MTPR

Montana's Water Supply Looks Good Heading Into June

Jun 5, 2019

Montana’s latest water supply outlook forecast is in and paints a fairly encouraging picture. 

The Bozeman-based Natural Resources Conservation Service says the water supply in most Montana basins is in pretty good shape as we head into the hot summer months.

“We had a snowpack which was near to above-normal in most areas, and precipitation was near to above average. I think we landed right about where we needed to be,” NRCS Water Supply Specialist Lucas Zukiewicz said. 

Zukiewicz says it’s too soon to make any firm predictions about summer steamflows across Montana.

“I think we have a couple of months which are pretty important — specifically June," Zukiewicz said. "We want to see what June precipitation totals do, because they typically supplement that water that we already have in the rivers from snowmelt. We’re going to watch the month of June because that will help dictate what things look like later in the summer, but overall I think we made up ground where we needed to.”

Late May brought plenty of rain to parts of eastern Montana, including the Sun-Teton-Marias river basins.

“But the Smith-Judith-Mussellshell, Upper Yellowstone, the east side of the Absaroka Range, really got a healthy amount of precipitation and it made up a lot of ground in some areas which were particularly dry, especially in that Sun-Teton-Marias area,” Zukiewicz said. 

Water year-to-date precipitation, basin percentage of normal, June 1, 2019.
Credit NRCS Montana Snow Survey Staff / USDA

West of the divide above Missoula, the precipitation and remaining snowpack are at average to slightly above average levels for this time of year.

“Snowpack’s been in good shape. It’s much better than last year when we were warning of too much snow," Zukiewicz said. "We have a little bit above normal this year and I think that’s great news.”

Northwest Montana, however, is particularly dry; a trend that started last summer.

“We had precipitation which was well below average for [May]. And May and June are our last two months to get that precipitation before we move into that more convective thunderstorm type activity that we get through our summers," Zukiewicz said. "We might be able to make up ground in June. We’re just keeping an eye on it. It has been particularly dry.”

Zukiewicz says reservoir storage across Montana is near to above average. He credits water managers with doing a great job of preparing for this summer. He describes the winter of 2018/2019 as both erratic and fascinating.

“I think a lot of the predictions for an overall pattern never really played out," Zukiewicz said. "We would change those every month and think that it was going to be dry and it ended up being wet. We’d think it was going to be cold and it ended up being warm. It was really interesting to see the backs and forths we had this winter.” 

The NRCS’s June Water Supply Outlook Report will be the final report for the 2019 season and will resume next winter.