"Diamond Dust" Graced Vermont's Air On Frigid Tuesday, Maybe Again Saturday?

As large swaths of Lake Champlain froze in Tuesday's 
frigid temperatures, "diamond dust" or ice crystals forming
in the clear Arctic air created a hazy, otherworldly quality.
This is a view of the lake from South Hero, Vermont. 

 The National Weather Service in South Burlington released a nice explainer on social media about that icy haze you might have seen in the air Tuesday.  It's definitely worth it to check it out.

To summarize it, when it gets really cold, it's hard for snowflakes to form. Snowflakes like to form when the temperature aloft a bit is between minus 5 and 15 above. 

When it gets colder than that, ice crystals form instead.  That's especially true if there's some moisture coming from relatively warm ground or open water.    

The ice crystals, or diamond dust in the air can do some cool things.  First off, I actually liked that "hazy" quality the diamond dust created in the blue sky on Tuesday. It softened the sharpness of that cold look. 

Even better, the icy crystals can create something called light pillars. These pillars consist of pillars of light on either side of the sun.  Or, at night, they can be beautiful pillars of light emanating from street lamps and other outdoor lighting. 

At sunset, the diamond dust can enhance alpenglow, which is that orange hue snow encrusted mountains often have at or just after sunset. 

Equipment at the many automated weather stations scattered through Vermont and the rest of the nation have a little trouble discerning what it is in the air when there we have those diamond dust ice crystals.  Yesterday, I saw a number of false reports of haze or blowing snow, when the real issue was diamond dust.

In really cold Arctic climates, like in Siberia or interior Alaska, the ice crystals can thicken into a dense ice fog. Usually steam exhaust from cars and buildings create this thick ice fog in cities like Fairbanks, Alaska when it's super cold and an inversion traps the moisture. 

It's forecast to be quite cold and probably mostly clear again Saturday.  That means we could easily have another encounter with diamond dust.  Too bad it's not real diamonds, though.