There could be brief, intense snow showers known as snow squalls in the Twin Cities on Thursday.
Meteorologist Sven Sundgaard says conditions for snow squalls are favorable as a cold upper-level low has brought with it very cold air aloft, which generates instability.
"Think of the mix of spring sunshine and winter air aloft. Even though we won’t see much sun, a peek or two or even thinning of the clouds will be enough," said Sundgaard. "These snow showers develop in a convective way, with rapidly rising air similar to a thunderstorm, though on a smaller scale with less depth. As we warm up Thursday, even slightly, we’ll see midday and afternoon bursts of snow pop up."
You can see the dark blue colors, which indicate heavy bursts of snow, on the HRRR model's radar simulation from 10 a.m. to midnight.
They’ll be brief: 10 to 20 minutes and can drop a quick coating, mainly on grassy surfaces. They can be intense and cause low visibility, in part because of the big flakes that will form in the perfect dendritic layer of the atmosphere, according to Sundgaard.
Dendrites (big, fluffy flakes with all the arms) form at temperatures between 0 and 10 degrees Fahrenheit. Today that layer is at 3,000 to 8,000 feet above the ground, as you can see in this sounding.