Flash floods, thunderstorms join PNW’s erratic streak of weather
May 15, 2023, 3:04 PM
After the Pacific Northwest’s record-breaking bout with the heat occurred last weekend, a flash flood warning for most of the Cascade foothills has been authorized as thunderstorms are forecast to roll through. The warning is in effect from 3 p.m. until 10 p.m. Monday.
“A significant amount of moisture combined with slow-moving thunderstorms may result in localized heavy rain with flash flooding in portions of Central and Eastern Oregon, and along the Washington Cascades this afternoon and evening,” the National Weather Service’s (NWS) warning read. “Primary concerns reside near recent burn scars from wildfires over the past two to three years.”
NWS reported the isolated storms may bring heavy downpours that could combine with snow melt. Winds reaching 40 mph and a half-inch of hail were included in its alert.
“Gusty winds could knock down tree limbs and blow around unsecured objects,” the alert read. “Minor damage to outdoor objects is possible.”
Cliff Mass on Seattle heatwave: ‘It won’t be like 2021’
Climate Central analyzed data from the National Oceanic and Atmospheric Administration, according to KING 5, which produced a study showing increased thunderstorm potential across nearly the whole state of Washington with a more drastic upward shift around the region. Two weeks ago, a flurry of lightning strikes already lit up the night skies in the Puget Sound area.
“These thunderstorms we’re going to have late in the day today have a chance to be more like Midwest thunderstorms and not the usual kind of wimpy ones we have here,” Meteorologist Dana Felton said.
The flood warning came promptly as the region dealt with record-breaking heat. The West Coast, from Seattle and Portland all the way to central California, experienced an early season, summer-like heat wave. Mother’s Day broke the record for the hottest May 14 in the Puget Sound region with an 89-degree day, a record initially set in 2018. The hottest May 13 also occurred (86 degrees), breaking another record from 2018.
The average high for Seattle in the month of May is 66, according to The Seattle Times. The heatwave is expected to linger through most of the week. Cooling stations — including the Jefferson Day Center with Salvation Army, Compass Day Center, and Seattle Indian Center — have been implemented for the dangerous heat, with libraries in King and Pierce counties also open as a place to cool down.
Authorities also urged people to be wary of cold water temperatures should they be tempted to take a river or lake swim to cool off. Officials often see a rise in drowning calls when the temperatures rise.
Cold water remains dangerous despite Seattle heatwave
In addition to the region’s erratic weather of late, thunderstorms can even bring wind events that pick up dust from agricultural fields in the state’s rural areas, creating dust storms — something University of Washington meteorologist Cliff Mass believes the state could be in store for.
“There’s one unusual thing that may happen, the winds may pick up in eastern Washington over the weekend, and we may even see a dust storm there, so that’s something to look forward to,” Mass told Jason Rantz on KTTH 770 AM. “That’s kind of an unusual event that I think we might see.”
According to the state’s Department of Ecology, dust storms typically occur at the end of March and the beginning of April.