Sun dogs, also called mock suns or 22-degree parhelia made a spectacular show at sunrise today. The snow covered landscape was the backdrop, as ice crystals refracted the sunlight through the clear frigid sky. Here’s a good explanation of sun dogs from the University of Illinois.
Sundogs, also known as mock suns or “parhelia”, are a pair of brightly colored spots, one on either side of the sun.
Sundogs are visible when the sun is near the horizon and on the same horizontal plane as the observer and the ice crystals. As sunlight passes through the ice crystals, it is bent by 22 degrees before reaching our eyes, much like what happens with 22 degree halos. This bending of light results in the formation of a sundog. The difference between sundogs and halos is the preferential orientation of the ice crystals through which the light passes before reaching our eyes. If the hexagonal crystals are oriented with their flat faces horizontal, a sundog is observed. If the hexagonal crystals are randomly oriented, a halo is observed.
Wintery Smack Talk about a reality check. Minnesota’s weather message is crystal clear, winter is here to stay. Our early December winter storm battered Duluth and the North Shore for 3 days with some epic snowfall totals. I had the pleasure of meeting NWS cooperative weather observer Gordon Hommes a couple of years back in Read more →
Our winter storm has slowed a bit, but is still on track for significant snowfall tonight and Wednesday. The window for significant snow in the metro seems to favor snow increasing from the west between 9 p.m. to midnight tonight, and continuing through about 5 p.m. Wednesday. That should mean messy morning and evening rush Read more →
Major Winter Storm December is here, and winter is wasting no time on the weather maps. A major winter storm is evolving and unfolding this week. Snow is already flying up north with the storm’s lead wave, and the Mother Low is gathering strength out west. As the forecast models attempt to bring the storm Read more →
A quick update as weather conditions are changing rapidly in the Twin Cities metro area today — and this week. First, our quick late afternoon snow burst during rush hour is bad timing for metro commuters. It’s a narrow band of snow, but it’s coming down with big flakes and putting down a quick coating Read more →
I may not be the only one who noticed, but the National Oceanic and Atmospheric Administration’s Climate Prediction Center on Saturday revised the monthly outlook for December, emphasizing a colder-than-normal and perhaps snowy month coming up for Minnesota. The revised outlook certainly agrees with many forecast models for at least the first half of the month, as Read more →
Thanksgiving Gratitude I have much to be grateful for this year in the Huttner Weather Lab. I’m grateful to MPR for giving me such a great opportunity and deep support. It’s a humbling honor to be considered a (hopefully reliable) voice on Minnesota’s weather on the MPR airwaves. Thanks to you, MPR listeners and members Read more →