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Snow and ice, the sugar and spice of winter weather

PORTLAND, Ore. (KOIN) – Raise your hand if you like snow!

We aren’t strangers to snow in the Pacific Northwest, especially up in the mountains — but sometimes we don’t get that much snow in the valley. That was not the case this last weekend, as a winter storm brought snow and ice to the Willamette Valley.

Look at some of the photos of the snow that we had over the course of about four days (February 11-14). Look at the mound of snow on the table in the middle photo. It looks so fluffy!

Have you noticed that snow has different consistency?

The moisture consistency that comes with snow can vary from snow storm and location.

What is the reasoning for wet snow that packs well versus powdery snow that is very light and powdery?

Wet snow generally means the temperature aloft will drift above freezing and then some of the snow will melt. The liquid content of the snow will be higher. Well then, if it is powdery dry snow, the temperature aloft is going to be well below freezing all the way and that snow will fall in a cold and freezing environment from the top to bottom.

Weekend Meteorologist Joseph Dames

Interested in the way things work above our head? You can learn about precipitation type here.

MOVING ON

I remember as a kid getting real excited about playing out in the snow. I often thought that I would want to be a snowplow driver when I got older (seasonal job, right?). I thought it would be so fun to shove around snow. One of the best things about being a kid is being able to think up some potential fun jobs! Well, some of the things you learn right now may spark a larger interest in snow.

Would you want to work up in nature and be the person who helps measure the snowpack during the winter?

Well you’ll need to know some of the terms:

Snowmelt: The water that you get when snow melts

Snow Depth: The total amount of snow on the ground (new and old)

Snow Water Equivalent (SWE): The amount of water that would be obtained if the snow sample were completely melted

WHAT ABOUT ICE?

Ice Accretion: When ice builds up on objects like trees when exposed to freezing rain (see photos above)

Watch the video below. Chief Meteorologist Natasha Stenbock explores ice accretion during a Portland ice storm.

HOW DO YOU MEASURE ICE?

In most cases, like the photo above, you can see that the measurement is taken from the outside of the ice through the branch itself. You then subtract the branch, leaving the amount of ice accretion.

There are times that you have to measure both sides. How do you do that?

Courtesy: NWS

It will take a some math, but when you are measuring ice on a free object, such as a twig, you typically will measure the thick side and then the thin side (excluding the branch) and then you divide by two.

For example, the thick side measures 3/4 of an inch and the thin side of the branch has a layer of 1/4 inch, you then add them and divide by two. You will get 1/2 inch of ice.

Now ice is is measured to the nearest tenth-inch, so you can see a conversion of that in the chart below.

Courtesy: NWS