With wildfire season well underway, what is a Red Flag Warning

It is only mid-July, and already Eastern Washington has had more than two dozen wildfires. There has also been a pair of wildfires in the Northern Cascades, and the Mount Tom Creek fire in the Olympics. The wildfire season is well underway.

Conditions are dry statewide, particularly east of the Cascades. According to the U.S. Drought Monitor, Eastern Washington is in moderate or severe drought, while much of Western Washington is abnormally dry.

If longer range weather forecast charts are on track, there is no significant or wetting rain (0.25 inch of rain) in sight through near the end of this month.

In Western Washington, the last significant rainfall came on June 9, more than a month ago. Seattle-Tacoma International Airport (SEA) had just over a half-inch that day, while Olympia and Everett – Paine Field both received over an inch of rain.

Historically, mid-July to mid-August is the driest time of the year. So conditions are on track to become even drier. Light fuels like unirrigated grasses and shrubs are ready to burn now. Larger fuels like trees are not far behind.

What is a Red Flag Warning

What is a Red Flag Warning? Many parts of Eastern Washington have already had several days in the past month when a Red Flag Warning was in effect.

A Red Flag Warning is issued by the National Weather Service (NWS) when weather and environmental conditions are ripe for a rapidly spreading wildfire for a targeted geographic area within the next 24 hours or is imminent. The environmental conditions include very dry conditions. The weather side of the formula includes very low relative humidity, windy conditions, and the potential for lightning. Any fire that starts will experience rapid fire growth.

There is also a more Extreme Red Flag Warning when all these conditions are met at a more severe level, particularly very strong winds that can fan the flames and move the fire quickly, leaving little time to get out of harm’s way. The Emergency Alert System (EAS) and Wireless Emergency Alerts (WEA) reaching smartphones in the warning area are activated by local authorities.

The NWS issues a Fire Weather Watch with a greater lead time of more than 24 hours when those hazardous weather conditions are anticipated. This lead time allows firefighting agencies and the public to prepare in advance if a wildfire breaks out in the next day or so.

Weather this week

The weather pattern for Western Washington this week features moderating air from the Pacific Ocean, keeping temperatures more seasonable. High temperatures are forecast to warm into the 70s and up to the mid-80s in the usually warmest locations, such as the Cascade foothills and areas south of Puget Sound.

A very weak weather system is anticipated to cross the region Thursday, offering a limited chance of light rain. Otherwise, the week is expected to offer areas of morning clouds, otherwise plenty of sunshine.

By this coming weekend and into early next week, higher pressure over the Rocky Mountain region is forecast to shift west toward the coastline, bringing warmer temperatures that could crack the 90-degree mark once again. In addition, the weather system’s southerly flow aloft may bring monsoonal moisture northward from the desert Southwest.

This higher-level moisture could induce thunderstorm activity mainly from the Cascades eastward. At a time when conditions are quite dry, lightning can initiate more wildfires.

Actions to take

Around homes and businesses, now is the time to build defensible space. A number of actions to take can be found at the National Fire Protection Association’s website, such as clearing debris from gutters and roofs.

Avoiding fire starts is also critical. For much of the interior of Western Washington, outdoor burn bans are already in place into September. For local details about outdoor burning, visit your neighborhood fire district website.

While driving, keep burning materials inside the vehicle and tighten tow chains to avoid sparking off the pavement. When camping, ensure campfires are cold before leaving the site. History shows that humans start four out of five wildfires. The recent wildfires near Chelan and Vantage were both initiated by people.

Eastern Washington already has very dry conditions in place. Western Washington is not far behind. For the west side, a Fire Weather Watch and a Red Flag Warning may be in effect as this summer moves into August.

Ted Buehner is the KIRO Newsradio meteorologist. Follow him on X and Bluesky. Read more of his stories here.