Idaho saw strong wind, rain Wednesday — but only for some. Here’s where it was worst
On Wednesday afternoon, the Treasure Valley braced for severe thunderstorms, strong winds and pouring rain. Fears of damaging weather were so high that Idaho Power sent a rare warning to customers, asking them to “prepare in case of wind-related outages.”
The warning was warranted. Idaho Power confirmed to the Idaho Statesman that Treasure Valley residents lost power as a result of the wild weather but could not confirm how many. The utility also preemptively shut off power to some residents on Wednesday to mitigate any chance of wildfires — at one point, Idaho Power’s outage map showed more than 8,000 customers without electricity.
However, strong storm expectations did not come to fruition in other parts of the Treasure Valley, such as downtown Boise. National Weather Service meteorologist Michael Cantin told the Statesman that one severe thunderstorm tracked near the downtown area, but it was short-lived and isolated.
So where did the storms hit?
Where were the storms the strongest?
On Wednesday, the Weather Service recorded approximately 2,800 lightning strikes across eastern Oregon and Southwest Idaho. Since records began in 2000, that amounted to the 38th-highest number of strikes recorded in a single day for the region and the ninth-most for a day in July.
However, most of those lightning strikes occurred in Oregon and along the state line near Ontario.
“I think part of what led the storms around us is the terrain,” Cantin said.
Because of high temperatures and moisture from the southwest flowing toward Boise — in conjunction with a low-pressure system moving in off the West Coast — the atmosphere around Idaho is particularly unstable and ripe for thunderstorm formation. On Tuesday, smoke from the Durkee Fire in eastern Oregon formed pyrocumulus clouds and rain ash in the western Treasure Valley.
The unstable atmosphere allowed storms to pop up everywhere, Cantin said, but the storms were especially strong west of the Boise-Meridian-Nampa corridor because of the flatter terrain in Oregon.
“They kind of fired up (in eastern Oregon) and then worked their way to the north and the east,” Cantin said.
“Sometimes when we get these southwesterly flows when the winds move north and east of the Owyhee Mountains, sometimes they can suppress or lessen the lift in the storm,” Cantin continued. “So you end up with fewer storms to jump directly to the northeast of the mountains.”
After the first round of storms moved through the area early Wednesday evening, a second round flared up shortly before midnight. The storms packed 40 mph wind and pea-sized hail, according to the Weather Service, but once again started in Oregon and tracked northwest of Boise.
Highest reports of wind and rain
The Weather Service is still receiving reports from Wednesday’s storms. As of Thursday morning, Cantin said the highest rain measurement recorded in Boise was only around one-tenth of an inch.
Areas closer to the Idaho-Oregon state line reported up to a quarter of an inch.
Although one-tenth of an inch is not a lot, it was the first time Boise recorded that much rainfall since 0.4 inches fell on June 3.
The strongest wind recorded in Ada County was on the Crestline trail just north of Military Reserve. A wind gust of 59 mph was recorded at a measurement site along the trail, Cantin said.
The National Weather Service also reported structural damage to a building in Parma, but the extent of the damage was not included.
