Correction: The National Weather Service originally reported 1.22 inches total rain fall on Wednesday. That was a calculation error on their part. Their corrected number is .62 inches.
A thunderstorm deluged Boise with rain Wednesday evening, dropping more than an inch of precipitation in some areas and flooding streets, parking areas and buildings, the National Weather Service and Ada County dispatch said.
Showers are moving north through Owyhee County at about 15 mph Thursday afternoon, a National Weather Service meteorologist said.
The Treasure Valley may experience heavy rain and strong winds tonight, between about 5 p.m. and sunset. There may also be light showers overnight. Wind gusts could be 40 to 50 mph.
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“We have a pretty stormy forecast in store for (Thursday) and (Friday),” Valerie Mills said earlier Thursday.
Boise recorded getting 1.22 inches of rain Wednesday, blowing the last record for July 8 of .10 inches out of the water. This makes it tied for the third wettest day during summer. The showers were notable for their abruptness as well. More than half an inch fell within 7 minutes, according to the National Weather Service.
Since 1878, an inch or more of rain in the summer has happened about 8 times, Mills said.
“It’s pretty rare for it to occur at this climate site,” she said.
The storm headed west through Meridian and Eagle and then into Canyon County, but the amount of precipitation declined as the storm moved west, meteorologist Dave Groenert said. Rainfall at the weather service’s Boise Airport office was measured at 0.6 inches, he said, and the amounts varied widely across town.
The storm caused flooding and even shut down a Boise Open pro-am four holes early. The golf tournament, which started Thursday, has only been delayed once because of rain or lightning. That happened in 2011, when play was held off for almost two hours because of thunderstorms.
Dispatchers and emergency crews were “crazy busy” fielding calls from about 6 p.m. to about 7:30 p.m., an Ada County dispatcher said. Most of the calls concerned street and parking lot flooding, with some callers reporting water getting into their homes or businesses, she said.
“The rain rates were enough that some areas couldn’t handle the runoff from the rain, so you saw urban flooding,” Mills said.
Winds with gusts as high as 46 mph complicated the situation, Groenert said, and the dispatcher said some trees and utility lines were blown down.
Rain and thunderstorms are likely to continue Thursday and through Saturday, Groenert said, citing a “slow-moving system.”
The high Thursday could be around 89 degrees, with a low of 64 degrees. Friday could see a cool down with a high of 83 degrees and a low of 61 degrees, according to the National Weather Service.