WYOMING – Maybe we are a tad spoiled around here. Blame it on Teton entitlement when it comes to bragging on powder, or last year’s winter that set the bar at “blizzard.” But it sure doesn’t feel like a winter in Jackson this year. At least not down low on the valley floor.
What will it mean for spring? The Wyoming Hydrologic Report for February 2018 is out and it takes an early look at how spring is shaping up across the state. Some of it may seem counter-intuitive as our snow shovels gather cobwebs in the garage and the back deck has been clear since Christmas.
Key hydrological ingredients for Water Year 2018:
- Above normal snow water equivalents (SWEs) in central through western Wyoming in early February.
- Above average soil moisture across basins in the north central through northwestern Wyoming.
- Above normal base flows into late fall 2017 along rivers and creeks in central to western Wyoming.
- Reservoir storages across Wyoming are averaging 100-105 percent.
- Above average snowmelt runoff volumes (water supply) expected across north central through northwestern Wyoming.
The news is good for irrigators, ranchers, farmers and others hoping for water to flow from the mountains through at least early summer. But it sure doesn’t stack up with 2017.
According to Wyoming NOAA hydrologist Jim Fahey, SWEs in the snowpack between 8,500 and 10,000 feet in early February 2018 are much lower for many basins that experienced record SWEs in 2017. However, SWEs are trending above normal in several basins to include the Upper Wind, Shoshone, and Snake Headwater Basins. Drainages along the western Big Horn Mountains also have above average SWEs for this time of the year.
Although it is too early to make definitive predictions on the magnitude of the upcoming runoff, several key hydrological ingredients should cause above average runoff volumes across north central through northwestern Wyoming.
Note: The magnitude of the spring and early summer runoff is highly dependent on the amount of moisture that Wyoming receives during the late March through early June time frame—especially for basins east of the continental divide.