Dangerous Fire Weather Builds Across the West as Dry Lightning, Powerful Winds and Drought Threaten to Spread Wildfires

Cold front brings an unusual fire threat

A dangerous fire weather setup is developing across drought-stricken parts of the western United States, and the trigger may seem counterintuitive: a cold front.

Forecasters expect a large cold front to develop in the Pacific Northwest on Thursday, then push southeast into the Intermountain West. Along its leading edge, dry lightning could ignite new fires. Behind and around the system, strong winds may spread those fires quickly and worsen blazes already burning.

Across parts of the West, dry vegetation, drought stress and strong wind are combining into a pattern that forecasters describe as very high to extreme fire danger.

Dry lightning first, then several days of wind

The first hazard is lightning. The second is wind.

Basil Newmerzhycky, a forecaster for the Great Basin Coordination Center in Salt Lake City, UT, said the risk begins with lightning over southern and eastern areas, then shifts into a prolonged wind event.

Basil Newmerzhycky: “We have high risk for lightning moving across southern and eastern areas today and tomorrow, followed by several days of strong winds."

The Salt Lake City-based center organizes firefighting resources for the Intermountain West, a region that includes parts of Arizona, ID, Nevada, UT and Wyoming.

Newmerzhycky warned that the danger will rise into the weekend.

Basil Newmerzhycky: “Friday into the weekend, overall fire danger is very high to extreme. Several of our fires are already showing extreme fire behavior."

Windstorm expected across five states

Forecasters expect a strong windstorm beginning Friday across Utah, CO, Arizona, NV and New Mexico.

Daniel Swain, a climate scientist at UCLA and the National Center for Atmospheric Research, said the broader West will be highly flammable during the event because vegetation moisture is very low and winds will be widespread.

Daniel Swain: “A lot of the West is going to be very flammable during this period, with very low vegetation moisture, very dry fuel, essentially, and a lot of wind."

Daniel Swain: “I am concerned."

Swain said the windstorm could persist through Sunday in many places, making the event both widespread and long in duration.

Daniel Swain: “It’s widespread, it’s going to be long in duration, and it’s going to be occurring at an unusual time of year for there to be long-duration widespread wind events, which is summer, during fire season and during a significant drought."

Rain near the coast, fire danger inland

The front will not affect every area in the same way. Along parts of the Oregon and Washington coast, and west of the Cascade Mountains, the system is expected to produce significant rainfall.

Farther inland, the same front becomes a fire weather threat.

In Utah, widespread gusts of 40 to 50 mph are expected. Glen Merrill, a National Weather Service meteorologist and hydrologist based in Salt Lake City, UT, said vegetation across the region is dry and primed to burn.

Glen Merrill: “That creates hazardous fire weather conditions where fires can grow really quickly."

Wind over dry fuels can turn a small ignition into a fast-moving fire. Dust can rise from open ground. Smoke can move quickly across roads and valleys. Fire lines can become harder to hold when gusts arrive in repeated waves.

Utah fires already showing rapid growth

Utah is already dealing with two large wildfires that could worsen as winds intensify.

The Iron Fire, which started Friday, has burned more than 37,000 acres. It nearly destroyed the town of Eureka, UT, which remains evacuated.

Glen Merrill: “The fire came right up to the edge of the town."

The Cottonwood Fire, near Beaver, UT, started Monday and has already burned about 60,000 acres. It has doubled in size each day.

Glen Merrill: “You can see, just from the rate of growth, just how quickly these fires have grown and spread. That’s due to the dry vegetation and fuels the fire consumes and the weather conditions."

The fire growth shows how quickly the landscape can respond when drought, dry fuels and wind align. In this pattern, fire behavior can accelerate within hours.

Drought and low snowpack deepen the risk

Utah remains in drought after recording its lowest-ever snowpack this year. A spring heat wave pushed temperatures to about 30 degrees above average in March, starting runoff earlier than usual.

Merrill said water storage has already been affected.

Glen Merrill: “Right now, we should be topping our reservoirs off, but we’ve already been drawing from our reservoirs for over a month in many areas."

The Cottonwood Fire is burning above 10,000 feet, an elevation where melting snow and moist soil would ordinarily help prevent fires so early in the year.

Glen Merrill: “Places that are burning now have typically just come out of their snowmelt."

Glen Merrill: “In 2023, areas burning now still had snow on the ground."

That contrast is stark. Areas that would normally still be damp are now dry enough to burn, and they are burning before the heart of fire season has arrived.

Nearly 2.8 million acres already burned this year

All signs point to a long and severe fire season across western states.

According to the National Interagency Fire Center, nearly 2.8 million acres have already burned this year. That is about 800,000 acres above the 10-year average for this date.

The center produces forecast maps showing fire potential through September. Those outlooks show large areas with above-average fire potential and no areas below average.

The map points in one direction: continued risk.

Why this setup is so dangerous

The fire weather risk comes from several hazards arriving close together.

• A cold front is expected to generate dry lightning across parts of the Intermountain West.
• Strong winds are forecast from Friday into the weekend across Utah, CO, Arizona, NV and New Mexico.
• Vegetation moisture is very low after drought and poor snowpack.
• Existing fires in Utah are already showing rapid growth and extreme behavior.
• Fire potential remains above average across large areas through September.

Dry lightning can start fires. Strong wind can spread them. Drought makes the landscape easier to ignite.

In the West this week, those ingredients are arriving together.