Spring 2019 River Flow Forecast
by Kyle Dittmer, CRITFC Hydrologist-Meteorologist
The spring snowmelt (or freshet) causes rising high-water levels in the Columbia River and its tributaries each year. This condition helps get salmon smolts downriver quickly, but also makes it dangerous for fishers. CRITFC monitors river conditions and forecasts during the year. We inform fishers of the predicted timing and nature of the freshet to help improve their river safety. Lower Columbia River flow came early this year. The normal peak should be May 20-31. The primary peak was April 25 or 30 days earlier than normal – driven by natural climate variability (El Niño events) and long-term climate change. A secondary peak will occur by June 1.
The NOAA-National Weather Service May 1 river spring-summer forecast for the Columbia River at The Dalles is at 94% of normal. This winter’s weather was highly variable. A very cold and snowy February help recover snowfall lost earlier in the season. NOAA recently declared that we are in a weak El Niño event – which means we will likely see higher temperatures and drier conditions during this spring-summer. River conditions will be near normal this spring for juvenile salmon migrating out to the ocean and for returning adults but lower water levels and more forest fires this summer are now more likely. Ocean conditions are expected to be neutral-to-poor in 2019 for salmon survival.
Current Columbia basin snowpack accumulation: Washington Cascades 50 – 90% of normal, Oregon Cascades 50 – 75% of normal, Lower Snake 90 – 150%, Clearwater 90 – 125% of normal, southern Idaho 90 – 125% of normal. Current snow levels are about 5000 feet.