Thunderstorms headed to Boise with wind gusts, hail. How long will showers last?
Thunderstorms are rolling through Idaho during the final week of May.
Two significant systems are expected to merge over Southwest and south-central Idaho, according to Jerry Wang, a meteorologist at the National Weather Service office in Boise.
“This storm system is a closed low-pressure system that’s hanging off just south of us (Boise) over the Great Basin,” Wang told the Idaho Statesman during a phone call. “It’s slowly trekking northward, and it’s expected to become merged with an incoming Pacific storm system that’s slowly moving in toward the end of the week.”
Rain began on Tuesday, May 26.
Scattered thunderstorms were slated to deliver downpours and wind gusts on Wednesday, May 27, according to Wang.
The chance for storms will drop on Thursday, May 28, before there’s another increase in activity on Friday, May 29.
Over the weekend, Wang said, storms will gradually move into the south-central mountain ranges before they’re expected to clear out entirely.
Here’s what to know about the forecast:
How much rain has Boise received so far, was there lightning?
Only six-hundredths of an inch of rain fell across Boise on Tuesday, Wang said.
Ada County had only two recorded lightning strikes, according to the meteorologist. However, the National Weather Service reported high numbers of lightning strikes elsewhere in Idaho.
“Storms yesterday produced a lot of lightning in Southwest Idaho,” the Weather Service said in a post on X Wednesday morning. “Gooding County had 448 observed strikes, which is the most strikes recorded in that county of any day going back to the year 2000.”
How long will the storms last?
According to the seven-day forecast, there was a 30% chance of thunderstorms Wednesday afternoon.
High temperatures for Wednesday were forecast to hit 85 degrees before dropping to 55 overnight. The chance for scattered showers also drops to 20% overnight
Thursday was forecast to be mostly sunny after clouds linger throughout the morning. Highs on Thursday should reach near 87 and overnight lows are expected to be around 54.
“Thursday afternoon generally (has) a 10% to 20% chance of thunder across most of the Treasure Valley,” Wang said.
Thunderstorms return Friday afternoon, and chances for showers increase as the day goes on.
The high on Friday is forecast to be 80 with an overnight low of 51.
A chance for showers remains at 30% for Saturday morning, and storms are expected to move out of Boise by noon.
High temperatures for the weekend are in the 70s and with overnight lows expected around 49 degrees
What are the best ways to prepare for the storm?
Heavy downpours, gusts of up to 60 mph and small hail are especially a concern for Boise residents on Tuesday, according to Wang.
“The highest risk impact is severe winds, so gusts up to 60 mph from those downburst winds,” Wang said.
“Stronger storms will be capable of strong outflow winds, heavy downpours and small hail,” the National Weather Service said in an alert post on X. “Secure loose items ahead of storms. Use extra caution during travel and outdoor activities.”
“High winds can cause considerable damage,” the Idaho Office of Emergency Management said. “Unsecured objects, such as lawn furniture or trash cans, can become dangerous projectiles.”
High-speed gusts can also overturn vehicles, so you should use caution on the road, according to the Idaho Office of Emergency Management.
“If you are driving, stop at a sturdy building to take shelter,” the state agency said on its website. “Avoid parking or seeking shelter under a freeway overpass or trees. If possible, stay off the roads and avoid unnecessary travel.”
Power outages?
“Another impact is tree branches coming down,” Sophia Adams, a meteorologist with the National Weather Service’s Boise office, told the Statesman previously. “That can also impact power outages, as well.”
You should “trim tree branches away from your house and power lines” to avoid damage from falling limbs, the Idaho Office of Emergency Management said. “If you come across downed power lines, report them to your utility company immediately.”
Report power outages to Idaho Power by calling 800-488-6151.
Be prepared with a power outage kit at the ready, according to Idaho Power.
Here’s what to include:
- Battery-operated flashlights, radio and clock
- Matches
- Blankets
- Bottled water
- Non-perishable food
- Non-electric can opener
- First-aid kit and prescriptions
- Battery or solar-powered chargers
- A block of ice for the freezer
- Extra batteries
Households with babies and pets should prepare formula, diapers and food for emergency conditions as well, according to Idaho Power.
This story was originally published May 27, 2026 at 1:19 PM.
