SPRINGTIME AVALANCHE TIPS – Timing is everything
Watch for the “shed cycle”. One great way (and an old timer rule of thumb) is to keep an eye on the ridgetop weather stations. Avalanche activity often follows multiple consecutive days (usually 3) of above freezing overnight temperatures. This can signal a snowpack with limited refreezing and when followed by warm days (either sunny or rainy) dramatically increases the likelihood of natural and human triggered large wet avalanches. Careful route planning to stay out from under slopes with wet and rotten snow is essential during this period. See below for some additional general springtime tips:
SEASON WEATHER ROUNDUP
Check out our Weather History page where you can find our monthly weather charts. Here is the weather chart for April.
SNOWFALL and SNOW DEPTH – (Turnagain Pass SNOTEL 1,880ft on Center Ridge)
Seasonal snowfall was 322“ (Nov 1 – Apr 30) – in a feast or famine regime. Last season snowfall was 385″ for comparison. In fact, of the 322″ of snow that fell on Turnagain Pass, 252″ (28.4″ H2O) fell between Christmas Eve and February 28th. Compared to a meager 70″ of snowfall (6.7″ H2O) that fell during November, most of December, March and April combined. For the number geeks out there: 78% of our snow fell during only 38% of the season.
Snow depth is shown in the graph below:
Don’t forget about the BeadedStream snow temperature array. This shows snowpack temperature vertically every 10cm (4″) and is great for watching the pack turn isothermal. It’s located near the SNOTEL site and will hopefully be up and running until June!
AIR TEMPERATURE – (Sunburst weather station 3,812ft)
A generally cool season all in all. The early season cold period (Nov-Dec) produced 2-3 feet of faceted snow and subsequently became quite reactive in late December and January once it was buried by the holiday onslaught. There were several large avalanches, including two close calls (Tincan and Repeat Offender). Additionally, the mid-season stormy period was interrupted by a couple days cold snap in late January. The cold snap followed 2 days of rain to 2,500′ (late January crust) and is responsible for the weak snow over a crust set up that produced a handful of large avalanches during mid to late February.
WIND – (Sunburst weather station 3,812ft)
Sunburst had a much milder year for winds, compared to last season when we had record setting gusts. The mid-season stormy period is clearly evident by the increase in easterly wind from Dec 24th till the beginning of March.
Current weather can be found on the CNFAIC weather page as well as MountainWeather.com’s Alaska page.
Thank you for checking the avalanche advisories this season. Have a safe spring and summer!!
|04/19/21||Turnagain||Avalanche: Triangle, Seattle creek||Will Morrison|
|04/18/21||Turnagain||Avalanche: Turnagain Pass Road Obs||Andy Moderow|
|04/18/21||Turnagain||Observation: Seattle Ridge, approximately 300 yards south of the up track||Brent Byrne|
|04/17/21||Turnagain||Avalanche: Road obs||Johnston-Bloom / Moderow Forecaster|
|04/16/21||Turnagain||Avalanche: Seattle Ridge||Wendy Wagner Forecaster|
|04/16/21||Turnagain||Avalanche: Turnagain Pass, non-motorized side seen from Seattle Ridge||CNFAIC Staff Forecaster|
|04/16/21||Turnagain||Observation: Sunburst||Lance breeding|
|04/15/21||Turnagain||Observation: Tincan||Schauer/ Rothman Forecaster|
|04/13/21||Turnagain||Observation: Turnagain Pass Road Obs||A Schauer Forecaster|
|04/12/21||Turnagain||Observation: Tincan||Johnston-Bloom / Latosuo Forecaster|
Status of riding areas across the Chugach NF is managed by the Glacier and Seward Ranger Districts, not avalanche center staff. Riding area information is posted as a public service to our users and updated based on snow depth and snow density to prevent resource damage at trailhead locations. Riding area questions contact: firstname.lastname@example.org
|Area||Status||Weather & Riding Conditions|
This is a general backcountry avalanche advisory issued for Turnagain Arm with Turnagain Pass as the core advisory area. This advisory does not apply to highways, railroads or operating ski areas.