For the third-straight month, Seatac experienced well below normal precipitation. 1.66 inches fell in December,  0.29″ shy of the record driest December on record (1978), and 31% of the 30-year normal of 5.35 inches. Much of the state, including parts of Seattle dipped below  25%.

The greatest 24-hour rainfall total of the month occurred on the 22nd when 0.51 inches fell. There were 0 days with greater than an inch, 0 days with with greater than 0.50″, 6 days above 0.10″, and 14 above 0.01″, each well below normal for the month. “Heavy rain” was not reported once, “rain” on only 1 day, and “light rain” on 15 days.

References:
AHPS montly precipitation image
SPU Climate Change program
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