The Forsyth Fire was a wildfire that burned north of St. George, Utah. The fire was ignited on June 9, 2025, from a lightning strike starting a fire inside a tree trunk. Strong winds on June 19 resulted in the fire to rapidly spread towards Pine Valley. The fire has destroyed 14 residential structures and four outbuildings. The fire reached 100% containment on August 7 at a size of .
Background The Forsyth Fire spread outside of tree as a smoldering flame from strong winds caused the fire to pick up. There were very hot temperatures and strong winds that aided the fire's rapid spread. Additionally, there were single-digit humidity levels, all these contributing to red flag warnings and fire weather watches. Steep terrain drove the fire, along with making it difficult for fire crews to access the area.
Cause
Initially, the Forsyth Fire was believed to have started on June 19, 2025 from a lightning strike. However, after further investigation, it was determined a lightning strike on June 9 struck the base of a tree and smoldered for several days. The fire picked up on June 19 when strong winds during a red flag warning caused the fire to pick up.
Progression June The Forsyth Fire was caused from a lightning strike hitting a tree on June 9, leaving a fire a smolder inside the tree's trunk. On June 19, strong winds during a red flag warning caused the fire to pick up, and smoke was now visible with fire crews responding. That evening, the fire spread to an estimated in dry brush, and grew to early the next day. Evacuation orders had been issued in Pine Valley. Strong winds played a large role in the fire's spread, already at that evening. The Forsyth Fire was experiencing "extreme" fire behavior with 150 firefighters combating it. Several homes had been destroyed.
On June 24, fire's size had reached and still 0% contained, with almost 300 personnel fighting the fire. They prioritized on establishing containment and protecting structures near Pine Valley Reservoir, and completing a burnout operation near Pine Valley Recreation Area. Evacuation orders remained in place for Pine Valley and Grass Valley, with an evacuation warning for Pinto. At a community meeting, a United States Forest Service fire behavior analyst stated there were "some of the highest fire danger levels recorded in the past 25 years".
More firing operations occurred on June 25 to remove vegetation around structures. Firefighters were laying a hose line around Pine Valley, and other crews focused on evacuating residents in Pine Valley and Grass Valley. The fire had grown by . However, "Go Now" evacuation orders were lowered to "Set" levels. The Forsyth Fire, now at , was 8% contained. Despite this, hot and dry conditions were expected, including wind gusts from . Cooler, wetter conditions were forecasted.
Containment lines were established south and west of Pine Valley on June 28, and the fire was 22% contained. The eastern part of the fire was still burning, and steep slopes remained a concern. Suppression efforts were aided by air support crews. The Forsyth Fire was over , but was 26% contained. Hot spots on the north part of the fire were quickly extinguished, and temperatures were upwards of 80 °F.
July onwards A red flag warning was in effect on July 1, with winds up to and a weather system with potential for lightning and outflow winds, with a low chance of rain. A community meeting was scheduled for New Harmony due to an increasing threat from the fire. Fire crews focused on addressing hot spots. However, containment increased to 42% and the fire was . There was still a high chance of dry lightning and gusty winds, as well as a 25% chance of rain and possible microbursts.
July 4 was considered "a critical fire day" because of a warming trend, low moisture, strong winds up to , and dry vegetation. Despite this, Level 2 "Set" evacuations were lowered to Level 1 "Ready" status. The critical fire weather continued into the next day, but a scouting operation revealed there would be no more spread from the southwest part of the fire. The Forsyth Fire was 47% contained.
Warm temperatures, low fuel moistures, winds from , and low humidity levels contributed to fire conditions. Smoke would be visible in St. George, and crews worked on repairing dozer lines. By July 8, the fire had grown to and was 51% contained. Temperatures reached up to 90 °F with the humidity below 15%. The latter was the main reason for moderate fire activity.
Steep terrain drove the fire another , and it was now seen from Pine Mountain overlooking Southern Utah on July 11. Residents believed the fire would come over the mountain. The Forsyth Fire was 58% contained at , mostly spreading along the southern edge. The following day, hot and dry conditions drove the fire which had now reached 67% containment. The fire's size grew to and reached 72% containment on June 13. Aerial drops were aimed at the southern edge. High temperatures and humidity in the single digits triggered a fire weather watch for July 15.
On June 16, a drone was detected in the area, grounding all aircraft operations. Heavy monsoonal rains on July 18 brought cooler temperatures and high humidity, and moisture will last until July 19. There was chance of thunderstorms, and the storm system brought gusty winds. Only the fire's southern edge remained uncontained.
Moist and monsoonal conditions persisted, and containment increased to 99% on July 23 with no perimeter growth. Level 1 Ready evacuations for Pine Valley, Grass Valley, and Gray's Ranch were lifted.
The Forsyth Fire reached 100% containment on August 7 at a size of .
Effects Damage The Forsyth Fire destroyed eighteen structures total: fourteen residences and four outbuildings in Pine Valley, Utah. About 400 other structures were threatened. On June 21, Rocky Mountain Energy enacted a Public Safety Power Shutoff in Southern and Central Utah. , the fire has caused an estimated $35.7 million (2025 USD) in damage.
One firefighter was injured while combating the fire on July 16. He fell off a hill and was airlifted to St. George Regional Hospital. He is expected to make a "full recovery".
Closures and evacuations Mandatory evacuation orders were issued for Pine Valley, Grass Valley, and Gray's Ranch. Evacuation warnings were issued for Pinto. Between 400 and 500 residents were evacuated.
Pine Valley Recreation Area will be closed for the rest of 2025 due to damage from the Forsyth Fire. Reservations were cancelled and refunded. Several forest roads were closed by the United States Forest Service.
Environmental impacts When evacuation orders were lifted, residents were warned of burnt trees falling, ash pits, dust devils, and rockslides attributed to the fire.
There were smoke health concerns for residents; an inversion set over Pine Valley at night. This trapped smoke in, allowing air quality levels to reach hazardous.
+Average air quality from June 30 - July 6CityJune 30July 1July 2July 3July 4July 5July 6Pine ValleyVery UnhealthyVery UnhealthyUnhealthyModerateModerateModerateModerateSt. GeorgeModerateGoodGoodGoodGoodGoodGoodHurricaneGoodGoodGoodGoodGoodGoodGoodZion National ParkModerateGoodGoodGoodGoodGoodGoodCedar CityModerateModerateGoodGoodGoodModerateGood Postfire assessements of Soil Burn Severity showed a notable reduction in burn severity in the Middle Fork of the Santa Clara River, where passage of the fire front was moderated by night-time drone operations. The adjacent North and South Forks of the Santa Clara burned during the daytime, and experienced higher burn severity. October rains caused debris flows over portions of the severely burned areas.
Growth and containment table +Fire containment status Gray: contained; Red: active; %: percent contained;DateArea burnedPersonnelContainmentJune 21 June 22 400June 23 280June 24 509June 25 696June 26 734June 28 687June 29 672June 30 655July 1 660July 2 671July 3 671July 4 664July 5 685July 6 643July 7 574July 8 616July 9 514July 10 548July 11 589July 12 589July 13 580July 14 563July 15 561July 16 509July 17 447July 18 311July 19 275July 20 265July 21 221July 22 232July 23 232 –August 7
See also 2020 Utah wildfires 2024 Utah wildfires 2025 United States wildfires Dragon Bravo Fire White Sage Fire Air quality in Utah
Notes
References
External links Incident Map and Information | Watch Duty Forsyth Fire Incident Information | InciWeb Forsyth Fire Burned Area Emergency Response (BAER) | InciWeb