SALT LAKE CITY — So far, cooler than normal temperatures every few days has kept the largest mountain snowpack in 10 to 15 years from transforming into one of the worst flood situations in decades across many parts of Utah.
But the temperatures won't be so helpful for long.
"Temperatures will be rising to the mid- to upper 80s by Tuesday and Wednesday," KSL Meteorologist Dan Pope said. "That is going to cause rivers and streams to rise, with some reaching or exceeding flood stage due to the hot weather."
A slight chance of rain Wednesday night and Thursday will compound the situation. "It's the worst thing that can happen: hot weather and heavy thunderstorms," Pope said.
If we get into the high 90s, he said there's going to be big flooding problems.
"The snow in the mountains is like a big time bomb waiting to go off," he explained, "and the high temperatures will set it off," leading to high runoff.
Shorter term, flood warnings for high river flows expired Friday for Lost Creek in Morgan County, the south fork of the Ogden River in Weber County, and the Weber River in Davis, Morgan, Summit and Weber counties. Flooding on the lower Weber County near the Great Salt Lake is not the result of high river flows as much as a levee that broke Thursday morning.
In Juab, Piute, Sanpete and Sevier counties, a flood warning for the Sevier River from Piute Reservoir to Yuba Lake expired Friday afternoon.
Moderate flooding is being reported on the Green River near Jensen in Uintah County and near Green River in Grand County. Minor flooding has been in the forecast for the Colorado River in Grand County near the Utah-Colorado state line.
The Utah Department of Transportation reports flooding on roadways may slow or close segments of state Route 128 in Grand County, state Route 100 in Millard County, state Route 16 in Rich County in the area of Wolf Creek, and state Route 118 in Sevier County, where the road Friday was closed at milepost 1.5 in Joseph due to flooding from the Sevier River.
UDOT reports it is still delaying the opening of several seasonal roads because of remaining mountain snowpack. Those include state Route 39 in Monte Cristo east of Ogden; state Route 65 in East Canyon northeast of Salt Lake City; state Route 190 in Guardsman Pass between Brighton and Park City; state Route 224 in Guardsman Pass between Park City and Midway; state Route 92, the American Fork Canyon/Alpine Loop; state Route 150, the Mirror Lake Highway between Kamas and the Wyoming border; state Route 35, the Wolf Creek Pass between Francis and Hanna; state Route 153, the Mount Holly Junction east of Beaver; and state Route 148, Cedar Breaks east of Cedar City.