If it’s winter, weather will be wild, windy

From back-to-back snowstorms around Halloween to wind-driven rain squalls after Thanksgiving, this winter has started out to be fairly typical for northern Colorado, heavy tree damage notwithstanding.

“Historically, La Niña conditions (cooler than average tropical temperatures in the southern Pacific Ocean) like those that started last summer mean warmer and drier winters in the southern states, and cooler and stormier winters in the northern states,” explained Nolan Doesken, state climatologist at Colorado State University. “Colorado is smack in the middle, so we could be looking at a winter much like last year.”

Winter in Larimer County is usually dry and windy at lower elevations and east of Red Feather Lakes, and snowy nearer the Continental Divide, Doesken said.

It’s the high winds that can cause the biggest problems for those trying to keep snow off county roads. Dale Miller, director of the Road and Bridge Department, said even a relatively light snowfall can be whipped into drifts pretty quickly, especially near the foothills.

“The most efficient way to plow is with a dump truck with a blade attached,” Miller said. “But in some of our most wind-prone areas, trucks can have a hard time getting through a drift and then getting it to the side of the road.”

The county maintains 33 dump trucks that can carry a snow blade, deployed in three facilities around the county. Each facility also houses two road graders, one with a v-plow and one with a two-way angle plow, that can tackle bigger drifts.

The county does not use any liquid de-icers such as magnesium chloride to treat road surfaces, according to Miller. What the trucks do lay down depends on where they are plowing — and whether the state can afford salt this year.

“In Livermore and Estes Park, where there is covered storage, we share the treatment material with CDOT and it’s usually a sand-and-salt mixture; we buy a salt product from Fort Collins (to use in the south end of the county),” Miller said. “In Stove Prairie and the Laramie River area, where the storage is open, it’s just sand, to minimize the (salt) runoff.”

Even more difficult than battling drifts is deciding when to call out the plows, Miller added.

“We have to look at how hard it’s snowing, how long it’s expected to snow, how warm the ground is when it starts, whether the roads are paved or gravel, and whether the wind is blowing in each area of the county,” he said. “It’s a judgment call for every storm. But it’s hard to be proactive; we can’t plow before the flakes fall.”

Miller’s department only deploys plows to county-maintained roads. To find out who you should be expecting to clear your streets, contact Road and Bridge at 970-498-5650.

Miller’s best tip for driving in winter weather: Don’t if you don’t have to. But if you do, make sure you have emergency supplies in your vehicle: shovel, blankets, flashlight, a gallon of water, snacks and something like kitty litter to create traction. And watch out for the plows, since a vehicle completely covered in snow can look just like a wind-driven snowdrift.

Anyone out driving during the first storm in late October had to watch out for downed tree limbs, especially in more urban areas. (see related story)

Falling branches were responsible for power outages affecting thousands of homes and businesses served by both Poudre Valley Rural Electric Association and Xcel Energy Inc. Some customers remained without power until late Friday, Oct. 28.

Through both early storms, Poudre School District schools remained open. However, because weather conditions may vary greatly within the geographically diverse district, it is possible that just the schools in the mountain area may be closed, or may close early during a storm.

The district’s website at www.psd.k12.co.us outlines notification procedures for those early closures, which can make students happy and leave parents scrambling.

Farmers and ranchers were among those who happy to see the October snow. Despite a bone-dry August and warm temperatures that lasted until the snow began to fall, soil moisture levels in early November were good, Doesken said. The big spring runoff in the Poudre River and soaking rains in September and October combined with the snow to alleviate some of the extremely dry conditions of recent years. Normal precipitation over the winter should keep water levels in good shape for spring planting.

“We would have to go all winter and all spring without any moisture to get us back to seriously dry conditions,” he added.

Although the odds may favor few big snowstorms on the northern Front Range between now and February, Doesken has learned one thing over 34 years watching the weather: Forecasting past next week is not yet an exact science.

“The rest of the winter is still ahead of us,” he said.