoming south. Chance of precipitation is 60%. New snow accumulation of 3 to 5 inches possible.

Monday Night: Snow. Low around 17. South southeast wind around 10 mph. Chance of precipitation is 100%. New snow accumulation of 14 to 20 inches possible.

Tuesday: Snow. High near 20. West southwest wind between 9 and 11 mph. Chance of precipitation is 100%.

Tuesday Night: Snow. Low around 20. Southwest wind between 13 and 15 mph. Chance of precipitation is 90%.

 

[Hillboy]

stay in the flats

You will need to watch it with the avy danger.

 

[powder Head]

Please everyone be careful, I know we got dumped on, everyone got to ride, then we have had nothing for 3 weeks. We have a nice base, but it's a ball of ice, all this new snow we're going to get this week will be sitting on ice ready to slide. Please read the avy reports prior to riding and follow all of the safe practices. Don't sit in runout areas, travel single line a safe distance when crossing an avy path. Check the snow, and conditions throughout the day as they can change.

Have fun and be smart...........

 

[Adrenaline Revolution]

Please everyone be careful, I know we got dumped on, everyone got to ride, then we have had nothing for 3 weeks. We have a nice base, but it's a ball of ice, all this new snow we're going to get this week will be sitting on ice ready to slide. Please read the avy reports prior to riding and follow all of the safe practices. Don't sit in runout areas, travel single line a safe distance when crossing an avy path. Check the snow, and conditions throughout the day as they can change.

Have fun and be smart...........

speaking of which....

http://www.nwac.us/

 

[never_to_much_powder]

speaking of which....

http://www.nwac.us/

its HIGH for the next two days i was up in Ann yesterday i dont know to much about hoar but it was wind blown and crusty all over stay in the trees!!! and be safe

 

[CoyoteGirl]

Quoting powderhino from another thread:

Buried surface hoar is a problem now, and unless Mother Nature flushes it out during a natural cycle, it will remain a problem for a while.

Once it is covered, think of it as a gun that is cocked, and ready to fire. Sometimes it has a hair trigger, and doesn't take too much time of a load (YOU!) to set it off. Other times, it can stay "cocked" for a very long time, and people forget about it if they don't stay current with their avy reports.
We here in the Northwest don't "do" persistent weak layers well. We are not used to this sort of problem lingering in our snowpack. Well; it's here, and it is not going to disappear overnight unfortunately. Now we have to learn how to live with it.

How do you deal with buried surface hoar? With respect, and only go out armed with the latest avy center information to base your terrain choices on. It is okay to be conservative with your terrain choices now, in fact it is critical that you do. You can wait until the coast is clear before you head for the steeps, because as soon as this layer gets a significant load on it, it will become reactive. Stay on low-angle slopes that are not connected to steeper slopes above. Boondock the flats, or head for miserably thick tree's.

Watch the avy reports, choose conservative terrain until you are CERTAIN the hazard has flushed from the snowpack, and make sure your riding partners are armed with the same information you are, and you have all talked about it before you head out.

 

[2Thetopp]

Hoar frost Reply to Thread

Well put Brandy, we've all been itching to get out there however now's not the time to go climbing, good time to hone your boondocking skills and practice doing donuts in the meadows. We just finished an avy awareness class Saturday and this is the worst case scenario, prolonged ice conditions followed by a good dumping, not alot for that new snow to bond to, this is where the body count can go up fast like last year please us common sense and use what you've learned in class. Live to ride another day!

 

[White Rad]

talked with mt baker patrol over a beer in glacier last night and he said things were getting sketchy up there! as said above the obvious concern is well developed hoar layer being covered by all this new snow. freezing levels are supposed to rise towards the end of the week so we may get rain at some elevations to help bond the weak layer but NOT if it gets covered by 2-3ft first! so point is don't forget about this layer later in the season!! its like CO avy conditions with WA style accumulation...

 

[Van Epps]

Quoting powderhino from another thread:

Buried surface hoar is a problem now, and unless Mother Nature flushes it out during a natural cycle, it will remain a problem for a while.

Once it is covered, think of it as a gun that is cocked, and ready to fire. Sometimes it has a hair trigger, and doesn't take too much time of a load (YOU!) to set it off. Other times, it can stay "cocked" for a very long time, and people forget about it if they don't stay current with their avy reports.
We here in the Northwest don't "do" persistent weak layers well. We are not used to this sort of problem lingering in our snowpack. Well; it's here, and it is not going to disappear overnight unfortunately. Now we have to learn how to live with it.

How do you deal with buried surface hoar? With respect, and only go out armed with the latest avy center information to base your terrain choices on. It is okay to be conservative with your terrain choices now, in fact it is critical that you do. You can wait until the coast is clear before you head for the steeps, because as soon as this layer gets a significant load on it, it will become reactive. Stay on low-angle slopes that are not connected to steeper slopes above. Boondock the flats, or head for miserably thick tree's.

Watch the avy reports, choose conservative terrain until you are CERTAIN the hazard has flushed from the snowpack, and make sure your riding partners are armed with the same information you are, and you have all talked about it before you head out.

Thank you Rhino and CG. The Rhino (MJ?) is awesome. Met him (i think) at the Cle Elum Avy class over the week end. MJ is great!

talked with mt baker patrol over a beer in glacier last night and he said things were getting sketchy up there! as said above the obvious concern is well developed hoar layer being covered by all this new snow. freezing levels are supposed to rise towards the end of the week so we may get rain at some elevations to help bond the weak layer but NOT if it gets covered by 2-3ft first! so point is don't forget about this layer later in the season!! its like CO avy conditions with WA style accumulation...

This is what I'm nervous about. New over hoar, buried deep. What, if anything, will eliminate / bond a hoar layer once it's buried deep?

Thanks Modsldr!

 

[CoyoteGirl]

Thank you Rhino and CG. The Rhino (MJ?) is awesome. Met him (i think) at the Cle Elum Avy class over the week end. MJ is great!

Obviously I am biased, but I have to agree, MJ is awesome. His outreach to this community is something I've never seen before from ANY avalanche organization in my 9 years riding.

 

[newtrout]

Thank you Rhino and CG. The Rhino (MJ?) is awesome. Met him (i think) at the Cle Elum Avy class over the week end. MJ is great!




This is what I'm nervous about. New over hoar, buried deep. What, if anything, will eliminate / bond a hoar layer once it's buried deep?

Thanks Modsldr!

Not much, other than avalanche cycles and warming within the snowpack. That's why Canada fought deep slab avalanches all season long last year. They had a rain event early in the season. Similar effect to what we might be looking at.

Best we can hope for is some decent warming and a healthy natural avalanche cycle in the next couple days.

 

[Hillboy]

RAIN will both destabilize but also create bonding in the snow pack in condition with heavy Hoar frost. Metamorphisis of faceted crystals is excelerated by the very cold temps. All that said the snow level rising significantly will allow the snow to cycle and bond just stay the hell out of the hills when the rain begins and go back when we get new snow on a solid pack.

Hill headed to Mexico for 2 weeks OUT

 

[Powderhino]

Thank you Rhino and CG. The Rhino (MJ?) is awesome. Met him (i think) at the Cle Elum Avy class over the week end. MJ is great!




This is what I'm nervous about. New over hoar, buried deep. What, if anything, will eliminate / bond a hoar layer once it's buried deep?

Thanks Modsldr!

Surface Hoar, once buried, is a sneaky bugger. It can persist for very long periods of time (months). Once buried, rain percolating through the snowpack will destroy the chrystalline structure of surface hoar and bring it back into line. Bridging, a non-technical term that basically means enough snow falls to "cap" the layer and can give a false sense of security. If you see the fx's and they mention "bridging", think of bridging as easy credit: you can get away with buying a little riding now, but sooner or later, you are going to pay. The weak layer hasn't gone away, it is just dormant until a big enough trigger (a group of riders...) breaks through and triggers a slide.

My advice? Stay away from easy credit, pay as you go, and be satisfied with what you can afford NOW, because now is what really matters. You can ride the steeps later when there is no hazard....

 

[Kordero]

Also anyone ever here of Whumphing? It is an indicator of "Bridging" as MJ points out and also from wind-slabs.

Whumphing is caused by failure somewhere in the snowpack and is NOT GOOD. OK, actually it is good if you recognize it. Means BEWARE!!

 

[White Rad]

times like these i do miss the wide open parks in CO, hard to find "safe terrain" around here. Here is what NWAC says this morning...

"Early field observations Tuesday morning indicate widespread and very sensitive avalanche releases from control results at Mt Baker, Crystal Mountain and Mt Hood Meadows. In those areas, widespread propagation was seen with most paths running full width with 12 to 18 inches slab depths most common. Slides were mostly running on the weak snow layers just above the crust. Mt Hood had received the greatest new snow amounts and had pockets of wind slabs of 2.5-3 ft."

 

[Van Epps]

widespread propagation was seen with most paths running full width with 12 to 18 inches slab depths

Think about that!!!! Sobering


Seems the wise thing is to play it safe......... we are doing so even though half of me is screaming to get up high..... the other half recognizes the dangers present. Guess I'm growing up cause we're playing it safe tomorrow. Going to rip up the trees!!

Hope everyone stays safe and has FUN!!