Snowpack in Northwest Montana took a hit during April, a month in which high temperatures in Kalispell averaged 8 degrees above normal, driving record melting in some mountain areas.
The Natural Resources Conservation Service predicts lower-than-average stream flows this year, but expects rivers and streams to run higher than in 2015, an exceptionally dry year in Northwest Montana.
The conservation service’s monthly report released Thursday anticipates 88 to 89 percent of normal flows on the main stem of the Flathead River through September. Last year’s flows were 56 percent of normal.
For the Kootenai, that prediction is 92 to 93 percent.
As of Friday, the Flathead drainage’s mountain snowpack was 71 percent of normal, according to high-elevation snowpack monitoring sites. The Kootenai basin had dropped to 56 percent of normal, with mid-elevation snow completely melted at some sites.
The report noted that peak snowmelt had arrived one to two weeks ahead of normal west of the Continental Divide, and several sites in Northwest Montana broke records for total snowmelt last month.
Water watchers typically take stock of the resource in terms of the “water year” starting Sept. 1, when precipitation begins to accumulate as snow and ice in the upper elevations.
Lucas Zukiewicz, a water supply specialist for the conservation service, said this water year’s accumulation and runoff has been a significant improvement over 2015.
“Snowpack peaked really early last year and was basically just in maintenance mode from March on,” he said. “In the grand scheme of runoff, there’s more snow runoff than last year. We still have two months of summer precipitation to come, and it looks like our weather patterns are finally going to change a little for us, which is great.”
The El Nino weather system that delivered one of the region’s all-time driest spring and summer periods in 2015 is tapering off, and Zukiewicz said the models currently predict a return to normal by summer, followed by a transition to a La Nina pattern by winter. La Nina happens when the Pacific Ocean experiences a cooling trend, typically after warming up during an El Nino period.
Zukiewicz added that the weather pattern tends to bring cooler weather and more snow to the region.
April 2016 had the third-highest average temperature in Kalispell — 49.3 degrees, or 5.6 degrees above normal — since the National Weather Service began keeping records in 1899.
The average maximum temperature in April was 64.1 degrees, beating out a record set in 1934. On average, April’s high temperatures were 8 degrees above normal.
Two single-day temperature records were set last month: April 3 reached 70 degrees and April 9 reached 76 degrees, smashing the long-standing record of 71 degrees set in 1925.
Zukiewicz said those warm, sunny trends extended beyond the valleys, particularly in the mountains east of the Flathead.
“The northern Swan Range and Mission Range saw very high melt rates for the month of April,” he said. “Those Northwest basins were the ones that saw the most continuous melt throughout the month, and the biggest losses in terms of snow water.”
For the full report, visit www.nrcs.usda.gov/wps/portal/nrcs/main/mt/snow/waterproducts/basin.
Reporter Sam Wilson can be reached at 758-4407 or by email at email@example.com.