13 Apr 2012

Another great day yesterday, lots of convective activity.

A convection cloud is a cloud that forms from the air rising in that place. When the sun heats the earth, the air right above it gets warmer and rises. Because of the lesser pressure above, it cools down by adiabatic effect and when it moisture contentreaches what is called dew point temperature, it condenses as a cloud.

Usually those are cumulus clouds and their base is exactly where the air is a dew point temperature.

But once it starts condensing, the moisture give away energy in form of heat. That keeps the cloud rising. When it finally reaches a place where the temperature equals that of the surrounding air, it stops rising. That's the cauliflower top of a cumulus cloud. Each top is an air parcel that rose in a "bubble" of warm air.

If the air aloft is very cold, the "bubbles" will keep rising all the way to the top of the troposphere. The cloud is then called a cumulonimbus and it may become a thunderstorms.

At 2280 meters the temperature was -6, winds were 5-15 KPH from the E as of 06:00 Hrs.
At 1550 meters the Temperature was -2.5, 100% relative humidity and the barometer was rising.
In there Valley it is +3.

For the updated Avalanche Advisory click here: Avalanche Advisory

An interesting American site: Open Snow

Setting off a large avalanche in Japan: Touchy Conditions

Propagation Saw Test on a grand scale in Utah 140 cm wide and 11 meters long: Interesting Results

Definition of an isothermal snow pack: Isothermal

# 13 had to have something in here with a 13!

Thursday April 12 Th was the Mom's Classic