Seattle rainfall grows more intense with climate change
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Seattle's rainfall really is more intense than it used to be.
Why it matters: The increased rainfall intensity in Seattle and other U.S. cities is a symptom of human-driven climate change, bringing with it increased risks of flooding and landslides, according to a report from the nonprofit Climate Central.
By the numbers: Hourly rainfall intensity increased between 1970 and 2024 in nearly 90% of the 144 locations analyzed, per Climate Central's report.
- Among the cities with an increase, hourly rainfall intensity rose by an average of 15%.
Zoom in: In Seattle, rainfall intensity increased by about 6% between 1970 and 2024, the report found.
How it works: The researchers divided each location's total annual rainfall by its total hours of annual rainfall, using NOAA weather station data.
- That approach quantifies how much rain fell for each hour it was raining in a given year — in other words, rainfall intensity.
Between the lines: Human-driven climate change is resulting in warmer air, which holds more moisture and thus can drive more intense precipitation.