Spokane set a daily record for rainfall on Thursday with 1.18 inches, more than double the previous record of 0.54 inches set in 2003.
A strong low pressure area with moisture feeding in from subtropical latitudes fueled waves of rain, including a heavy downpour around 5 p.m., which caused widespread flooding where catch basin grates were plugged and storm water systems overloaded.
Nearly a half inch of rain fell between 5 and 6 p.m. at Spokane International Airport.
Moderate to heavy rain fell across the Spokane area again about 10 a.m. today with some wet snow in the mix.
Across the region Thursday, rainfall amounts of a half an inch to an inch were common. However, Spokane had one of the higher amounts for lower elevation locations. Coeur d’Alene reported 0.95 inches on Thursday at a location near the lake.
A hazardous weather outlook was issued today for high flow on small streams and creeks in the region.
Latah Creek was flowing at 1,260 cubic feet per second at Spokane, about double its average flow for this time of year.
The Palouse River at Potlatch, Id., was flowing at 3,580 cfs due to rain and snow melt. That was more than five times normal for this time of year. Weather Service forecasters said it would remain below flood stage.
Other North Idaho rivers were rising, but not threatening to flood.
High avalanche danger was reported in the mountains of the region due to a series of snow storms and a stacking of layers of different consistencies, leading to poor bonding.
Rainfall this month is making up for a dry December, and the Spokane area gained an inch on what had been a precipitation deficit of about 2 inches. The Spokane area has had 8.76 of precipitation since Oct. 1, which is still an inch below normal.
However, March alone has had 1.8 inches compared with a normal through Thursday of 0.79.
Elsewhere, heavy snow on the west slopes of the Cascades led to closure this morning of the eastbound lanes of Interstate 90 ahead of the climb up to Snoqualmie Pass. The freeway reopened just after 8 a.m. Heavy snow and vehicle spinouts were reported.
Forecasters are calling for a 60 percent chance of rain this morning, changing to a snow or rain mix this afternoon. The snow level will drop to about 3,200 feet.
Rain is likely again on Saturday, but a partly sunny day is possible on Sunday as the series of storms this week clears the region.
Cooler temperatures are expected with overnight lows dropping from 35 tonight to below freezing on Saturday and Sunday nights. Highs will go from the middle 40s today and Saturday to the lower 40s on Sunday.