Northern Rockies Complex Incident Management Team 3
Unaweep Wildfire Module 1 set up a time lapse camera on a prominent lookout west of Sugarloaf Mountain near where they were working on the southeast side of the fire. The view is looking north over the Horse Creek drainage capturing the #DerbyFire as it spread east from the morning of August 21 through the morning of August 24, 2025. Images were captured every 5 minutes. WFM1 Unaweep is based in Grand Junction, CO. #FireYear2025
Video: Clouds move past a dirt road as firefighters and engines periodically move past. Smoke rises from the right-hand side of the video, growing more intense as the Derby Fire spreads east. In the evening hours, the smoke glows yellow and red.
Northern Rockies Complex Incident Management Team 3, Incident Commander Mike Behrens
Location: 13 miles north of Dotsero, CO Start Date: 8/16/2025; Cause: Lightning Size: Est. 5,736 acres Completion/Containment: 5% Total personnel 692
Key Message:
Firefighters continue suppression efforts. Smoldering and lone tree torching persist at higher elevations. Transfer of Command from Northern Rockies Complex Incident Management Team 3 to Rocky Mountain Complex Incident Management Team 3 will occur at 6:00 a.m. on Saturday, August 30, 2025.
Current Status:
Firefighters continue scouting opportunities to construct indirect dozer line on the west side of the fire as well as possibilities to engage direct. On the southern and southeastern flanks, crews are patrolling, mopping up and cold trailing. Cold trailing involves gently feeling the ground and partially burned vegetation for residual heat and extinguishing any remaining hotspots. On the eastern perimeter, firefighters are progressing with indirect handline construction as weather conditions permit. Structure protection crews are working to improve and maintain fire defenses around more than 500 structures along Sweetwater Valley, Sheep Creek, and Red Dirt Creek Road.
WEATHER AND FIRE BEHAVIOR:
Remnants of Hurricane Juliette will bring showers and thunderstorms on Friday, with potential for localized flash flooding and light debris flows. Over the past five days, the fire area received 0.75 inches of rain – more than 100 million gallons of water. Fire activity will be minimal until conditions dry out and several days of low relative humidity make fuels more flammable. However, low moisture levels in dead and downed trees will continue to produce isolated pockets of smoldering in higher elevation conifer stands. Isolated tree torching in subalpine firs is possible. Smoke may increase when sunlight re-energizes these pockets of heat. Gradually warmer and drier weather is expected beginning Sunday.
The Colorado River, Sweetwater, and Red Dirt Creek Roads have all been reopened, and the Garfield County and Eagle County Sheriff’s Offices have changed the evacuation status for Sweetwater Valley, Sheep Creek and Red Dirt Creek areas to pre-evacuation (READY) status: https://arcg.is/S0u4G and www.ecemergency.org.
A Temporary Flight Restriction (TFR) is in place over the Derby Fire. All unauthorized aircraft (including drones) are prohibited from flying near the fire, as they can interfere with authorized air support operations. For more information, visit https://tfr.faa.gov.
All monitors showing GOOD air quality this morning and forecasted to remain GOOD all day. Very little smoke seen on the fire yesterday and the IR flight last night showed very little heat.
Equipo 3 de GestiĂłn de Incidentes Complejos de las Montañas Rocosas del Norte, Comandante de Incidente Mike Behrens UbicaciĂłn: 13 millas al oeste de Dotsero, CO Fecha de inicio: 08/16/2025;   Causa:  Rayos   Tamaño: Est. 5,736 acres FinalizaciĂłn/ContenciĂłn: 5%   Personal total: 692Â
Mensaje clave:
Los bomberos continúan las labores de extinción. Persisten las llamas latentes y la quema de árboles solitarios en las zonas más altas. El traspaso del mando del Equipo 3 de Gestión de Incidentes Complejos de las Montañas Rocosas del Norte al Equipo 3 de Gestión de Incidentes Complejos de las Montañas Rocosas tendrá lugar a las 6:00 a. m. del sábado, el 30 de agosto de 2025.
Estado actual:
Los bomberos continĂşan explorando oportunidades para construir una lĂnea indirecta con excavadoras en el lado oeste del incendio, asĂ como para intervenir directamente. En los flancos sur y sureste, las cuadrillas están patrullando, y continuando con la liquidaciĂłn y rastreo en frĂo. Este sistema consiste en tocando con cuidado el suelo y la vegetaciĂłn parcialmente quemada para detectar calor residual y extinguir cualquier foco de incendio restante. En el perĂmetro este, los bomberos avanzan con la construcciĂłn de una lĂnea manual indirecta segĂşn lo permitan las condiciones climáticas. Las cuadrillas de protecciĂłn de estructuras trabajan para mejorar y mantener las defensas contra incendios en torno a más de 500 estructuras a lo largo de Sweetwater Valley, Sheep Creek y Red Dirt Creek Road.
Northern Rockies Complex Incident Management Team 3
#DerbyFire Ops Update Friday morning, Aug. 29, 2025. Phillip Knaub, Operations Sections Chief, discusses firefighting tactics on the Derby Fire. Northern Rockies Incident Management Team 3 transitions to Rocky Mountain Incident Management Team 3 Saturday August 30th at 6AM. As the drying trend continues through the weekend and into next week, smoke visibility will increase. Crews are working along the southern edge improving containment lines and continuing to extinguish any hot spots. Along the western edge, firefighters are working to create secondary handlines and dozer lines. Along the eastern side, crews are digging handlines to tie into existing lines and continue mopup operations.
Northern Rockies Complex Incident Management Team 3
Derby Fire Weather Update, Friday, August 29, 2025
Samuel Scoleri, Incident Meteorologist trainee, shares the weather forecast for the next few days on the Derby Fire north of Dotsero, CO. Remnants of Hurricane Juliette will bring wetting rain and possible thunderstorms today. Please be cautious as there’s potential for localized flash flooding and light debris flows over roadways. Beginning Sunday, the weather will be gradually warmer and drier.
Location: 11 miles south of Meeker, Colorado Start Date: 08/02/2025 Cause: Lightning Size: Lee Fire: 137,758 acres Containment: Lee Fire: 90% 218 Total Personnel; 9 Engines; 2 Hand Crews; 2 Water Tenders; 2 Dozers
KEY MESSAGE The Lee Fire remains 137,758 acres with 90 percent containment. Fire activity has been minimal, with no growth observed. An infrared (IR) flight detected only a few hot spots, all of which were well inside the fire’s edge. Recent rainfall has kept conditions favorable, though crews remain mindful of flash flooding and debris flows that may follow periods of heavy rain.
CURRENT STATUS Today, firefighters will continue patrols along the fire’s edge to ensure it remains within its footprint. Suppression repair is underway in several areas, including debris removal, with crews working closely with Resource Advisors to complete this work to agency standards and support long-term recovery. Progress remains steady as work continues toward full containment and recovery of the fire area.
WEATHER AND FIRE BEHAVIOR Widespread rain showers are expected on Friday morning and will continue through much of the day. Some heavier showers may produce lightning and thunder. Conditions are forecast to dry out by late afternoon, with clearing skies into the evening. The rainfall will help keep fire activity minimal, though crews will remain alert for lightning strikes and the potential for flash flooding or debris flows in and around the burn area.
CLOSURES AND SPECIAL MESSAGES For accurate up-to-date information on evacuations and road closures for Rio Blanco County go to the Rio Blanco County Sheriff’s Office Facebook page at: https://www.facebook.com/RioBlancoCountySheriffsOffice.
Northern Rockies Complex Incident Management Team 3
Total acreage: 5,735 acres 5% contained 692 personnel
Many kinds of heavy equipment are used on the fire line to clear the area of consumable fuel. By removing trees and brush to mineral soil, they create “fuel breaks” that reduce the fire’s spread.
In this photo, a bulldozer works to scrape vegetation off the surface of the ground. Hand crews may work ahead of dozer operations as “boots on the ground” to cut trees and brush within the dozer’s path.
As of August 26th, there have been approximately 8 miles of bulldozer line put in along the south and west sides of the fire area.
Photo: Taken on the constructed bulldozer line on the Southeast corner of the Derby Fire. S. Rawding/Derby Fire
Northern Rockies Complex Incident Management Team 3
Long term fire analyst, Erin Noonan-Wright, gives an extended outlook regarding fire behavior on the Derby Fire. A fire progression map illustrates the growth of the fire over time. The fire has spread primarily through a mixed conifer/subalpine fir fuel type, slowed in stands of aspen. Long term fire analysts consider trends in winds, rainfall, soil and fuels drought and historical fire behavior to make predictions about how and where the fire could grow.
Heat lingers in heavy fuels in the higher elevation areas of the Derby Fire. The term “heavy fuel” refers to dead trees (also called snags) that are larger than 3 inches in diameter. Large stumps, standing snags and fallen logs are all included in this category.
The larger size of these dead trees makes them slow to ignite, but once smoldering, they’ll hold heat for extended amounts of time. It can take multiple weeks for them to adjust to changes to moisture levels in the atmosphere – earning them the label of “1,000 hour fuels.”
On Wednesday, August 27, 2025, firefighters worked to construct handline on the southeast side of the Derby Fire. When crews encounter burning snags as they construct control lines they use a variety of tools to extinguish the flames. S.Rawding/Derby Fire.
