Cold Halloween for Boulder County, but Snowfall Expected to Melt in Time for Trick-or-treating

October 30, 2018 GMT

If you haven’t decided on a Halloween costume yet, you might want to consider something that involves a heavy coat.

After a weekend of sunny skies, temperatures are expected to drop into the 40s and 30s and Boulder could receive up to 3 inches of snow overnight.

The National Weather Service is calling for snow in the western areas of Boulder County on Tuesday into Wednesday, with 1 to 3 inches of snow in the city of Boulder and the foothills 3 to 10 inches depending on elevation. Other areas like Longmont will likely only see a few flurries, but it still will be cold.

“The continental divide and areas close to that will see the most,” said Russell Danielson with the National Weather Service.

But Danielson said it is likely the snow will not be on the ground by Halloween night.

“It should mostly be melted, since temperatures (Wednesday) should climb into the mid 40s,” Danielson said. “It should mostly be gone and cleared off the sidewalks and roads.”

But while it might not be a white Halloween, it will be a chilly one, with temperatures in the low 40s and upper 30s. So that lifeguard costume?

“We do not recommend that,” Danielson said.

But Boulder County residents have likely already been planning on ditching the hot nurse costume for a warm nurse costume, since Halloween is frequently mentioned as the time to begin expecting snow. While the region already saw a large snowstorm earlier this month , local meteorologist Matt Kelsch said there is some statistical truth to the theory.

“Snow on Halloween is a reputation around here,” Kelsch said in an email. “The Boulder climate record shows that the phrase ‘almost always’ is a bit of an exaggeration, but it’s easy to see where the snowy reputation comes from. In the last 30 years there has been measurable snow five times on Halloween. But if we look at the week centered on Halloween there has been measurable snow 16 out of the last 30 years, or 53 percent of the time.

“By comparison the one-week periods that include Thanksgiving, Christmas, Presidents Day, and St. Patrick’s Day all have about a 60 percent chance for measurable snow. So Halloween week does signal the ramp-up to winter season snow probability.”

After Halloween, Danielson said things will begin to warm up a bit.

“We’ll warm up a little bit on Thursday to the mid 50s, then upper 50s on Friday, and the same thing on Saturday, and then get stuck in a very similar patter all the way through Monday,” Danielson said.

Mitchell Byars: 303-473-1329, byarsm@dailycamera.com or twitter.com/mitchellbyars