Graupel storm tests Inland Northwest motorists, foreshadows wintry weather ahead

All is well: The “weather bomb” didn’t drop.

As some meteorologists had warned, what’s referred to as a “bomb cyclogenesis” – a fast drop in air pressure that results in destructive weather – did not wreak havoc Sunday on the Inland Northwest.

Instead, the winter season’s first graupel storm hit Sunday afternoon, lasted about two hours and turned out to be a minor inconvenience for motorists.

The soft hail and snow pellets – in addition to rain and regular snow – began falling in the area about 1 p.m. and subsided in most areas around Spokane about 3:30 p.m. Heavy gusts pushed the pellets at speeds upward of 35 mph, as recorded at Spokane International Airport. Parts of Spokane Valley and Stateline also reported thunderstorms.

National Weather Service forecasters estimate only about two- to three-tenths of an inch of graupel fell. By Sunday evening, traffic seemed mostly unaffected as most of the snow quickly turned to slush.

But forecasters warn the moisture left on the roads could spell disaster for commuters Monday as temperatures fall toward the teens, with nighttime lows remaining there through most of the week.

“The Spokane area is going to struggle to reach even 20 degrees,” said Joey Clevenger, a Spokane-based National Weather Service meteorologist. “One of the main points for us is that the icy roads for tomorrow morning will be bad.”

The harsh weather is expected to continue through the week as snow is forecast to pelt the Inland Northwest and much of Eastern Washington starting Thursday.