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Snowpack Summary March 29, 2024
Posted by Allen Giernet @ 6:15 pm (this summary expires in 24 hours)
This summary applies to backcountry areas only.
The Bottom Line –
An Avalanche Watch will be in effect due the significant snowfall forecast for this weekend.
Travel in avalanche terrain is not advised at this time.
Storm Slab avalanches will become likely on all aspects above 7,500' Saturday. Wind Slab avalanches will become likely on Northerly aspects NE, N & NW with possible wind slab development on other aspects due to topographical influence. Moderate to strong Southwest to South winds are forecast into Sunday. Wind slabs will be found below ridges and on leeward sides of gullies. Forecast snowfall is significant with up to 24" above 8,000' by Saturday afternoon and possibly 3 - 4' at the higher elevations through Sunday. Any avalanches will have the potential to become large by entraining recent storm snow with the amounts of snow forecast. Look for signs of wind transport such as blowing snow, textured or pillowed snow surfaces and firm hollow sounding snow as signs of wind slab development. To reduce your exposure to these conditions look for wind sheltered terrain and choose lower angle slopes >30° for any travel. If the forecast snowfall totals do materialize the avalanche danger will increase through the weekend.
We are still operating on very limited on the ground data. If you are venturing out share any information you gather to [email protected] as our observation page has been malfunctioning.
Posted by Allen Giernet @ 6:15 pm (this summary expires in 24 hours)
This summary applies to backcountry areas only.
The Bottom Line –
An Avalanche Watch will be in effect due the significant snowfall forecast for this weekend.
Travel in avalanche terrain is not advised at this time.
Storm Slab avalanches will become likely on all aspects above 7,500' Saturday. Wind Slab avalanches will become likely on Northerly aspects NE, N & NW with possible wind slab development on other aspects due to topographical influence. Moderate to strong Southwest to South winds are forecast into Sunday. Wind slabs will be found below ridges and on leeward sides of gullies. Forecast snowfall is significant with up to 24" above 8,000' by Saturday afternoon and possibly 3 - 4' at the higher elevations through Sunday. Any avalanches will have the potential to become large by entraining recent storm snow with the amounts of snow forecast. Look for signs of wind transport such as blowing snow, textured or pillowed snow surfaces and firm hollow sounding snow as signs of wind slab development. To reduce your exposure to these conditions look for wind sheltered terrain and choose lower angle slopes >30° for any travel. If the forecast snowfall totals do materialize the avalanche danger will increase through the weekend.
We are still operating on very limited on the ground data. If you are venturing out share any information you gather to [email protected] as our observation page has been malfunctioning.
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
General discussion
A strong, cold winter like storm is forecast for this weekend. Snowline will be as low as 4,500' - 5,000' with up to 3" at this elevation. Above 8,000' 1-2' is possible and up to 4' at the higher elevations through the weekend. Moderate winds and heavy snowfall at times will combine to create dangerous avalanche conditions. Expect storm slabs to develop overnight and through Saturday with more snow accumulating Sunday. Storm Slabs will be likely above 7,000' especially where old snow exists. Moderate to strong Southwest to South winds will have plenty of snow to transport and could build large windslabs on leeward slopes. Look for the signs of wind transported snow near ridges and gullies. Wind scoured areas, sastrugi and textured surfaces, pillowed and smooth snow that is firm and hollow indicate wind slab formation. As we monitor the development of the storm we have issued an avalanche watch while we wait to see how the forecast materializes. Travel in avalanche terrain is not advised at this time. Avoid slopes over 30° and look for wind sheltered areas. Uncertainties exist regarding what condition the present snow surface is in, how well the new snow will bond to it and how much snow will actually fall compared to forecast totals. Carefully asses conditions where you are at and make decisions based upon what you see and the current information you have.
Please share any information when you are out in the mountains. Even a photo is helpful. Submit observations to [email protected] as our observation page is malfunctioning.
A strong, cold winter like storm is forecast for this weekend. Snowline will be as low as 4,500' - 5,000' with up to 3" at this elevation. Above 8,000' 1-2' is possible and up to 4' at the higher elevations through the weekend. Moderate winds and heavy snowfall at times will combine to create dangerous avalanche conditions. Expect storm slabs to develop overnight and through Saturday with more snow accumulating Sunday. Storm Slabs will be likely above 7,000' especially where old snow exists. Moderate to strong Southwest to South winds will have plenty of snow to transport and could build large windslabs on leeward slopes. Look for the signs of wind transported snow near ridges and gullies. Wind scoured areas, sastrugi and textured surfaces, pillowed and smooth snow that is firm and hollow indicate wind slab formation. As we monitor the development of the storm we have issued an avalanche watch while we wait to see how the forecast materializes. Travel in avalanche terrain is not advised at this time. Avoid slopes over 30° and look for wind sheltered areas. Uncertainties exist regarding what condition the present snow surface is in, how well the new snow will bond to it and how much snow will actually fall compared to forecast totals. Carefully asses conditions where you are at and make decisions based upon what you see and the current information you have.
Please share any information when you are out in the mountains. Even a photo is helpful. Submit observations to [email protected] as our observation page is malfunctioning.
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Disclaimer:
This Bulletin is designed to generally describe conditions where local variations always occur. Travelers are advised to exercise caution and make slope specific evaluations. As always, please treat this bulletin with appropriately guarded skepticism and make your own assessments. Help to provide more information to the community by reporting your observations
This Bulletin is designed to generally describe conditions where local variations always occur. Travelers are advised to exercise caution and make slope specific evaluations. As always, please treat this bulletin with appropriately guarded skepticism and make your own assessments. Help to provide more information to the community by reporting your observations
Latest Observtions
Click on the observation to go to the full report
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Observation type
Snowpack Location - Angeles Crest Date (yyyymmdd) -20230505 Comment May 5th, 2023.. Cinco De Mayo report on Angeles Crest.. NE aspect @ 8,000’ 15cm new snow Total snow depth. 195cm NE aspect @ 8500’ 20 cm new snow Total snow depth. 215cm N aspect @ 8800’ 35cm new snow Total snow depth. No bottom >280cm N aspect @ 9400’ 45-55cm new snow Total snow depth. No bottom >280cm Before 11-1200 snow was surprisingly light, dry but transitioning fast, and by 1400 it was rollerball and pinwheel city. Evidence of wet slides below 8k on east aspects affected by long hours in the sun. Temps were downright cold early, cool and mild mid day, but high May sun angle cooked the snow quick, and above 8k is now turned to hot pow and below 8k was lovely mank. |
Observation type -
Snowpack Location - Mt. Burnham - San Gabriels Date (yyyymmdd) - 20230423 Comment - April 22-23 2023 Long hauled 9 miles west of big pines for an overnight trip on the closed ACH. PCT hikers have just started to come through the area leaving somewhat of a worn path through still extremely deep avalanche run outs over the bench of ACH. The highway is still remarkably buried deep from BP to our destination 3 miles west of VG and beyond. Deepest is approx 25’+ under MB, which leads me to believe that we may not see ACH open until mid summer or not at all. The myriad of avalanche debris that are just now revealing themselves through the spring thaw is extensive and impressive. Above average temps and little to no refreeze below 9k yielded variable snow surfaces from hard fast firm to shin/knee penetration, even with ascension plates. Shallow glide cracks near and between steeper rock outcroppings were observed on some of the steeper north aspects approx 3-4’ deep. Wet loose instability was observed over the warm weekend will only small rider triggered slides no longer than the width of our boards on descent, and none of which ran further than 10-15’. There are still overhanging cornices that have yet to fail even under the late April sun angle and warm temps. Great corn to harvest when your descents are timed well. |
Observation type
Avalanche Location - Mt. Baldy Bowl Date (yyyymmdd) - 20230423 Comment - Wet loose debris noted toward skiers right of Baldy bowl. Another hiker told me he saw the avalanche happen around 6am. Fairly small and not destructive, but still something you wouldn’t want to be caught in. |
Observation type
Avalanche Location - Telegraph Peak Date (yyyymmdd) - 20230402 Comment - This wet slide occurred 4-11 afternoon @ 1:30 pm enroute to ski Telegraph peak. We had left the top of chair 3 and I was traversing towards The saddle of Telegraph peak when a significant crack occurred under my skis. I was able to maintain a traverse towards the trees and avoided getting caught! I thought it might be useful information if anyone is going to be skiing in the Telegraph peak area. |
General Caution
You should always use safe terrain management and carry avalanche rescue equipment in the backcountry. Most avalanches are triggered by someone in the party or the victim. Practice with your rescue gear often and be prepared should the worst happen. Though we do not have an avalanche forecast center in this area as of yet, the information posted and shared here as well as the resources available on this site will help to make informed decisions for your backcountry travels. Use avalanche forecasts in your travels wherever available and be aware that avalanche ratings are general information. Elevation, location, geographic variability’s, slope aspect and angle all have effects on the particular area you travel in. This is only one piece of the information you should use in your decision making process. There is no substitute for avalanche education, for more resources and information as well as education please refer to our resources page.
You should always use safe terrain management and carry avalanche rescue equipment in the backcountry. Most avalanches are triggered by someone in the party or the victim. Practice with your rescue gear often and be prepared should the worst happen. Though we do not have an avalanche forecast center in this area as of yet, the information posted and shared here as well as the resources available on this site will help to make informed decisions for your backcountry travels. Use avalanche forecasts in your travels wherever available and be aware that avalanche ratings are general information. Elevation, location, geographic variability’s, slope aspect and angle all have effects on the particular area you travel in. This is only one piece of the information you should use in your decision making process. There is no substitute for avalanche education, for more resources and information as well as education please refer to our resources page.
