Hatcher Pass

Forecast Expired - 2018-12-09

Above 3,500ft Moderate

2,500 to 3,500ft Moderate

Below 2,500ftLow

Degrees of Avalanche Danger

Avalanche Activity

A couple human triggered avalanches were reported early in the week around the Willow-Fishhook Road area and Hatch Peak. They were 1-3 feet deep, in wind loaded areas, likely failing on basal facets. 

We observed a couple slab avalanches which may have occurred during wind and snow events this week on Hatch Peak, NW, approx. 4200′, approx. D1-2.

Numerous reports were made both through the observation platform, and in meeting users in the field, describing whumphing and/or cracking in the mid to upper elevations throughout HP.

Overall visibility has been challenging this week, limiting the ability to date and size natural avalanches.

Weather

This week’s weather at 3550′:

Temps averaged 28ºF, with a low of 17ºF and a high of 36ºF.

IM reported 11-12″ of new snow on 12/2-3  this week with 1.2″ of water (SWE). A few flurries came in through the week, with 1-2″ of new snow on 12/6-7 with 0.1″ water (SWE).

Overnight at 3550′:

Temps averaged 32°F.

No new snow overnight.

This week’s weather at 4500′:

Temps averaged 24ºF, with a low of 13ºF and a high of 29ºF.

Winds averaged SE 10 mph, max 29 mph . Gusts averaged SE 18 mph, max gust SE 47 mph.

Overnight at 4500′:

Temps averaged  28ºF overnight, with a Low of 27ºF .

Winds averaged 10 mph overnight. Yesterday winds trended stronger from the ESE through the day, relaxing around midnight to NE. Max gust SE 27 mph.


NWS Rec Forecast HERE


State Parks Snow Report HERE

Additional Information

TREND: 

As of this morning wind speeds at 4500´at the Marmot Weather Station have relaxed. If mountain top wind speeds increase and sustain 15-20 mph or more through the day, expect the WIND SLAB and PERSISTENT SLAB avalanche hazards to increase to CONSIDERABLE at the upper elevations on leeward slopes towards the end of the day and into tomorrow.

Wind slabs will be a surface avalanche problem, easier to predict, mitigate and smaller in size than the persistent slab problem, which will be more difficult to predict, deeper, and a larger avalanche. Any rapid load, such as wind loading has the potential for overloading and increasing the likelihood for triggering persistent slab avalanches.

Warm temperatures today may limit the availability for snow transport. The NWS wind forecast for today is highly variable, so keep tabs on the wind speeds through the day and adjust your plans accordingly.


Southcentral Alaska Mountain ForecastNATIONAL WEATHER SERVICE Anchorage AK415 AM AKST Sat Dec 8 2018The Hatcher Pass Mountain Forecast covers the mountains in theHatcher Pass Recreation Area.This forecast is for use in snow safety activities and emergencymanagement.                   Today        TonightTemp at 1000`      27-33 F      20 FTemp at 3000`      28-35 F      18-26 FChance of precip   80%          100%Precip amount(above 1000 FT)    0.24 in      0.30 inSnow amount(above 1000 FT)    2-4 in       4 inSnow level         1500 ft      sea levelWind 3000` ridges  SE 6-26 mph  E 0-14 mph