With several large wildfires burning across Colorado in recent weeks—particularly the Aspen Acres Fire—many people have been watching weather forecasts more closely than usual. While firefighters, aircraft, and heavy equipment are often the most visible parts of a wildfire response, there’s another critical group working behind the scenes: meteorologists.
Weather plays a major role in how a wildfire behaves. In fact, changes in wind, humidity, temperature, and even nearby thunderstorms can determine whether a fire remains manageable or suddenly grows out of control. That’s why meteorologists are an essential part of wildfire operations.
Weather Drives Fire Behavior
Wildfires need three basic ingredients: fuel, oxygen, and heat. While firefighters can’t control the weather, they can use weather forecasts to better predict how a fire will spread.
Meteorologists closely monitor factors such as:
- Wind speed and direction: Strong winds can rapidly spread flames and carry embers miles ahead of the main fire, creating new spot fires.
- Relative humidity: Dry air allows vegetation to ignite more easily and burn more intensely.
- Temperature: Hotter temperatures help dry out grasses, shrubs, and forests, making them more flammable.
- Thunderstorms: While rain can help firefighters, storms often produce gusty, erratic winds and lightning that can both intensify existing fires and ignite new ones.
Even relatively small weather changes can dramatically alter fire behavior within minutes.
More Than the Forecast You See on TV
The weather forecast you watch each evening is designed for an entire city or region. Firefighters need something much more precise.
The National Weather Service produces Fire Weather Forecasts twice each day during fire season. These forecasts focus specifically on weather conditions that influence wildfire behavior.
When a wildfire is actively burning, meteorologists can also prepare Spot Forecasts—highly detailed forecasts tailored to a specific fire location. These forecasts help incident commanders decide where crews can safely work, where aircraft should operate, and how fire suppression strategies may need to change throughout the day.
Meet the IMET: The Meteorologist on the Fireline
For larger or more complex wildfires, the National Weather Service may deploy an Incident Meteorologist, commonly known as an IMET.
Unlike meteorologists working at a forecast office, an IMET travels directly to the wildfire and becomes part of the incident management team. There are only about 40 IMETs nationwide, making them a highly specialized resource.
These meteorologists are cross-trained not only in forecasting weather but also in wildland fire behavior. They work alongside fire managers and Fire Behavior Analysts (FBANs) to provide real-time weather intelligence throughout the incident.
Hyper-Local Forecasting Saves Lives
An IMET’s forecasts are incredibly detailed.
Instead of predicting weather for an entire county, they may forecast conditions for just a few square miles surrounding the fire. These forecasts often focus on the next several hours—or even the next 30 to 60 minutes.
This level of precision allows firefighters to prepare for sudden weather changes, including:
- Rapid wind shifts caused by passing weather fronts
- Strong thunderstorm outflow winds
- Dry lightning capable of starting new fires
- Dangerous downbursts that can quickly change a fire’s direction
Knowing when and where these changes are expected gives incident commanders valuable time to reposition crews and adjust firefighting tactics before conditions become dangerous.
Technology in the Field
When deployed, IMETs don’t rely solely on nearby weather stations.
They bring specialized equipment known as an Advanced Technology Meteorological Unit (ATMU)—a portable weather forecasting station that includes communications equipment, satellite connectivity, computers, and weather observing instruments.
Using real-time weather observations, Doppler radar, satellite imagery, computer weather models, and local measurements, IMETs continuously update forecasts as conditions evolve.
This allows fire managers to receive the latest weather information without waiting for standard forecast updates.
Colorado’s Challenging Fire Weather
Colorado presents unique forecasting challenges because of its varied terrain.
Mountains, valleys, foothills, and plains all influence local weather. Winds can funnel through canyons, storms can develop rapidly over higher terrain, and humidity levels often vary dramatically over short distances.
During summer, dry thunderstorms are especially concerning. While they may produce little rainfall, they can generate powerful wind gusts and lightning—two ingredients that can quickly worsen wildfire conditions.
These localized weather effects make specialized forecasting even more important during Colorado’s wildfire season.
Behind Every Fire Forecast
When we think about wildfire response, we naturally picture firefighters battling flames on steep hillsides or aircraft dropping water and fire retardant overhead.
But every major wildfire response also depends on meteorologists.
As Colorado continues to face an active wildfire season, the work of meteorologists and IIMETs remains one of the most important—and often overlooked—tools in protecting both firefighters and communities.