REGIONAL— Drought conditions are continuing to expand in Minnesota. That’s according to the latest map from the U.S. Drought Monitor, which shows nearly half of the state, and all of the northeastern third of Minnesota, in severe drought.
If one needed any other evidence, it can be found in stream flows across north-central and northeastern Minnesota, where the entire Rainy River basin is below what is known as Q90.
It’s a hydrologists term, where Q stands for quantity and 90 indicates that the quantity of stream flow is higher 90 percent of the time during that same time of year. Stream flows in northeastern Minnesota are typically at their lowest point of the summer in August, but this year the flows are much lower than usual.
In the Vermilion River, a mid-range flow for August is about 350 gallons per second, or gps. As of Monday, however, the flow was down to 83 gps, well below the annual Q90 of 121 gps. It’s the same story with the Little Fork, Basswood, and Rainy rivers, as well as the St. Louis River, which is part of the Lake Superior watershed.
If it seems like this is a story that has been repeating itself in recent years, credit your recollection as accurate. According to state climatologist Kenny Blumenfeld, Minnesota has been in an extended pattern of more frequent drought, dating back to about 2020.
“It is definitely part of Minnesota’s climate, precipitation goes up and down, but in general, have seen more incidents of drought,” said Blumenfeld. “It’s hard to know if it’s connected to climate change.”
While we typically think of drought as governed by precipitation, Blumenfeld notes that it’s a combination of precipitation and temperature that ultimately determines the depth of drought. “Our wet periods are wetter than they used to be, and our dry periods are also wetter than they used to be,” said Blumenfeld, noting that the state is generally receiving more precipitation (particularly rainfall) than in the past.
“That said, other things are going on,” he added. That includes warming temperatures, which increase the speed at which the landscape dries. “Northern Minnesota is the fastest warming part of the state, and that can increase the speed with which drought can set in.”
The extraordinary heat the region experienced in July, when temperatures topped 100 degrees in areas along the Minnesota-Ontario border, quickly shifted the region into drought. “Nothing will speed up a drought like a few really hot days,” said Blumenfeld. “During that heat wave, northern Minnesota was the hottest part of the state. The air temps on the Canadian border were higher than on our border with Mexico.”
Looking ahead
In the relative short-term, there is little indication of major relief to the dry conditions. The 6-10 day forecast points to seasonal temperatures and rainfall, although the 8-14 day outlook suggests warmer than usual temperatures and below normal precipitation. In the longer term, Blumenfeld said the developing strong or “super” el Niño current in the Pacific Ocean portends a higher likelihood of a warmer and drier winter for Minnesota this coming season.
“Historically, those el Niños that are very strong, do have a noticeable impact on winter weather,” said Blumenfeld. “Generally, winters under those conditions are about five degrees warmer for the whole winter than normal. Even so, he said it would be premature to predict a winter similar to what was experienced in the winter of 23-24, when the region saw only a few weeks of snow cover in January and early February.
Typically, Minnesota experiences about 10-25 percent less snow during an el Niño winter than is normal, according to Blumenfeld. Less snow, and shorter periods of snow cover, mean both less recharge of soil moisture in spring and more opportunity for soils to dry out due to drying winter winds.