NDMC reviews 2017 as a year of western improvement, Northern Plains drought
The year from Jan. 1, 2017 to Dec. 31 saw major changes for the U.S. in terms of drought, but the associated harsh weather conditions, including wildfire and flooding, also impacted communities across the U.S.
In their Annual Climate Summary, the National Drought Mitigation Center (NDMC) reported the beginning of 2017 showed an easing drought in California, but the end of 2017 brought an evident La Niña impact in the southern U.S. in the form of drought development across the Southwest, Southern Plains and Southeast.
“Climatologically, it was the third warmest year on record for the United States and the 20th wettest year,” said NDMC Climatologist Brian Fuchs. “Almost every state had a top-10 warmest year on record.”
Dry conditions
At the end of 2017, 23.18 percent of the country was in drought, an increase from just 18.83 percent of the country started the year in drought.
While drought overall increased, severe drought in the U.S. dropped from 7.21 percent of the country to 6.24 percent of the country, and extreme drought improved from 2.63 to 0.69 percent.
“December ended with 62 million people affected by drought, which was more than double the number from the beginning of October, when 31 million people were affected,” Fuchs reported.
While the Plains and South were very wet in terms of precipitation in October, the water year for western states started off slowly.
“Areas such as the northern Rocky Mountains and Great Lakes region were wet during the last quarter of 2017, though,” Fuchs said, noting some areas had moisture that was four inches above normal precipitation.
At the same time, most of the U.S. recorded normal to above-normal temperatures.
“The seasonal drought outlook has much of the drought over the southwest United States persisting and continuing to develop through the end of May,” he commented. “Improvements to the drought situation are likely over the Northern Plains and Midwest.”
Impacts
As dryness developed during May in the Dakotas and Montana, Denise Gutzmer, NDMC impact specialist, noted high numbers of cattle were sold, along with slowed pasture and hay growth.
In addition to challenges associated with livestock feeding, Gutzmer noted, “Numerous wildfires raged in Montana, sparked largely by hundreds of lightning strikes in early July.”
“By the end of August, more than 1,500 fires burned nearly 600,000 acres, or 937 square miles,” she added. “About that time, a lightning storm that offered little rain sparked another 45 fires, as much of the state was in moderate to exceptional drought and was primed to burn.”
By the end of September, 1.2 million acres had burned in Montana.
Water year
California saw a slow start to its wet season, with the first on-the-ground snow survey at one site in the Sierra Nevada Mountains revealing only three percent of normal snowpack.
At the same time, Gutzner summarized impacts in Colorado as a result of lack of snow.
“The lack of snow in Colorado alarmed ski resort operators, who expected to have plenty of powder to entertain their visitors over the Christmas break,” Gutzmer said. “Instead, trails remained bare.”
Volunteer weather observers in Colorado reported plants going dormant in September for lack of moisture, and in December, snow totals averaged as little as 20 percent of normal in parts of the Colorado River Basin, which leading to a foreboding sense for the coming year.
“The National Weather Service’s Colorado River Forecast Center predicted the river would flow at about 54 percent of its average volume during the key runoff period from April to July,” Gutzmer noted. “Snowpack could still improve, as it typically accumulates through March.”
Saige Albert, managing editor of the Wyoming Livestock Roundup, compiled this article from NDMC’s Winter 2018 edition of “Droughtscape.” Send comments on this article to roundup@wylr.net.