May 7 Snow2Flow update – with return of warm weather, rivers will rise again to generate another peak from remaining snow with temps pushing 80s F in Boise. Air temps and duration of warm spell will determine how fast the snow melts, how high the rivers rise and when the snow runs out that feeds the rives. Enjoy and be safe!
Low snow means low flows in these basins. Hopefully more weather moves in during the month of May
Here’s an update looking at remaining snow, snowmelt, volume forecasts and similar runoff years. We’ll see a decrease in melt and flows with cooler front moving in, but melt and flows are projected to rebound later this week with return to high pressure, that will hopefully move on sooner than later…
With below normal precipitation April 1-24 across the state and little expected in next 7 days, streamflow volumes are decreasing from April 1 release. The Owyhee River has peaked from snowmelt and remaining snow will help sustain flows. Remaining snow in Bruneau and Salmon Falls basins will produce another another flow increase. Future snowmelt rates and weather will determine if next flow increase exceeds the previous peaks already seen.
Remaining snow will help to sustain flows… how long – here are a few similar runoff volumes and recession years. With little weather on the horizon, current snow melt from warm days and freezing nights is ideal.
Current snow & water supply summary across the state with more details for Upper Snake, Boise and Payette basins.
Why they send river rejection emails out on Valentine’s Day, I’ll never know but got my rejectionS. For those wondering about the snow, here’s an update that show snow changes from Jan to Feb, chance for the pack to recover and SWE graphs of analog snow years for the lucky ones that won !
Early Bird Forecasts or are they called Outlooks – either way, you got to know when to hold them, know when to believe them, know when to walk away and know which areas are favored for more snow and why. There are lots of late summer/early fall Winter Outlooks being shared and passed around. Recently, it seems there is a race to see who releases the first Outlook. Here’s a summary about what I’ve been watching for a while. See if it helps or share what you watch and works for you. Don’t believe the first forecast you hear or until you hear the same forecast from 2 or 3 unrelated friends.
Read on for more info about SOI correlation with western rivers and how analog years are identified and used to help with predicting / monitoring this winter.
Analog years used for this winter (water years):
1956-57 is water year 1958
1964-65 is water year 1966
1971-72 is water year 1973
Another analysis shows this year’s El Nino initially was tracking 2009-10 El Nino winter. Next post: SWE plots of analog years and 2010 to how snow is tracking or not.
Snow Weather and Flow 