What Is A Red Flag Warning? | OSU Extension Service

Skip to main content

Main navigation

  • Topics
    • Animals and livestock
      • Beef cattle
      • Bees and pollinators
      • Commercial fishing, crabbing and clamming
      • Dairy
      • Horses
      • Poultry and rabbits
      • Sheep and goats
      • Swine
    • Business and economics
      • Business management
      • Business marketing
      • Estate and succession planning
      • Finance, budgeting and taxes
      • Rural economic development
    • Community vitality
      • Agritourism
      • Community science
      • Community disaster preparedness
      • Community planning
      • Health outreach
      • Local, regional and community food systems
    • Crop production
      • Berries, table grapes and kiwifruit
      • Field crops
      • Fruit trees
      • Hazelnuts and nut crops
      • Hemp
      • Nursery and greenhouse
      • Organic agriculture
      • Pastures and forages
      • Soil
      • Vegetables and specialty seeds
      • Wine grapes
    • Food
      • Commercial food processing
      • Farm food safety
      • Food security
      • Home food preservation
      • Home food safety and storage
      • Nutrition and healthy eating
      • Recipes
      • Wine, beer, cider and spirits
    • Forests, woodlands and rangelands
      • Christmas trees
      • Cutting and selling trees
      • Fire
      • Forest health and management
      • Non-timber forest products
      • Rangeland conservation and management
      • Tree care
      • Wood processing and products
    • Gardening, lawn and landscape
      • Monthly garden calendars
      • Bees and pollinators
      • Berries and fruit
      • Flowers, shrubs and trees
      • Garden soil and compost
      • Gardening techniques
      • Garden vegetables and herbs
      • Lawn and turfgrass
      • Urban forestry
      • Wildlife
    • Outdoors and environments
      • Climate change
      • Environmental education (PreK-12)
      • Fish and aquatic life
      • Sustainability
      • Wildlife
    • Pests, weeds and diseases
      • Healthy homes
      • Insects
      • Integrated pest management
      • Invasive species
      • Nuisance wildlife
      • Pesticide safety and education
      • Plant diseases
      • Weeds
    • Water and watersheds
      • Fish and aquatic life
      • Irrigation
      • Ponds
      • Residential water and wells
      • Riparian areas
      • Water management and conservation
    • Youth, families and health
      • Family emergency preparedness
      • Food security
      • Healthy aging
      • Healthy homes
      • Nutrition and healthy eating
      • Parenting
      • Physical activity
      • Youth education resources
  • Get involved
    • Programs
    • Projects
    • Events
  • About
    • About us
    • Our leadership
    • Get involved
    • News
    • Career opportunities
    • Donate
  • Contact us
    • Find a location near you
    • Faculty and staff
    • Ask Extension
  1. OSU Extension Catalog
Peer reviewed (Gray level) What is a red flag warning?
  • English
  • Español
Carrie Berger Published February 2020, Reviewed 2024 | Print (or Save as PDF) | Share

The National Weather Service issues red flag warnings to alert land management agencies to critical weather and fuel moisture conditions that could lead to rapid increases in wildfire activity.

What does a red flag warning mean for the public?

A red flag warning means high fire danger with increased probability of a quickly spreading fire in the area within 24 hours. Authorities may issue a burn ban and ask the public to avoid burning. Some other things the public can do to be more mindful on red flag warning days:

  • Secure safety chains on trailers.
  • Don’t drive over dry grass or vegetation.
  • Postpone target shooting.
  • Avoid yard work or welding near dry vegetation.
  • Report any fire, smoke or unsafe activity that could lead to a fire.

The weather criteria for red flag warnings vary. The National Weather Service issues these forecasts from regional offices in Seattle, Spokane, Portland, Pendleton, Medford and Boise for specific zones of similar vegetation and topography (see map). Each forecast office covers many fire weather zones.

Please call 911 if you need to report a fire. 911 Emergency Dispatch will know the proper authority to send to the fire.

What weather criteria are considered?

  • Drought conditions
  • Expected afternoon high temperatures
  • Minimum relative humidity
  • Daily vegetation moisture calculations
  • Sustained winds, wind gusts or erratic winds
  • National Fire Danger Rating System index of “High or Higher”
  • Haines Index of atmospheric stability
  • Dry lightning
  • Frontal passages

How do fire agencies respond to a red flag warning?

Fire agencies respond to the forecasts by positioning additional firefighting resources, increasing detection flights and prevention patrols, or extending staffing hours. The forecasts are critical information for planning prescribed burns.

This article was written in partnership with the Northwest Fire Science Consortium.

Previously titled What is? Red flag warning Man in hard hat with a burning pile of debris in forest setting Want to learn more about this topic? Explore more resources from OSU Extension: Fire Fire weather zones of similar vegetation and topography

Fire weather zones of similar vegetation and topography: Seattle, Spokane, Pendleton, Portland, Medford, Boise.

Credit: Pacific Northwest Geopgraphic Area Coordination Center Published Feb 2020, Reviewed 2024 Author Carrie Berger Fire Program Manager

Was this page helpful?

YesYesYesYesNoNoNoNo Extra feedback Send feedback

Related Content from OSU Extension

Small plant with tubular bright red flowers on short green stems sits in bed of gravel and rock Credit: Amy Jo Detweiler, © Oregon State University (Cropped from original)

Fire-resistant plants for home landscapes

Home landscaping is an important part of a community's resistance to wildfire. Learn what plants can help you create an attractive environment and reduce the risk of fire.

Amy Jo Detweiler, Stephen Fitzgerald, Ariel Cowan, Neil Bell, Thomas Stokely | Oct 2023 | OSU Extension Catalog Peer reviewed (Orange level)

Fire FAQs—Air quality impacts from prescribed fire and wildfire: How do they compare?

Compares the impacts that prescribed fires and wildfires have on air quality. One in a series of fire FAQs that are based on questions Forest & Natural Resource Extension agents and specialists have received from the people they serve.

Carrie Berger, Stephen Fitzgerald, Dan Leavell, Janice Peterson | Jun 2022 | OSU Extension Catalog Peer reviewed (Orange level)

A worker in protective gear feeds tree branches into a large yellow wood chipper during a brush-clearing effort in a forested area. Credit: Kym Pokorny (Cropped from original)

Douglas County residents learn Firewise strategies to prepare for wildfire season

Neighbors team up with OSU Extension to clear brush and reduce wildfire risks.

Kym Pokorny | Jun 2, 2022 | News story

Smoke drifts from a wildfire burning on a forested hillside above a winding road on a clear day. Credit: Dan Morrison (Cropped from original)

Teamwork and planning pay off in wildfire resilience for Linn County

Collaboration key to securing secure $8.7M to protect county's eastern communities over five years.

Chris Branam | Oct 23, 2025 | News story

A colorful map of Oregon is divided into regions with the title 'Not all Flame's the Same,' highlighting different fire-related zones such as Coast Range, Blue Mountains, and East Cascades. Credit: Gretchen Bracher and Christina Friehauf (Cropped from original)

OSU Extension publishes accessible resources on Oregon's fire ecology

Not All Flame’s the Same explains regional fire ecology and Oregon’s diverse fire regimes.

Chris Branam | May 23, 2025 | News story

A blue and white sign reads "Tsunami Evacuation Route" with an arrow pointing to the left. Credit: Tiffany Woods (Cropped from original)

Oregon State and HazAdapt expand emergency preparedness statewide

People engaged with trusted safety guidance across 31 hazards 624 times during the summer.

Chris Branam | Oct 2, 2025 | News story

Two men stand outdoors on a dry, brushy landscape, talking face to face, with one wearing an orange shirt and sunglasses and the other wearing a light blue shirt and cap. Credit: Stephen Ward (Cropped from original)

Grazing research cuts wildfire fuels and feed costs in Malheur County

OSU Extension project targets invasive grasses on public rangelands.

Henry Carnell | Oct 29, 2024 | News story

A winding gravel road leads through a valley of scorched hillsides with patches of green farmland and distant mountains. Credit: Jacob Powell (Cropped from original)

Extension helps land nearly $6 million for wildfire resilience in Wasco County

New funding strengthens local capacity, supports hazard reduction and fuels assessment across 80,000 acres.

Henry Carnell | Jul 2, 2024 | News story

A compact, drought-tolerant clump of pineleaf penstemon displays bright red tubular flowers above fine green foliage in a gravelly rock-garden setting. Credit: Amy Jo Detweiler (Cropped from original)

OSU Extension shows how to design attractive, fire-resistant home landscapes

Publication helps homeowners create fire-wise landscapes without sacrificing curb appeal.

Francesca Lear | Jun 20, 2024 | News story

A person holding a paper gestures while speaking to a small group seated among logs and shrubs in a forested area. Credit: Kris Norris (Cropped from original)

Wildfire and water inspire new art exhibit influenced by Extension science

PLAYA residency brings artists and OSU fire specialists together for collaborative storytelling.

Francesca Lear | Apr 18, 2024 | News story

Our Future in Our Hands Credit: Christina Friehauf (Cropped from original)

OSU Extension earns national honors for wildfire and forestry education publications

Award-winning resources help Oregon families reduce wildfire risk and support resilient forests.

Francesca Lear | Apr 5, 2024 | News story

A black and white cow wearing a GPS tracking collar stands in a grassy field with another cow in the background. Credit: Amanda Loman (Cropped from original)

Virtual fencing shows promise for reducing wildfire risk on rangelands

OSU and USDA-ARS study finds GPS collars on cattle can help create fuel breaks in sagebrush landscapes.

Sean Nealon | Sep 27, 2022 | News story

A burned and heavily damaged fire truck sits abandoned by the roadside. Credit: David Baker (Cropped from original)

OSU report reveals ongoing struggles for Santiam Canyon wildfire survivors

OSU researchers heard firsthand how the 2020 wildfires continue to affect survivors’ physical and mental health.

Molly Rosbach | Feb 1, 2022 | News story

A firefighter in yellow protective gear uses a drip torch to ignite a controlled burn on a pile of forest debris. Credit: Kym Pokorny (Cropped from original)

Prescribed fire training builds foundation for effective landscape restoration

NRCS staff learn how prescribed fire restores Oregon landscapes.

Kym Pokorny | Jan 14, 2022 | News story

A firefighter trainee walks through an open pine stand while conducting a low-intensity prescribed burn, with small flames creeping along the forest floor and light smoke drifting between the trees. Credit: Carrie Berger (Cropped from original)

OSU Extension Fire Program expands wildfire education and partnerships

Webinars, training and regional specialists strengthen Oregon’s fire preparedness.

Francesca Lear | Jun 4, 2024 | News story

Smoke fills the sky above Alicia Christiansen's home in Glide, Oregon, on Sept. 8. Photo: Alicia Christiansen (Cropped from original)

Extension employees share firsthand accounts of wildfire evacuations

Reflections on evacuation, resilience and protecting what matters most.

Chris Branam | Sep 16, 2020 | News story

ChatGPT said:  Three ripening tomatoes, shaded from green to orange-red, rest on the soil beneath leafy vines in a garden bed. Credit: Chris Branam (Cropped from original)

Is wildfire ash on garden produce safe to eat?

OSU Extension shares guidance for cleaning fruits and vegetables after wildfires.

Kym Pokorny | Sep 4, 2025 | News story

Courtesy: Oregon RFPA (Cropped from original)

Rangeland Fire Protection Associations reduce wildfire tensions in Oregon and Idaho

Known as Rangeland Fire Protection Associations, these groups originated in the 1960s in Eastern Oregon and have rapidly expanded over the last 20 years.

Chris Branam | Oct 24, 2019 | News story

Ask Extension

Have a question? Ask Extension!

Ask Extension is a way for you to get answers from the Oregon State University Extension Service. We have experts in family and health, community development, food and agriculture, coastal issues, forestry, programs for young people, and gardening.

Ask us a question

Tag » What Is Red Flag Warning