About these ads

Climate: How hot will it get in Colorado?

State releases draft climate change report, comments wanted

dg

How warm will it get in Colorado?

By Summit Voice

FRISCO — Climate experts say it’s about to get warmer —probably much warmer — in Colorado. A draft state climate report released this week for public comment shows that Colorado has warmed by 2.5 degrees Fahrenheit in the past 50 years. By the middle of this century, summer temperatures will be higher than in all but the hottest years, with another 2.5 to 5.5 degrees of warming expected. Continue reading

About these ads

Climate: Storms bolster Colorado snowpack

ij

Colorado’s snowpack is above average as of Feb. 1.

Feb. 1 snow survey results suggest decent spring runoff for most of the state

By Summit  Voice

FRISCO — Colorado’s snowpack surged to above average in late January thanks to a strong storm that brought snow statewide, federal water experts said last week. The Feb. 1 snow survey showed the average snowpack across the Colorado mountains at 107 percent of average, and 152 percent above last year’s Feb. 1 reading.

As of Feb. 1, only the Upper Rio Grande (82 percent) and San Juan (79 percent) basins in the southern part of the state were below average, according to the USDA’s Natural Resources Conservation Service. Continue reading

Colorado snowpack lingering in the northern mountains

Southern part of state still gripped by drought

sdf

Colorado’s June 5 snowpack map is a patchwork quilt of contrasts.

By Summit Voice

FRISCO — Springtime in the Rockies was a tale of two states in Colorado. The snowpack rebounded in the northern mountains, which benefited from a series of wet spring storms, but the southern half of the state was dry and warm, with serious drought conditions persisting in the Rio Grande, as as the San Miguel, Dolores, Animas and San Juan basins.

This year’s statewide snowpack peaked April 21, several weeks later than the average date, and cool weather helped further delay snowmelt across the higher elevations, resulting in a statewide June 1 snowpack  at 92 percent of median, according to Randy Randall, acting State Conservationist with the NRCS.

“This respectable percentage is due mainly to the generous amount of snow that remains across northern Colorado. In contrast, the snowpack in the southern portion of the state is nearly depleted even at the higher elevations,” Randall said. Continue reading

Colorado: Dust layers a factor in record-early snow melt

Report links wind-blown dust with early runoff

Dust from the desert Southwest is visible on the snow at Loveland Pass, Colorado in this file image from 2010.

NASA Satellite images can trace the dust plumes back to their source.

By Summit Voice

SUMMIT COUNTY — Along with above-average temperatures and dry and sunny weather, spring dust storms in March and April likely were a significant factor in this year’s record early snow-melt season, according to the Silverton-based Colorado Center for Snow and Avalanche Studies.

Snow that’s darkened by wind-deposited dust absorbs much more heat and hastens the warming of the snowpack to an isothermal state (32 degrees from top to bottom).

In its year-end report, the center explains that the dust layers continue to absorb and add solar energy to the snowpack long after the original dust layer is deposited.  Continue reading

Colorado: Snowpack and runoff near record lows

Statewide snowpack now just 19 percent of average; summer streamflows expected to be less than 50 percent of average

Straight Creek, Dillon’s primary water source, could see record low stream flows this year. PHOTO BY BOB BERWYN.

By Bob Berwyn

SUMMIT COUNTY — The snowpack and runoff news keeps getting worse and worse in Colorado, as April brought another big drop in the numbers. The downward trend doesn’t bode well for the summer, and while reservoir storage is currently just above average statewide, those levels will quickly drop when irrigation season begins.

In Summit County measurements at Hoosier Pass by the Center for Snow and Avalanche Studies show that, at times, the snowpack was melting at a rate of an inch per day, accelerated by a layer of dark-colored dust that reduced the snow’s albedo.

“Statewide snowpack looks to have peaked around March 12, a month ahead of the average peak date, and began melting in late March at rates typically not observed until May,” said Phyllis Ann Philipps, State Conservationist with the Natural Resources Conservation Service. Continue reading

Drought conditions expand in north-central Colorado

March precipitation across the intermountain West shown as a percentage of normal.

Spring and summer runoff may reach record-low levels 

By Summit Voice

SUMMIT COUNTY — The mid-April snowfall helped reduce the immediate fire danger, but didn’t do much to alleviate the season-long moisture deficit. In fact, the region as a whole is drier now than it was at the beginning of March, according to the Western Water Assessment’s April report.

To-date, April precipitation at the Dillon weather observation site is 88 percent of average, at .65 inches. For January through March, the Dillon site has measured 1.94 inches of water compared to the average 2.74 inches, which is 71 percent of the historic average.

On April 1st, 17 Colorado SNOTEL sites set new record lows, while 16 others were near-record lows. By April 9th, several sites had either melted out with record early melt-out dates or were on a likely trajectory to do so.Spring and summer runoff in some areas may approach record-low volumes. Only 5.2 percent of the country still is covered by snow, the lowest level since 2004. Last year at this time, it was 22 percent. Continue reading

Colorado weather: Return of Ullr?

Incoming weekend storm could bolster runoff in parts of Colorado

Here's what the circulation of weather systems in the northern hemishpere looks like from the IPS Meteostar satellite in geostationary orbit over the North Pole. Click on the image to see the animated loop.

An afternoon satellite image shows big thunderstorms developing over southeastern Colorado and northeastern New Mexico in advance of the approaching Pacific storm.

By Summit Voice

SUMMIT COUNTY — The recent spell of warm and dry weather finally broke Wednesday with some afternoon thunderstorms, but not before yet another high  record was broken, as the temperature reached 63.2 degrees in Frisco at 11:44 a.m. The old record, 61 degrees, was set in 1960, and it may be a few days before the balmy weather returns.

In fact, Colorado could see a cool and wet weekend, which might help put a dent in the statewide moisture deficit, with the lowest-ever April 1 snowpack reading on record and still plummeting fast. The Colorado River Basin, including Summit County, reported the lowest reading in the state at only 37 percent of average.

A weather system set to roll across the state this weekend could bring some relief. It’s still to early to tell which parts of Colorado will see the most snow, as the large low pressure system will be cut loose from the main west to east flow and will likely wobble around quite a bit without a clear trajectory. Continue reading

Summit County: More flood warnings issued

As of May 31, the Colorado Water Conservation Board put Summit County into a flood advisory zone where minor flooding is expected. Click on the map to visit the CWCB's flood info page.

Mid-week warmup is expected to raise river levels’ low-lying areas at risk for flooding

By Summit Voice

SUMMIT COUNTY — With Summit County already in a flood advisory zone identified by the Colorado Water Conservation Board, local officials are saying that now is the time for sand-bagging.

“Effects of the runoff are already being reported around the county,” said Sheriff John Minor. “We’re seeing rising waters in those low-lying areas that typically experience springtime flooding, like the Lakeview Meadows and South Forty subdivisions.”

The statewide snowpack is about 250 percent of normal for this time of year, and warmer weather the next few days could send streamflows spiking to levels not seen in many years.

“We haven’t seen these conditions since 1984, 1995 or 1996, all years where we saw significant flooding issues throughout the county,” said county emergency manager Joel Cochran. Just because your property hasn’t experienced flooding before, don’t automatically assume you’ll stay dry this year, Cochran said. Continue reading

Summit County: Local streams on state flood-watch list

Local officials will hold a high water preparedness meeting May 9 in Frisco

Sandbags will be stockpiled in Summit County to help residents protect their property from potential high water. Click on the map to see the full county high water packet.

State officials are using this map of snow-water equivalent in the snowpack to help assess the risk of high runoff.

By Bob Berwyn

SUMMIT COUNTY — Expecting heavy runoff in the next few weeks, Denver Water has ramped up releases from Dillon Reservoir to 255 cubic feet per second as of April 29. By next week, the flows in the Lower Blue River, north of Silverthorne, could be raised to as high as 400 to 500 cfs, said Bob Steger, raw water manager for the Denver utility.

“The purpose of these increased releases is to create space in the reservoir. Hopefully, the space we are creating will allow us to capture the peak inflow and attenuate the peak outflow,” Steger wrote in an email to Summit County officials and media.

The snowpack in the Upper Colorado River Basin as a whole was at about 150 percent of normal, and it ranges even higher than that in parts of the Blue River Watershed. The Snake River, the Blue River and Tenmile Creek are all listed on an April 21 flood watch bulletin from the Colorado Water Conservation Board. Click here to visit the CWCB’s flood preparedness page. You can view and download a state high-water packet by clicking here. Continue reading

Western water supplies will take big climate change hit

Western water resources are at risk from climate change, according to a new report from the Bureau of Reclamation.

BuRec report says higher temps, changes to runoff likely under most climate change scenarios

By Summit Voice

SUMMIT COUNTY — Water supplies in the western United States could be hit hard by projected global warming impacts, including temperature increases of 5 to 7 degrees across the region, according to the Department of Interior, which this week released a new report assessing how climate change could affect water operations, hydropower, flood control, and fish and wildlife.

The report to Congress was prepared by the Bureau of Reclamation and represents the first consistent and coordinated assessment of risks to future water supplies across eight major Reclamation river basins, including the Colorado, Rio Grande and Missouri river basins.

The report forecasts an 8 to 20 percent decrease in average annual stream flow in several river basins, including the Colorado, the Rio Grande, and the San Joaquin. Big changes in the timing and volume of spring runoff are likely to have impacts on agriculture and hydropower operations. Continue reading

Follow

Get every new post delivered to your Inbox.

Join 7,238 other followers