Snowpack Summary April 18, 2023 End of Season
Posted by Allen Giernet @ 7:30 am (this summary expires in November 2023)
This summary applies to backcountry areas only.
The Bottom Line –
This is the last snowpack summary of the season. Although avalanche danger is generally low, avalanches will still be possible. Our biggest concerns will be warming and solar input during the days increasing the chance for wet loose avalanches each day. Fast firm conditions will be possible in the early morning hours especially following below freezing overnight temperatures. Have the experience and skill to evaluate avalanche danger and match your terrain and travel choices to conditions and your skill level. Use weather forecasts and your observations of recent avalanches, roller balls and firm snow becoming soft sinking into boot top depth. this information will inform your decisions and if your uncertain remain in lower angle terrain below 30°.
Weather links on the site are always active for you to monitor conditions in the area you plan to visit. We will continue to monitor weather and conditions through the spring.
Observations will continue to be updated, use this resource and please submit your observations to the Avalanche Center.
Please share your observations with us at the avalanche center Submit Reports page.
Posted by Allen Giernet @ 7:30 am (this summary expires in November 2023)
This summary applies to backcountry areas only.
The Bottom Line –
This is the last snowpack summary of the season. Although avalanche danger is generally low, avalanches will still be possible. Our biggest concerns will be warming and solar input during the days increasing the chance for wet loose avalanches each day. Fast firm conditions will be possible in the early morning hours especially following below freezing overnight temperatures. Have the experience and skill to evaluate avalanche danger and match your terrain and travel choices to conditions and your skill level. Use weather forecasts and your observations of recent avalanches, roller balls and firm snow becoming soft sinking into boot top depth. this information will inform your decisions and if your uncertain remain in lower angle terrain below 30°.
Weather links on the site are always active for you to monitor conditions in the area you plan to visit. We will continue to monitor weather and conditions through the spring.
Observations will continue to be updated, use this resource and please submit your observations to the Avalanche Center.
Please share your observations with us at the avalanche center Submit Reports page.
General Springtime Concerns
Wet Loose – Significant warming and little to no overnight freezes will increase the chance of Wet Loose instability. Start early and finish early while avoiding solar effected slopes. Watch for signs of wet snow as you travel and the day warms. Starting on firm snow that gives way to sinking to boot top depth is a sign of wet loose instability. Look for roller balls and pinwheels emanating from rock outcroppings and move to lower angel terrain and less solar affected aspects if you see these signs. Wet Loose avalanches will not generally bury you but can knock you off your feet and carry you through or over nasty terrain features with cataclysmic results. Be aware what is below you and rapidly changing snow conditions.
Fast Firm conditions – is possible on all aspects especially at upper elevations following below freezing overnight temperatures. These conditions will pose the risk of slide for life scenarios until slopes are softened by temperature and sun. This hazard is the most prominent cause for rescues in our local mountains especially areas such as the Baldy Bowl. A slip and fall can result in an uncontrollable slide with potential catastrophic results. Be sure to bring proper equipment (ice axe & crampons) with the skills to use them before committing to steep firm slopes. Be aware of snow surfaces you are traveling and changes as you move through different aspects and elevations as well as what is below you. Change terrain if these conditions develop before you find yourself in a situation you can’t retreat from.
Cornice Fall – Rapid warming and little to no overnight freezing can destabilize these features. Give cornices a generous margin as they break off farther back then expected. Stay out from under cornices as temperatures rise They can break off with no warning and are hard to predict.
Exercise caution if venturing out into the mountains and use avalanche protocols, travel with a partner and bring your beacon, shovel and probe.
Please share any information when you are out in the mountains. Even a photo is helpful. Submit observations to Submit Reports page.
Wet Loose – Significant warming and little to no overnight freezes will increase the chance of Wet Loose instability. Start early and finish early while avoiding solar effected slopes. Watch for signs of wet snow as you travel and the day warms. Starting on firm snow that gives way to sinking to boot top depth is a sign of wet loose instability. Look for roller balls and pinwheels emanating from rock outcroppings and move to lower angel terrain and less solar affected aspects if you see these signs. Wet Loose avalanches will not generally bury you but can knock you off your feet and carry you through or over nasty terrain features with cataclysmic results. Be aware what is below you and rapidly changing snow conditions.
Fast Firm conditions – is possible on all aspects especially at upper elevations following below freezing overnight temperatures. These conditions will pose the risk of slide for life scenarios until slopes are softened by temperature and sun. This hazard is the most prominent cause for rescues in our local mountains especially areas such as the Baldy Bowl. A slip and fall can result in an uncontrollable slide with potential catastrophic results. Be sure to bring proper equipment (ice axe & crampons) with the skills to use them before committing to steep firm slopes. Be aware of snow surfaces you are traveling and changes as you move through different aspects and elevations as well as what is below you. Change terrain if these conditions develop before you find yourself in a situation you can’t retreat from.
Cornice Fall – Rapid warming and little to no overnight freezing can destabilize these features. Give cornices a generous margin as they break off farther back then expected. Stay out from under cornices as temperatures rise They can break off with no warning and are hard to predict.
Exercise caution if venturing out into the mountains and use avalanche protocols, travel with a partner and bring your beacon, shovel and probe.
Please share any information when you are out in the mountains. Even a photo is helpful. Submit observations to Submit Reports page.
General Mountain Weather Forecast |
Weather Page Link
Click on the links below for the latest information
Click here for this Season's Snow Pack Summaries
To better understand the challenges and potential variability over the large area we are producing information for please read our Snowpack Summary - Format and Limitations
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
Observation type
Snowpack Location - Malt Diablo Date (yyyymmdd) -20230409 Comment Toured up Alto Diablo from the South Fork trailhead. Spotty coverage at the trailhead became skinable by Horse Meadows, but with the warm temps the exposed flats were thinning quickly. However the snowpack is deep and continuous on the north slope itself. Skinning conditions were excellent, though the snow was still in the early phases of transitioning to spring and not proper corn yet. This made the descent somewhat challenging with in the deep, heavy transitioning snow, but still an enjoyable day in the mountains. Near the bottom of the face we did observe evidence of small recent loose-wet activity originating from a rock outcropping, which appeared to incorporate a few inches of looser unconsolidated snow sliding on a thin melt-freeze crust. |
Observation type -
Snowpack Location - Pine Mtn. Date (yyyymmdd) - 20230408 Comment - April 8th, 2023 Firm icy conditions early yielded to almost corn conditions as temps rose… We climbed acorn canyon above WW in dawn hours to destination pine mtn. Morning had us traveling on firm icy conditions where crampons and ice axe were needed. North and West aspects were bulletproof so at 10 am we dropped an east aspect along north backbone under pine mountain. Drop at approx 8800’ and rode down to 7700’. Snow had the look of corn but wasn’t quite corn yet as we found most of the snow we were to ride was in transition still. We climbed on and later summited. Dropped north gully and found some colder and drier snow up high near summit that was nice to ride, but soon found slower old hot powder below that was fun but laboring. Around 16:30 we were on top of acorn canyon and dropped north aspect where we careful not to set off several wet loose slides that weren’t necessarily large but concerning given the consistency. Fun day, but snow is still transitioning. Keep your head on a swivel. |
Observation type
Snowpack Location - Alta Diablo Date (yyyymmdd) - 20230406 Comment - Toured up Alto Diablo to ski the lower NE facing cirque. Slopes NW through NE held good supportable spring snow all day with varying quality depending on time of day. Sheltered, steep, true north facing slopes were still cold pow. Several E facing slopes had cycled on top of a pretty greasy bed surface. WL snow I presume from the most recent storm. We observed one natural that almost made it to the flats below the N ridge. Nothing that would bury you but definitely knock you over! Around 4:30pm we traversed through an east facing slope. Snow was refrozen but noticeably unsupportable. |
Observation type
Avalanche Location - Wrightwood Date (yyyymmdd) - 20230402 Comment - Skied from Galena Peak with partner J.T. We were on the lookout for loose/wet slides and avoided exposing ourselves to large consequential lines. On our exit we witnessed this D1/R2? wet/loose slide. It began from a small point about 1/3 down the line, below a rock face being warmed in the sun. |
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.