Heat advisory in effect ahead of storms and cooler weekend

It will be smokin' hot today with highs from 90-100 for most of our viewing area. Light winds and sunny skies keep us dry for today and heat building into the advisory hours of 12noon to 10pm.

Smokin’ hot today, then a windy thunderstorm cooldown tonight.

If you have outdoor plans across East Idaho or western Wyoming, get them done early. We’re heading into one of the hottest days of the summer, with abundant sunshine, very little wind and afternoon temperatures climbing into the 90s to around 100 degrees for much of the region.

☀️ TODAY: HOT, DRY & SUNNY

The morning starts relatively comfortable, but temperatures climb quickly after sunrise. By lunchtime, the heat becomes the big story, with the hottest part of the day running through the afternoon and early evening.

Across the Snake River Plain, communities along I-15—including Idaho Falls, Rexburg, Shelley, Blackfoot and Pocatello—can expect highs generally in the mid-90s to around 100 degrees, with some locations potentially exceeding 100.

The desert areas will be especially hot, while higher elevations around Island Park, Driggs, Tetonia and the surrounding mountain valleys stay cooler but still run unusually warm.

For anyone heading to the river, reservoir, ball field, golf course, trail or backyard barbecue, remember that sunshine and dry air can make it easy to underestimate how quickly you can become dehydrated.

⚠️ HEAT ADVISORY: NOON–10 PM

The National Weather Service has issued a Heat Advisory for several East Idaho desert and mountain communities, including areas from Mud Lake toward Driggs and Tetonia.

The most important thing today isn't changing your plans—it’s changing how you approach them.

If you're working or playing outside:

• Drink water regularly before you feel thirsty.
• Take frequent breaks in shade or air conditioning.
• Avoid prolonged, strenuous activity during the hottest afternoon hours.
• Wear lightweight, loose-fitting clothing and a hat.
• Never leave children, pets or anyone vulnerable in a parked vehicle.
• Check on elderly neighbors, family members and anyone who lives or works without reliable air conditioning.
• If you're hiking, boating or recreating, bring more water than you think you'll need.

Watch for warning signs of heat illness, including headache, dizziness, nausea, unusual weakness, heavy sweating or confusion. Move into a cooler environment and get help if symptoms become severe.

⛰️ WESTERN WYOMING

Western Wyoming gets some relief from the elevation, but don't let that fool you into thinking the heat isn't a concern.

Jackson, Star Valley and surrounding mountain communities will be warmer than normal, with plenty of sunshine through much of the day. Trails, lakes and mountain recreation will be inviting, but the combination of strong summer sun and warm temperatures can still lead to dehydration—especially during long hikes or strenuous activity.

If you're heading into the mountains, take plenty of water and don't count on a cooler afternoon to eliminate the heat risk.

⛈️ TONIGHT: THE WEATHER FLIPS

The heat doesn't simply fade away tonight—the atmosphere becomes much more active.

Increasing moisture will push into the region, with clouds building through the day and thunderstorms developing later tonight.

Some storms could become gusty, with wind gusts approaching 50 mph. That means a quiet, hot afternoon could turn into a very different evening in a hurry.

If you're camping, boating, attending an outdoor event or leaving patio furniture, tents or other lightweight items outside, secure things before the storms arrive.

And if you're caught outside when thunderstorms develop, get inside a substantial building or hard-topped vehicle. Don't wait for the storm to arrive overhead before deciding where you're going to take shelter.

🌡️ SATURDAY: MUCH-NEEDED RELIEF

Those storms bring a dramatic change for Saturday.

Temperatures fall back into the 80s, making it much more comfortable for outdoor activities. That puts us much closer to normal for late August, when seasonal afternoon highs are generally in the upper 80s.

So if today feels like the peak of summer, that's because it is—but the heat wave gets broken tonight.

Bottom line: Take advantage of the cooler morning hours today, respect the heat from noon through 10 PM, keep water handy, check on people and pets, and be ready for thunderstorms and strong wind tonight. By Saturday, East Idaho and western Wyoming get a much more comfortable taste of late-summer weather.

The National Weather Service has included many of our desert and mountain communities from Mud Lake to Driggs and Tetonia in the heat advisory today due to the danger for many of heat. Snake River Plain cities along I-15 will see max temps again today from 95-100+ degrees. Please stay cool and take care of others. Hydrate and take breaks.

Storms with more moisture flowing starting with clouds today and then we hit some windy thunderstorms tonight with gusts to 50mph late. These storms will cool us down into tomorrow with highs in the 80's. Seasonal averages would normally be in the upper 80's.