Damage to crops, structures, vehicles and homes were sustained last Friday during a flash flood and hail storm just after noon.
Flash flood warnings were in place for several days before Friday, July 20, and at around 12:30 p.m. the National Weather Service issued a severe storm warning for east Yakima County.
Motorists trying to travel on SR-241 were also halted by the weather.
The Washington State Patrol communication department confirms the rainfall was heavy enough to carry a car-sized boulder onto the roadway on SR-241 near milepost 18. The state patrol office issued a release closing the roadway from milepost 12 to 18, just four miles north of Sunnyside at 2:25 p.m., due to large amounts of water over the roadway. The road was reopened at 6:54 p.m.
Assistant meteorologist Ann Adams at the National Weather Service in Pendleton, Ore. says the storm seemed to center itself through downtown Sunnyside, though there were reports of hail and rain all throughout the valley.
Adams says a couple of cooperative weather observers estimated the hail that barreled down in and around Sunnyside to be around 1.25 inches in diameter, or the size of ping pong balls. A Sunnyside area resident, however, photographed a hail stone that measured up to the size of a golf ball. The observers also measured about a third of an inch of rain on Saturday morning.
Adams added that the number of storms for the summer season isn't uncommon to see.
"It's not common, but it's not uncommon," she said.
Weather predictions for the coming week include slightly lower temperatures than usual this time of year, and not much precipitation.
Towards the end of the month and through August, Adams says the weather service predicts normal summer heat, with spurts of warmer days.
"Besides the occasional thunderstorm, the weather seems to be pretty normal," she said.
Though the weather service can't predict the number of storms the area might see in the next few weeks, Adams says it's not uncommon to see storms during the summer months.
"You just so happened to have a whopper on Friday," Adams said.