La Nina pattern brings snow to mountains, wind to plains

By Cherry Sokoloski
North Forty News

It's been a strange winter so far. The northern mountains of Colorado have been pummeled with snow, while the plains are dry as dust. High winds have ripped shingles from the rooftops, raised havoc with fences and sent Wellington street signs flying, not to mention giving numerous residents bad hair days.

This year's first snowpack measurements were taken in late January, and results on the Poudre showed a phenomenally good snowpack for this time of year, just as skiers have reported. There were good snow depths from Poudre Falls up to Cameron Pass.

All five Poudre drainage sites had above-average snow depth, and water content in the snow was better than normal at the high-mountain sites. Compared with last year at this time, the numbers are dramatic. Cameron Pass had a whopping 59 inches of snow, compared with 13.8 inches last year; at Joe Wright Reservoir, the snow depth was 49 inches, up from 10.6 inches last year; Deadman Hill measured 43 inches, compared with 10.3 inches in 2005; Chamber's Lake was at 31 inches, compared with 2.3 last year; and at Big South the depth was 20 inches, with last year's only 1.7 inches.

"It's the best start to a snow season in a long time," commented John Fusaro of the Natural Resources Conservation Service.

Dry on plains

By contrast, conditions on the plains have been so warm and dry that Gov. Bill Owens likened the fire danger to that of a typical July and issued a fire ban on state lands in early January. Three large wildfires along the Front Range frightened folks in January, including a 350-acre fire near Carter Lake that caused several evacuations and came whisker-close to destroying a home.

On Jan. 28, a quickly moving grass fire on the Cathy Fromme Prairie Natural Area burned about 50 acres and got the attention of residents in nearby neighborhoods. The fire, apparently started by a cigarette butt thrown from a car, burned on the west side of Taft Hill Road, north of the county landfill, in tall prairie grasses.

So what's up with this weird weather?

Nolan Doesken, assistant state climatologist, said some of the weather patterns have been typical of a La Nina pattern. Traditionally, La Nina brings dry weather to the southern Rockies, wetter weather to the northern Rockies and more high winds than usual. However, the La Nina pattern is typically cold, whereas local temperatures until recently were "profoundly above average," Doesken said. For almost four weeks in December and January, temperatures averaged about 15 degrees above normal.

Another factor has been the direction of the winter storms. So far, snowstorms have come into Colorado from the west, as opposed to upslope patterns from the east. As a result, snow has been dumped on the mountains but not much has reached the plains.

In fact, snowfall is running more than 2 feet below average on the plains. By the end of January, Doesken said, Fort Collins would normally receive about 31 inches of snow. By contrast, this year had brought only 4.7 inches as of Jan. 26.

"Everyone along the Front Range is below average," he said.

While winds have been strong, there have been no record-breakers at the Colorado State University weather station, Doesken said. Nonetheless, numerous gusts above 60 miles per hour have been recorded.

Farmers nervous

The unusually dry weather on the plains is making some farmers nervous. "We're still in serious trouble from the drought," said Howard Diehl, who farms northeast of Wellington with his sons. "The soil moisture has not recouped--not by a long ways."

Winter wheat got a healthy start last fall with good rains in the area, but now it's drying out fast. If the current warm, windy weather persists, blowing dust will tear up the wheat in the fields.

Diehl's observations are borne out by the research of soil scientist Neil Hanson of Colorado State University. His office has several soil testing sites in Colorado, and he said the Sterling and Briggsdale sites are showing soil moisture even lower than in the bad drought year of 2002. The soils were "completely emptied by the drought," he said, and it will take several years of average or above-average moisture to recover.

Hanson said the little moisture that is in the soil is just below the surface, and the ground is very dry below that. Conditions like these are bad for the root systems of crops and will likely affect yields.

Steve Smith, manager of North Poudre Irrigation Co., said it's too early to predict what kind of irrigation conditions will be here in the spring. He echoed others' observations about the poor subsoil moisture, however. If the weather stays dry, Smith said, he'll be pressured to make early irrigation deliveries and there will be considerable shrinkage (loss of water due to absorption) in the irrigation ditches this year.