By Kyle Dittmer, CRITFC Hydrologist-Meteorologist
Rising rivers due to snowmelt is one of many signs that spring is here. The normal pattern of rising spring river levels is a cue to salmon smolts to move downriver as fast as possible which helps ensure a safer passage route out to the ocean.
This winter had an El Niño event in the tropical Pacific Ocean, which tends to deliver warm, dry winters to the Pacific Northwest. After seeing many blasts of mountain snowfall from January through March, conditions have been drying during April-May.
Current snow-lines are at 4500 feet. The snowpacks in the Oregon Cascades and southern Idaho did improve in the last 12 weeks. The mountain snowpacks just reached their peak of the season. Temperatures are slowly warming up to start the mountain snowmelt process.
Snow data provided by NOAA/National Weather Service/Northwest River Forecast Center.
The latest NOAA/National Weather Service forecast suggests that tributary rivers are rising fast now and will peak on May 15-19. The mainstem Columbia and Snake rivers will peak in early June. Tribal fishers need to be aware of the danger of fast-moving water during these seasonal peaks and take appropriate safety precautions.
Chart data provided by NOAA/National Weather Service/Northwest River Forecast Center.