UW Extension Information Can Help Assist Flood Preparations
May 20, 2011 — The flood issue contact person for the University of Wyoming Cooperative Extension Service offered simple advice as the state wallows in the calm before possible floods from snowmelt.
"The biggest thing is to pay attention to the weather," said Ron Cunningham, extension educator in Fremont County.
Mother Nature had dumped 2 inches of rain in the Lander area Wednesday night. The snowpack above Cunningham in the Wind River basin hovered at about 160 percent of normal Friday morning.
Cunningham said climate conditions in his area are similar to last year, when residents there had to wrestle floodwaters from the Popo Agie and Wind River.
He wasn't predicting floods - only issuing a caution.
"What really caught us off guard last year is that it was real cool, and then we got snow in the mountains - like last night (Wednesday)," said Cunningham. "Then, all of a sudden last year, we got a Chinook wind, and it really warmed up."
He said UW extension's Wyoming Extension Disaster Education Network (at www.uwyo.edu/WYODISASTERHELP) offers information to help those facing floods. Click on Floods under Natural Disasters on the left-hand side of the page
Numbers from the UW Water Resources Data System, based on data from the Natural Resources Conservation Service SNOTEL sites, show eye-opening percents-of-average of some Wyoming basins as of Friday morning: Powder-Tongue - 206 percent; Belle Fourche - 220 percent; Upper North Platte - 207 percent; Lower North Platte - 167 percent; Little Snake - 210 percent; Upper Green River - 210 percent; Lower Green River - 196; Upper Bear - 283 percent.
Wyoming's high and low elevations have lots of snow looming above already-saturated soils.
SNOTEL is designed to help predict total water yield over the course of the runoff season, generally late spring through summer, said Steve Gray, Wyoming state climatologist, based at the University of Wyoming.
"Where the network is less effective - and it's not really designed to do this anyway - is for predicting what might happen over the shorter term," he said. "At the moment, we have lots of water sitting around in the lower elevations and in the higher elevations. So, it's this combination of snow and saturated soils down in the valleys/basins plus the potential for high elevation runoff that is contributing to such high flood risk."
Snowpack and other information are available at www.wrds.uwyo.edu/wrds/nrcs/nrcs.html.
Current streamflow information from the National Weather Service is available at http://water.weather.gov. Click on Wyoming then the city of interest. Minor flooding was reported Friday morning at Henry, and rivers and streams at near flood stage at Fort Laramie, Little America in western Wyoming and near Saratoga.