"According to the Associated Press, the snowpack levels are almost too deep to measure in some parts of northern Colorado, where the snowpack is a minimum of 200% it's annual average."
This morning there was like 7" of fresh snow on the ground. It's 2pm and it's already melted off the grass. There is easily a 3-4 foot base on Breckenridge Mountain and all the surrounding mountains. It's coming.
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West is Next Flood Fear
by Jonathan Erdman, Sr. Meteorologist
Updated: May 20, 2011 5:00 pm ET
You've no doubt heard about the historic flood in the Mississippi Valley this spring. However, another area is just gearing up for what could be a major flood event in the coming days and weeks.
A succession of storms this winter and spring have loaded much of the Rockies, Cascades, and Sierra with a massive snowpack.
To illustrate this, the image below indicates the water content in the snowpack as a percent of average for this time of year. The dark purple squares indicate at least twice the average snowpack is in place over the Wasatch, northern Colorado mountains, Sierra, and parts of the Cascades. Incredibly, there is 4 times the average snowpack in parts of the Wasatch mountains right now!
According to the Associated Press, the snowpack levels are almost too deep to measure in some parts of northern Colorado. There have already been some minor mudslides that have damaged a few homes in Utah, and a mudslide 25 miles south of Jackson, Wyo. closed a part of U.S. 26.
Bottom line...there's a fairly simple reality ahead: Except over the highest peaks, this snowpack will have to melt over the next few weeks as temperatures soar.
One river basin already being hit hard is the North Platte River Valley. As you can see in the image below, the North Platte River's source is in the mountains near Steamboat Springs, Colo. It then flows north into Wyoming, turns east through the city of Casper, then flows southeastward into Nebraska.
According to the Associated Press, Saratoga, Wyo. is building a 3-foot berm made of dirt and sandbags on both sides of the river to protect the town.
Of more immediate concern is downstream. According to the weekly Drought Monitor discussion released by NOAA on May 17, it was estimated Lake McConaughy, a reservoir in western Nebraska near Ogalalla, has about a million acre feet of storage available. As of this writing, it is estimated at 94% capacity. Problem is, the discussion estimated there may be 2 million acre feet of water in the central Rockies snowpack.
Downstream of Nebraska's largest lake is the city of North Platte. The river has already exceeded its previous record set in 1971 (See latest river stage). According to the North Platte Telegraph, the North Platte Regional Airport has ordered sandbags to protect a levee that, if breached, could flood out emergency generators and submerge the terminal with up to 2.5 feet of water.
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Full article:
http://www.weather.com/outlook/weather-news/news/articles/flood-fears-west_2011-05-20
