Pacific Northwest 2024 Water Year Impacts Assessment Released
Extreme Heat, Snowpack Variability, and Drought Response Highlighted in Annual Report
The fifth Pacific Northwest Water Year Impacts Assessment, released today, presents a detailed examination of seasonal climate conditions across Washington, Oregon, and Idaho for the 2024 water year (October 1, 2023–September 30, 2024).
The Water Year Impacts Assessments are intended to summarize the water year conditions and sector impacts as a resource for future management of drought and other climate extremes. This particular assessment is the result of several annual Water Year Recap and Outlook meetings across the three states, alongside meeting discussions, distributed surveys, and the authors’ expertise.
“This year’s findings reinforce the importance of proactive planning and cross-sector collaboration to build climate resilience in the Pacific Northwest.” said Karin Bumbaco, Deputy State Climatologist. “By documenting how last year’s conditions translated into real-world consequences, this assessment can help communities prepare for and respond to abnormal weather conditions during future water years.”
Key Findings from the 2024 Water Year:
The 2024 water year was marked by above-normal temperatures, ranking as the fourth warmest on record in the Pacific Northwest across the 129-year record. Precipitation was near-normal in Oregon but slightly below-normal in Washington and Idaho. Drought conditions improved in western Washington and western Oregon but worsened in the inland Pacific Northwest.
Other main lessons learned from this past Water Year include:
1. Cooler, wetter spring weather helped lessen overall annual drought impacts.
Drought conditions in the Pacific Northwest would have been much worse if not for a few timely weather events. Specifically, May was cooler than normal, which provided additional snowfall accumulation in the mountains. The colder spring temperatures slowed snowmelt slightly, extending the availability of water later into the season. Then in mid- to late August, an unusually cool and rainy stretch helped increase streamflows and lower river temperatures—just when migrating salmon needed it most.
2. Temperature swings shaped water supply just as much as precipitation.
When we talk about drought, we often think of it in terms of rainfall (or the lack of it), but temperature also plays a major role in shaping our water availability. In 2024, extreme temperature shifts (like the unusually warm December and July, and the cooler-than-expected May) had major impacts, such as:
- December’s warmth meant little to no early snowpack.
- May’s cooler weather slowed snowmelt, which extended water supply.
- July’s heatwave led to an abrupt start to a record wildfire season in Oregon.
These examples show how temperature and precipitation work together in many different ways, making it tough to pinpoint exactly which factor caused each individual impact.
3. Communities took action to prepare for drought.
Rather than waiting for drought impacts to hit before reacting, many individuals and organizations at both the state and local level took proactive steps to reduce risks.
- In April, the Washington State Department of Ecology declared a drought emergency early. This happened after observing low snowpack in combination with the expectation of warmer and drier than normal conditions for spring and summer, which gave people more time to prepare compared to previous years.
- More than 65% of survey respondents in sectors like drinking water, agriculture, and recreation adjusted their operations in response to dry conditions.
- In the Dungeness Basin, the Jamestown S’Klallam Tribe partnered with state agencies, farmers, and nonprofits to support salmon migration—showing how collaboration across sectors can lead to real solutions.
These examples highlight the power of early action and the importance of working across sectors to tackle climate challenges.
4. The effects of past droughts still linger.
Even in places that didn’t experience drought last year, people still felt the long-term effects of previous dry years. The Deschutes Basin in Oregon is a perfect example. While 2024 saw near-normal snowpack and better reservoir storage, the region had been in drought from 2020 to 2023. This shows us that drought recovery takes time, and even one normal year doesn’t erase the lasting impacts of prolonged dry conditions.
This underscores another important point from this year’s assessment: drought isn’t just about a single dry year—it’s about the cumulative effects of conditions over time.
The Pacific Northwest Water Year Impacts Assessment is produced through a collaboration between the Washington State Climate Office, the Climate Impacts Group at the University of Washington, Oregon Climate Service, Idaho Department of Water Resources, and is funded by the NOAA National Integrated Drought Information System (NIDIS). The assessment integrates climate data, sector-specific surveys, and community-reported impacts to provide a holistic picture of how water year conditions influence the region.