The National Weather Service Forecasts-

TODAY...SUNNY. HIGHS 18 TO 24. NORTHEAST WIND TO 10 MPH. WIND
CHILL TO 25 BELOW ALONG TAKU INLET IN THE MORNING.

TONIGHT...MOSTLY CLEAR. LOWS 10 TO 18. EAST WIND 10 TO 15 MPH.

TUESDAY...SUNNY. HIGHS 23 TO 29. SOUTHEAST WIND 10 TO 20 MPH.

TUESDAY NIGHT...PARTLY CLOUDY. LOWS 14 TO 20. SOUTHEAST WIND
10 TO 20 MPH.

With the warm weather from 2 weeks ago, the rain and heavy dense snow, the lower snowpack has settled and bonded quite a bit.

There are still multiple weak layers lower in the snowpack but the heavy dense snow above them appears to be supportive at this time. Be cautious as new loads are placed on these already weak layers by new snow or even by additional wind loading.

Look to see continued areas of wind loading as the snow in place is affected by winds of 10+ MPH throughout most of the next few days.

Thursday natural avalanche releases were sighted on multiple aspects due to wind loading. Be aware there are pockets of instability.

With very little snow on Mt Juneau in the urban starting zones avalanche danger is LOW at this time. Yet some of the gullies are starting to see fair snow accumulation due to crossloading from the winds.

Please remember this is not a backcountry forecast.

Please be aware that fieldwork continues to show multiple weak layers in the snowpack and natural avalanches have been sighted recently.

Backcountry danger levels could be considerably higher.

Air temperature not only determines the type of snow crystals that fall from the sky, but the metamorphic processes that occur within the snowpack.

To forecast avalanches you need to track:

?Daily temperature values (highs and lows) and range

?Temperature trend (increasing or decreasing) and rate and duration of change

Daily temperature values: Use daily high and low temperatures to determine freezing levels in the mountains as well as snow and rain levels during storms. Note the following.

?Crusts may form if temperatures rise above freezing during the day and drop below freezing at night; the crust can create a potential sliding layer for the next storm

?When temperatures remain above freezing for more than 24 hours, the upper snowpack becomes saturated from melt water and may cause wet snow avalanching.

?When temperatures stay well below freezing for long periods of time and high and low temperatures never rise above 15?F (-10?C) day and night, weak layers may develop on the surface or near the ground in a shallow snowpack; this can create a layer that fails with the next load of new snow.

Key points:

?Avalanches may occur when air temperatures rise above freezing and stay there

?Weak layers often develop when temperatures get very cold and remain that way.

Temperature trend: As temperatures increase, the snowpack undergoes settlement, deforming and becoming denser. Settlement on an incline results in creep, a slow downhill motion.

?If air temperatures increase rapidly (more than 15?F or 8?C) in less than 12 hours, the rate of creep increases, which can lead to avalanching. This is most critical when temperatures are near or above freezing because the rate of creep increases exponentially with rising temperature.

?If temperatures increase slowly over several days, settlement rates are slower. If air temperatures never rise above freezing for very long, the snowpack deforms slowly and creep rates are slower.

?As temperatures decrease, settlement and creep rates also decrease.

?Prolonged periods of cold temperatures promote the metamorphic processes that form weak layers.

?Warm days and cold nights strengthen the pack, especially overnight and during early morning hours.

?Several days of warmer temperatures followed by colder temperatures also strengthen the pack.

Key points:

?Rapid rises in temperature can destabilize a pack, while slow rises stabilize it (especially if a cooling trend follows)

?Long periods of cold temperatures build weaker snow, which isn?t a problem until the next significant snowfall