A week of stormy weather propelled Montana snowpack numbers to average or above-average levels for river basins east of the Divide and added as many as 26 percentage points to a much weaker pack west of the Divide.
Snow that clogged Billings streets and made highways across the state treacherous during the holidays stacked up in even greater amounts in the mountains. Major gains improved the outlook for spring runoff after a dismal early start in northwestern Montana, where some basins were experiencing record low snowpack less than a week ago.
The numbers still aren't great in many of those Western Montana basins, but the snow keeps coming.
In the Lower Clark Fork Basin, snowpack jumped from 47 percent of normal on Dec. 23 to 71 percent of normal on Wednesday. The Bitterroot Basin went from 54 percent of average last week to 80 percent on Wednesday.
Most basins on the west side made gains of 19 to 20 percentage points.
The Jefferson, Madison and Missouri headwaters gained 14 percentage points, thrusting them into the average to above-average range. The Smith-Judith-Musselshell basins gained 10 percentage points and now boast a snowpack at 102 percent of normal.
The Yellowstone, which had been accumulating a moderate snowpack, also ends the year in good shape. Snowpack on the upper Yellowstone, which includes the stretch of the river from Yellowstone Park to its confluence with the Bighorn River near Custer, gained 11 percentage points and is now at 96 percent of average.
The lower Yellowstone, which includes the stretch from Custer to the confluence with the Missouri River, gained 9 points and stands at 95 percent of average.
Even with recent snows, the St. Mary and Milk River Basins are straggling. While storms pumped an additional 14 percentage points worth of snow in the mountains, the basin still reports just 61 percent of its average pack.
Snowpack in the Bear Paw Mountains that feed the Milk River is actually one of the best in the state, at 141 percent of average. But sites that feed the western stretch of the system are about half of normal. The Many Glacier Snotel on Wednesday recorded the pack at 59 percent of average.