Near the end of April 2020, weekly storms had blanketed much of the state with rain and snow. Precipitation, it seemed, would be plentiful. Grasses would grow. Small plants and shrubs would leaf and bloom. Wildlife and livestock would have food and water.
Then that comforting precipitation stopped. By the end of summer, soil moisture content in portions of central and eastern Wyoming hovered in the tenth percentile. Wildfires raged, one burning the most acres in recent history. Areas of Fremont and Natrona county were in what’s classified as extreme drought. Months later in the depth of winter, the forecast hasn’t really improved.
“For the bulk of the state, the outlook is the drought will persist,” said Chris Jones, a meteorologist with the National Weather Service in Riverton. “I don’t see us getting relief, at least if we take a look at three month as a whole.”
The snow water equivalent in much of Wyoming hangs between 65 to 75 percent of median. One SNOTEL site — the instruments used to gauge how much water is contained in snowfall — listed the Cheyenne area as 16% of normal on Monday. While that reading doesn’t completely reflect the region, it does, combined with information from SNOTEL sites around the state, paint a concerning picture, said Tony Bergantino, acting director for the Water Resources Data System and the Wyoming State Climate Office.
“Our big snows come in late February, March and April, and we can really turn things around,” Bergantino said. “Or it can break us if we don’t get early spring and late winter snows.”
Like many of us, wildlife biologists and ranchers are hoping for the best and bracing for the worst.
Trending toward dry
Dozens of SNOTEL sensors dot the state, mostly in high mountain areas, and report a number each day to a data center in Portland that interprets the information and offers up snow reports. As of Wednesday, the only place this year approaching normal was Yellowstone, which sat at 96%. The Shoshone basin was 89% and Tongue was 88%. The Wind River Basin, on the other hand, was 69%, Sweetwater was 59% and Lower North Platte was 66%.
“It’s one thing coming off a year with good precipitation and soil moisture,” Bergantino said. “It’s another thing when you have soil moisture depleted.”
The last time conditions were this dry was 2012 to 2013. That drought was arguably worse than this has been so far, but it was also a season noted for grass that stopped growing just after it started, ranchers were forced to sell off portions of their herds and fires that raged across the state, with more than 1,300 fires burning about 600,000 acres.
Before that was the early 2000s when multiple years of sustained drought parched the state.
It isn’t quite February, however, and much of Wyoming’s precipitation arrives as wet storms in late winter.
But Jones cautions that according to the most recent drought outlook, those storms may never arrive, at least not consistently.
A La Nina pattern — which is what the U.S. is experiencing this year — typically dumps precipitation on the Pacific northwest and northern Rocky Mountains, but even those areas haven’t been doing as well as they would normally. For central, eastern and southern Wyoming, a La Nina often brings equal chances for drier, warmer, windier conditions. But this year we have seen little snow and high wind which often brings warmer temperatures.
The 90-day forecast predicts those same warmer and drier conditions until the end of April for much of Wyoming. For April, May and June, the northern portion of the state has an equal chance of below, average or above normal precipitation, but the southern portion will likely still be below normal, Jones said.
“For the second year in a row, late summer, so July, August, September, is not showing a good monsoon, which is where we get our summer precipitation,” he said. “If you’re looking for us to get some drought relief, the outlook isn’t particularly good.”
Impacts of drought
What this means for wildlife is a little early to tell, said some Wyoming Game and Fish Department biologists.
Pronghorn in central and southeastern Wyoming had already been suffering from a relatively hard winter followed by drought. Populations like the Medicine Bow herd in the Shirley Basin area went from estimates of 72,000 animals in 2015 to 52,000 in 2019, said Lee Knox, a Game and Fish wildlife biologist in Laramie.
Another sustained drought could prove to be devastating, causing females to ween their young early and dropping survival rates for many of the fawns born this year.
But on the other hand, a mild winter can be a blessing to Wyoming’s herds. The worst would have been a severe winter coming off of 2020’s drought, said Justin Binfet, Casper’s regional wildlife coordinator. If the mild winter persists, overwinter survival of adults can help offset last year’s fawn loss, but eventually, he said, the state will need moisture.
Wyoming’s livestock producers, Jim Magagna, executive vice president of the Wyoming Stock Growers Association, are growing nervous.
Most Cowboy State ranchers have been around for generations, surviving the cycles of drought and floods, and so most are already beginning to think about another dry year. For some it could mean considering selling off portions of their herds. For others it could mean not bringing as many animals to their pasture. If it’s bad enough, government programs through the U.S. Department of Agriculture can help.
“It’s a serious concern right now,” Magagna said. “But not a panic.”
One bright spot is the possibility for a few large spring storms that dump either wet snow or rain, and those are tougher for meteorologists to predict in a long-term forecast, Jones said.
Fortunes can change quickly, the wildlife biologists and Magagna acknowledged, on Wyoming’s mountains and high plains.