Boise’s First Scorching 100 Degree Day May Come Earlier Than Normal in 2025

Schools are out for summer and Mother Nature is giving Boise the perfect weather to dive right in.

Enjoy it now, because the National Weather Service says a significant change is on the way starting Sunday. 

READ MORE: If You See This New Color on Weather Maps in Idaho, Stay Inside

National Weather Service Issues Cooler, Wetter Outlook for June 2-6

On Tuesday, the National Weather Service in Boise shared two new maps from its Climate Prediction Center. One gives Boise a 40-50% chance of seeing below normal temperatures next week. The other shows a similar probability of seeing wetter conditions. 

What could that mean for our area? Based on past conditions, normal high temperatures for June 2-6 are 77-78º. Normal daily precipitation for those dates is .03-.04 inches. 

Will Boise Hit 100º Before June?

If you've enjoyed working on your tan since Memorial Day weekend, don’t worry. The unseasonably warm temperatures are sticking around a few more days and they’ll come dangerously close to reaching triple digits! 

The National Weather Service is reminding people in the Boise area to drink lots of water, limit sun exposure and wear a wide-brimmed hat and light clothing this Saturday. May 31 is expected to be the hottest day of 2025 so far with temperatures in the Boise area knocking on the door of triple digits. 

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The way things stand right now, they’re calling for a high of 97º in Boise. That’s just one degree shy of the record high for May 31 set way back in 1910! 

What’s the Earliest Boise Has Reached 100º?

Things could change between now and Saturday, so we wouldn’t completely rule out the possibility of some parts of the area recording triple digits. If they do, would that be the earliest Boise’s reached triple digits? 

We searched through weather records and the answer is “no, but it would be really close.” Weather records show that the earliest that Boise reached 100 degrees was May 29, 1897. 

The earliest we’ve reached triple in the past 15 years? June 3, 2021. The average date for the first triple digit day since meteorologists started tracking this metric in 1875 is July 9.