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I-15 Interstate Road Conditions
I-15 Road Conditions & Weather
Radar, DOT cameras and live pavement conditions along I-15 from California to Montana — plus closures, road work and the drive broken down into 6 state-by-state stretches.
Updated Sep 15, 2026 2:16 AM UTC · 6 states · Mostly dry, wet in places
Lowest 44°F near Helena, Montana · Highest wind 17 mph near Helena, Montana
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Interstate 15 (I-15) runs from San Diego, California, to Sweet Grass, Montana at the Canadian border, forming a major north–south corridor through the western United States. It passes through cities such as San Diego, Las Vegas, St. George, Provo, Salt Lake City, Pocatello, Idaho Falls, Butte, Helena, and Great Falls.
- Road system: Interstate Highway System
- Year of construction: 1957
- Length: 1,433 miles
Weather data from Sep 15, 2026 2:16 AM UTC
44°F
100°F
17 mph
29.52-30.06 inHg
Current I-15 Conditions by State
California I-15 road conditions
Dry
- Barstow 95°F · 7 mph wind · Dry
- San Diego 71°F · 7 mph wind · Dry
Nevada I-15 road conditions
Dry
- Las Vegas 99°F · 12 mph wind · Dry
- Henderson 99°F · 12 mph wind · Dry
Utah I-15 road conditions
Dry
- Provo 67°F · 4 mph wind · Dry
- Saint George 92°F · 13 mph wind · Dry
- Salt Lake City 68°F · 7 mph wind · Dry
Idaho I-15 road conditions
Dry
- Idaho Falls 62°F · 12 mph wind · Dry
- Pocatello 60°F · 10 mph wind · Dry
Montana I-15 road conditions
Dry
- Great Falls 56°F · 13 mph wind · Dry
- Helena 57°F · 17 mph wind · Dry
I-15 runs 1,433 miles south to north from San Diego, California to Sweet Grass, Montana, crossing 6 states. Its longest stretch is 401 miles across Utah; its shortest is 29 miles in Arizona.
| State | Miles | Share | Cities and mile markers |
|---|---|---|---|
| California | 287 | 20% | San Diego 0 · Barstow 175 |
| Nevada | 124 | 9% | Henderson 33 (11 mi off) · Las Vegas 44 |
| Arizona | 29 | 2% | Beaver Dam 8 |
| Utah | 401 | 28% | Saint George 7 · Provo 265 · Salt Lake City 308 · Ogden 343 |
| Idaho | 196 | 14% | Pocatello 69 · Idaho Falls 118 |
| Montana | 396 | 28% | Helena 192 · Great Falls 279 |
It climbs Cajon Pass at 3,777 ft, where the weather at the summit is not the weather on the approach.
Mile markers count from each state's southern line and start again at the next one, which is how most states number their exits as well. They are measured along the same road geometry these pages draw, so they land within a mile or two of the posted markers. A toll road that runs its own continuous numbering is the exception — on the New York Thruway the posts continue from New York City — and there the figure is how far into the state the place is rather than the number on the sign. Distances are measured state by state, never across a gap.
2 current reports along the route, including 2 full closures. The 1 most serious are listed below. Always check with the responsible state DOT before setting off.
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Road closed
Bridge construction on I-15-BL Both Directions from Commercial St to Willow Ln. All lanes closed. 9/14/2026 7:00 AM MT…
Bridge construction on I-15-BL Both Directions from Commercial St to Willow Ln. All lanes closed. 9/14/2026 7:00 AM MT to 1/8/2027 7:00 PM MT Mon, Tue, Wed, Thu, Fri, Sat, Sun: Active all day Width Restriction: 12ft Length Restriction: 50ft
Arizona I-15 weather conditions
Summaries fetched Sep 14, 2026 12:00 PM UTC
Beaver Dam, AZ weather
- Current weather conditions in Beaver Dam, AZ indicate a clear sky with a temperature of 85.8°F and a dew point of 57.7°F
- The relative humidity is at 39%, and the atmospheric pressure is 29.68 inHg
- Winds are coming from the southeast at 7 mph
- Visibility is good, reaching 9.9 miles
- There are no active weather alerts at this time, and no precipitation is occurring.
California I-15 weather conditions
Summaries fetched Sep 14, 2026 5:01 AM PDT
Barstow, CA weather
- Currently in Barstow, CA, the weather is clear with a temperature of 65.5°F and a dew point of 39.0°F
- The humidity level is at 38%, providing a comfortable atmosphere
- Winds are coming from the west at 8.4 mph, with a visibility of approximately 9.9 miles
- The atmospheric pressure is measured at 29.8 inHg
- No precipitation is occurring at this time, and there are no active weather alerts in the area.
Idaho I-15 weather conditions
Summaries fetched Sep 14, 2026 12:02 PM UTC
Idaho Falls, ID weather
- Current weather conditions in Idaho Falls, ID indicate a clear sky with a temperature of 44.8°F and a dew point of 32.4°F
- The humidity is at 62%, and the pressure is 30.06 inHg
- Winds are coming from the southwest at 8.4 mph
- There is a frost advisory in effect from 3:00 AM to 9:00 AM on September 15, 2026, which could impact outdoor activities during those hours
- Visibility is good at 9.9 miles
- No significant weather impacts are noted at this time.
Montana I-15 weather conditions
Summaries fetched Sep 14, 2026 6:04 AM MDT
Great Falls, MT weather
- In Great Falls, MT, the current weather is mostly clear with a temperature of 45°F
- The humidity is high at 95%, contributing to a dew point of 44°F
- The wind is coming from the southwest at 7 mph, making it feel slightly cooler with a "feels like" temperature of 43°F
- The atmospheric pressure is measured at 29.83 inHg
- Visibility is good at 10 miles
- There are no active weather alerts at this time.
Nevada I-15 weather conditions
Summaries fetched Sep 14, 2026 5:05 AM PDT
Las Vegas, NV weather
- The current weather in Las Vegas, NV, shows clear conditions with a temperature of 84°F
- The humidity level is at 20%, indicating a relatively dry atmosphere
- Winds are blowing from the southwest at 3 mph
- The pressure is measured at 29.65 inHg, and visibility is good at 9.9 miles
- There are no active weather alerts at this time.
Utah I-15 weather conditions
Summaries fetched Sep 14, 2026 6:07 AM MDT
Saint George, UT weather
- Current weather conditions in Saint George, UT indicate a temperature of 79°F with a dew point of 57°F and a relative humidity of 47%
- The wind is blowing from the southeast at 9 mph
- Atmospheric pressure is measured at 29.68 inHg
- The visibility is good at 10 miles, and the weather is mostly clear
- There are no active weather alerts at this time.
Salt Lake City, UT weather
- The current weather in Salt Lake City, UT is clear with a temperature of 54.9°F and a dew point of 37.0°F
- The humidity level is at 51%, indicating a moderately dry atmosphere
- The wind is blowing from the west-northwest at 2.9 MPH
- The visibility is good at 9.9 miles
- There are no active weather alerts at this time.
I-15 Traffic Cameras
updating…(C 043) I-15 : Just South Of Poway Road, San Diego
Photo from — last answered 2 hours ago, so this is the last frame we have
(C 086 )I-15 : West Bernardo Drive / Pomerdo, San Diego
Photo from — last answered 2 hours ago, so this is the last frame we have
(C087) I-15 : Via Rancho Parkway, Escondido
Photo from — last answered 2 hours ago, so this is the last frame we have
(C091) SB 15 : Del Lago, Escondido
Photo from — last answered 2 hours ago, so this is the last frame we have
(C382) SB 15 : El Norte Pkwy_B, Escondido
Photo from — last answered 2 hours ago, so this is the last frame we have
(C383) SB 15 : El Norte Pkwy_T, Escondido
Photo from — last answered 2 hours ago, so this is the last frame we have
I-15 Road Weather FAQ
- Is I-15 closed right now?
- Yes — 2 full closures are reported on I-15 as of Sep 15, 2026 2:46 AM UTC.
- What are I-15 road conditions today?
- The map on this page colors the route along I-15 by what is on the pavement right now — dry, wet, slush, snow or ice — from radar and surface data, last updated Sep 15, 2026 2:16 AM UTC. Right now temperatures run from 44°F to 100°F and the strongest wind is 17 mph.
- How long is Interstate 15, and which states does it cross?
- I-15 runs 1,433 miles south to north, from San Diego, California to Sweet Grass, Montana, through 6 states: California, Nevada, Arizona, Utah, Idaho and Montana. The longest stretch is 401 miles across Utah. Mile markers restart at each state line, so Barstow is around mile 175 in California.
- Are there mountain passes on I-15?
- Yes — one on this site, Cajon Pass at 3,777 ft. Each has its own summit page.
- Are there live traffic cameras on I-15?
- Yes. This page shows 6 live views on I-15 from the state transportation departments' own camera feeds, further down the page, refreshed each time you load it.
- How often are I-15 road conditions updated?
- The road surface and weather layers are rebuilt whenever this page is opened with data more than ten minutes old, and refreshed on a schedule in between, so nothing here is more than about two hours old even on a road nobody has looked at. Closures and road blocks are re-imported from the state 511 feeds every fifteen minutes, and the written state-by-state summaries are refreshed daily. Every section on this page carries the time its data was fetched.
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