Areas in bright green indicate where flood warnings or advisories are currently in effect in the West. (National Weather Service)

In the wake of historic flooding along parts of the Missouri River, flood warnings or advisories have also been issued in several western states, including Wyoming, Idaho, Montana, and Nevada. In Montana, rising waters in the Yellowstone River have hampered clean-up efforts after an oil pipeline burst there a week ago.

Yosemite’s Bridal Veil Falls after a season of normal snowfall (By author)

Beneficial effects

While the rapid snowmelt has proved hazardous to some areas, the lingering snowpack has been welcome news to cities across the Southwest. According to the Associated Press, melting snows in Wyoming, Utah and Colorado are flowing into the Colorado River Basin and replenishing crucial water supplies in Arizona, Nevada, and Southern California.

Precipitation relative to average across the contiguous U.S. December through May with rankings. (NOAA)

How much snow is left?

Even after weeks of substantial melting, last winter’s historic snowfall across the Rockies means the summer sun still has some work to do. Weekly reports published by the USDA’s Natural Resources Conservation Service indicate that many high elevations still have significant amounts of snow this late in the season. Just two weeks ago, snowpack measurements on the Olympic Peninsula in Washington were 39,100 percent of normal (or nearly 400 times the average for this time of year).

Fourth of July skiers, some wearing shorts, at Lake Tahoe. (Associated Press)

For D.C. and most of the country, however, snow was simply not on the Fourth of July agenda.