The National Weather Service Forecasts-

TODAY...MOSTLY CLOUDY IN THE MORNING THEN BECOMING SUNNY. LOCALLY WINDY. ISOLATED SNOW SHOWERS IN THE MORNING. HIGHS AROUND 14. NORTHWEST WIND 15 TO 25 MPH BECOMING NORTHEAST IN THE AFTERNOON. WIND GUSTS UP TO 40 MPH IN EXPOSED LOCATIONS.

TONIGHT...SNOW DEVELOPING LATE. SNOW ACCUMULATION 1 TO 3 INCHES. LOCALLY WINDY. LOWS 5 TO 11. NORTHEAST WIND 20 TO 30 MPH WITH GUSTS TO AROUND 45 MPH IN EXPOSED LOCATIONS. WIND CHILL TO 20 BELOW.

TUESDAY...SNOW. SNOW ACCUMULATION 3 TO 7 INCHES. STORM TOTAL
SNOW ACCUMULATION OF 4 TO 8 INCHES. HIGHS 19 TO 25. SOUTHEAST
WIND 15 TO 25 MPH.

Temperatures have fallen by roughly 30f degrees over the last 48 hours. Mountain top temps are hovering barely in the positive numbers this morning.

Winds although mostly calm yesterday have picked up after 3am this morning and are now hovering from 10-20mph and gusting higher. Stronger winds can be found along the channel. Sheep mountain is gusting over 40, Mt Roberts into the mid 20's and Eaglecrest is still in the teens. These winds are forecast to increase throughout the day. As the winds roll from NW to NE avalanche danger along the channel will increase.

We received about 4mm of precipitation in the last 24 hours and 13mm in the last 48 hours. This left about 8mm of light dry snow on top of a few mm from the day before for a total of about 10mm(4\") of new snow in the last 48 hours.

This is a good snowpack with snow that came in at above freezing temperatures earlier in the week and continued to get colder stacking light dry snow on heavier snow that should have bonded fairly well to the old snow surface.

The primary concern for today is windloading. Winds have been primarily from the SW to West. This morning winds are from the North and will be rolling around to the NE directly loading our urban starting zones.

Avalanche danger is Moderate to Considerable this morning. Natural Avalanches are possible as the winds roll to the NE and start to load our urban paths.

The instability will be near surface and no large avalanches are expected to affect our urban zones.

Human triggered avalanches are possible near summit and ridgeline in isolated windloaded pockets. Be aware that as winds pick up and windloading continues danger levels will increase slightly.

As we go through tonight into tomorrow be aware that avalanche danger will start to greatly increase. Temperatures are predicted to warm up a great deal and precip volumes and new snow accumulations are also forecast to increase a fair amount. All of this during a continued windloading event which will lead to further instability.

Today the snowpack is right side up and building a windslab. Tomorrow the snowpack will be upside down and continuing to build a windslab of heavier snows on top of this really light dry snow in place today with a soft slab building.

Tomorrow into Wednesday we will have all the ingredients leading to another avalanche cycle.

Today avoid places like the Flume Trail. Avoid walking on the closed roads above the Behrands Neighborhood. Avoid parking and walking along Thane Road.

Althought these avalanches are not predicted to be very large in nature, due to the light dry cold snow they have the potential to run quote fast and far pushing a powdercloud in front of them.

As mentioned todays storm is right side up... but tomorrows snowfall event will be a different story with a great deal of warming and winds creating an upside down snowpack.

Upside-Down Storm:

Most snow comes from cold fonts, which usually start out warm and windy but end up cold and calm. But sometimes snowstorms deposit denser, stiffer snow on top of softer, fluffier snow. We call this ?upside down? snow. We often call it ?slabby? or ?punchy? meaning that you punch through the surface slab into the softer snow below, making for difficult riding and trail breaking conditions. It also means that we need to carefully monitor avalanche conditions within the new snow because?by definition?a denser slab has been recently deposited on top of a weaker layer, which should make anyone?s avalanche antennae stand at attention. Most instabilities within upside-down snow stabilize within a day or two.

The kind of weather conditions that often produce upside-down snow include warm fronts, storms in which the wind blows harder at the end of the storm than the beginning, or storms that end with an unstable airmass, which can precipitate a lot of graupel within instability showers.