Weather Forecasts, Road Conditions, and Weather Radar for I-15

Interstate I-15 Weather

I-15 is a major highway running north-south and running 1,433 miles in length. It starts in the north at the Canadian border, connecting with Alberta Highway 4 at the Sweetgrass–Coutts Border Crossing. In the south, it begins in San Diego, California, near the border with Mexico.

The road passes through some of the most spectacular and diverse scenery in the country, including the Mojave Desert, the Wasatch Mountains, and the Rocky Mountains. In general, the road is known for its long stretches of straightaways and lack of traffic congestion.

Heavy snow and high winds can be common while traveling on I-15 through Montana, Idaho, and Utah during the winter.

I-15 Road Conditions in California

Interstate I-15 in California is one of the most important interstate highways in the state. It runs from north to south, connecting Los Angeles and San Diego. The highway is a major corridor for trade and transportation, and it's also popular with tourists who are travelling to visit the many attractions in Southern California.

I-15 Road Conditions in Utah

The section of I-15 through Utah is known as the Veterans Memorial Highway, and is designated as part of the National Highway System. The highway passes through the heart of the Beehive State, traversing some of its most scenic and rugged terrain.

Weather in Idaho on I-15

Idaho is known for its often unpredictable weather. Along Interstate I-15, temperatures can vary greatly depending on where you are. In southern Idaho, temperatures during the summer can reach up to the upper 90s. In the northern part of the state, temperatures can be much cooler. In the winter months, temperatures in the south can dip into the low 20s, while in the north they can dip into the single digits.

The weather in Idaho is also affected by its mountainous terrain. During the winter months, snow is common in the higher elevations. In the lower elevations, rain is more common. Storms, including thunderstorms, can occur year round and can bring strong winds, hail, and heavy rains.

Weather in Montana on I-15

Montana is a state with a wide variety of weather, particularly along the Interstate I-15. This interstate runs from the Canadian border in the north to the Idaho state line in the south. Throughout its route, a traveler can experience a variety of climates.

In the north, along the Canadian border, the weather is generally cold and dry, with cold winters and warm summers. Snowfall can occur during the winter months, and temperatures can drop below freezing.

As one travels further south along the interstate, temperatures become milder and more humid. Rainfall can be experienced in the spring and early summer months, and temperatures can reach up to the mid-90s during the summer months.

As one continues south, the weather becomes more arid and dry. The area around Great Falls experiences hot, dry summers and cold, dry winters. In the winter, temperatures can drop below freezing, and snowfall is common.

Finally, as the interstate reaches the Idaho state line, the climate becomes more mild and humid. Temperatures rarely dip below freezing and rainfall is more frequent.

No matter where you travel along I-15 in Montana, you can be sure to experience a variety of weather conditions.

I-15 Road Conditions

I-15 is a major highway traveling through both Las Vegas, Nevada, and Salt Lake City, Utah. Traffic can often be heavy while traveling through these metropolitan areas.

I-15 Weather Radar

To see Doppler weather radar for I-15, check out our map above!

Major Junctions of I-15

In Montana:

• I-15 South begins at the Sweetgrass-Coutts Border Crossing at the Canadian border near Sweet Grass, Montana.
• I-15 has a major junction at I-315 in Great Falls, Montana.
• I-15 has major junctions at I-90 and I-115 in Butte, Montana.

In Idaho:

• I-15 has a major junction at I-86 in Chubbuck, Idaho.

In Utah:

• I-15 has a major junction at I-84 in Riverdale, Utah.
• I-15 has a major junction at I-215 in North Salt Lake, Utah.
• I-15 has a major junction at I-80 in Salt Lake City, Utah (SLC).
• I-15 has a major junction at I-215 in Murray, Utah.
• I-15 has a major junction at I-70 near Cove Fort, Utah.

In Arizona:

• I-15 has no major junctions in Arizona.

In Nevada:

• I-15 has a major junction at I-215 in Enterprise, Nevada.
• I-15 has a major junction at I-515 in Las Vegas, Nevada.

In California:

• I-15 has a major junction at I-40 in Barstow, California.
• I-15 has a major junction at I-215 in San Bernardino, California.
• I-15 has a major junction at I-10 in Ontario, California.
• I-15 has a major junction at I-215 in Murrieta, California.
• I-15 has major junctions at I-5, I-8, and I-805 in San Diego, California, where I-15 North begins.

This map shows the current & 7-day weather forecast, road conditions, and weather radar for all of US interstate I-15.