Forest Fire Warning Signs: How to Detect Danger On Time

Forest fires, also known as wildfire or bushfire, rank among the main ecological disturbances on Earth. 

But what causes forest fires? This uncontrolled combustion of vegetation can be sparked by human carelessness, lightning, extreme heat, lava flow, and other triggers.

Such blazes are not only potentially deadly but can also have a severe negative effect on the environment when outside of their natural cycle. They can spread rapidly, reaching up to 12.5 mph. That’s why it is vital to be able to recognize forest fire warning signs in advance.

Weather That Leads to High Fire Danger

The first signs of wildfire begin to show before the natural disaster begins. ­The weather conditions play a significant role in the birth, growth, and death of a bushfire. 


Extreme heat creates favorable conditions for vegetation fires. During any hot season, trees, sticks, and underbrush absorb heat from the sun, which makes them dry - a perfect potential fuel.

High temperatures make such fuels ignite and burn, which is why it is common that a forest fire starts in the afternoon when the heat is at its peak.

Low Humidity

When the humidity level is low, this means the amount of water vapor in the air is low. That’s when forest fires are more likely to start, making drought conditions a warning signal of a potential fire. 

On the contrary, if the level of precipitation and, consequently, humidity is rather high, the chances of wildfires breaking out are lower.

Strong Wind

The wind’s influence on forest fire behavior is massive. Unfortunately, it is the factor that is also the most difficult to predict. 

Winds supply the flames with extra oxygen, dry its fuel, and boost the speed with which the wildfire spreads. 

Useful Detection Tools

Wildfire smoke and a fire engine

Knowing which weather conditions typically precede wildfires is extremely important, especially in areas susceptible to such disasters. However, there are other ways to predict bushfires.

National Fire News

The National Interagency Fire Center posts plenty of useful information, such as:

  • Reports
  • Weather predictions
  • Daily statistics
  • Updates on current fire levels

The source also has useful tips on wildfire prevention.

Forest Fire Smoke Map

You can check a Fire and Smoke map to identify whether there is any real-time hazard in the zone where you live or in the areas surrounding it.

Wind-Enhanced Fire Potential Index

The WFPI is a globally used meteorological index implemented to estimate the risk of wildfire

It takes into account factors such as fuel moisture and wind. 

The higher the WFPI, the more favorable conditions there are for a bushfire to start. Thus, checking maps based on this index is extremely helpful in predicting where the disaster might strike.

Visible Signs of a Forest Fire

Apart from the notifications available in the media and online, there are also visible signs of approaching bushfire, namely:

Wildfire Smoke

Fire hazard sign and wildland fire smoke

Wildfire smoke is a mix of gases and fine particles from burning vegetation and is toxic for humans and animals. Breathing it in can cause immediate adverse health effects that include:

  • Coughing and scratchy throat
  • Irritated sinuses and runny nose
  • Wheezing and shortness of breath
  • Chest pain and trouble breathing
  • Headaches and stinging eyes

Bushfire smoke is easy to notice from afar. What can be confusing is the distance from the blaze, so don’t underestimate the speed with which the fire spreads.

Distinct Fire On Slopes

Forest fire on a slope next to a residential area

In locations with hilly or mountainous terrain, people can see the flames on the slopes if the bushfire approaches inhabited areas.

It is important to understand that fire usually runs uphill much faster than it crawls downhill. This is due to the fact that it struggles to preheat the fuel when going downward as intensively as when it climbs up.

Fire Danger Sign

Smokey the Bear sign showing high fire danger

A national symbol for the prevention of wildfires in the United States, Smokey the Bear, is a sign that can show you the likelihood of a blaze.

If you see the fire danger scale indicating that the risk is high, very high, or extreme, take caution and check for updates from the state authorities. 

Also, familiarize yourself with the five recommendations on how to prevent bushfires and understand wildfire causes and behavior.

Emergency Alerts

Some services, like Ready for Wildfire, send message alerts to registered users when a bushfire occurs. Be certain to sign up for your local emergency alert system usually offered by your local county.

Stay Alert When Noticing Wildfire Warning Signs

So how to escape forest fire? Careful observation of forest fire warning signs and a timely reaction to them are critical to wildfire safety.

Stay informed on natural hazards and follow the critical steps in the Disaster Deck so you are ready to know exactly how to stay safe and avoid panic.