Firefighters on the Bighorn Fire near Tucson prepare for Red Flag conditions Sunday and Monday

The fire has grown to over 95,000 acres, approaching “megafire” status of 100,000 acres

(Originally published at 2:29 p.m. MDT June 27, 2020)

Summerhaven Bighorn Fire Tucson Mt Lemmon
Night operations at Summerhaven on the Bighorn Fire. Photo by David Melendez June 26, 2020.

The National Weather Service in Tucson has issued a Red Flag Warning for Tucson and the Bighorn Fire area from noon to 8 p.m. MST Sunday and from noon to 8 p.m. MST Monday. The prediction is for strong winds, low humidity, and very high fire danger. The wind is expected to be out of the southwest at 15 to 25 mph with gusts to 35 mph Sunday, and on Monday, southwest at 15 to 20 mph with gusts between 35 and 40 mph. The relative humidity will be 10 to 17 percent in the valleys and 13 to 21 percent in the mountains.

From the Incident Management Team on Saturday:

“Friday night, burnout operations south of Davis Spring Road and 4 miles west of Redington were conducted to reduce the risk of eastward fire spread. Aerial ignition operations were conducted near Palisade Canyon and Green Mountain to improve firelines and reduce the risk of uncontrolled fire reaching the Catalina Highway. East of Saddlebrook a firing operation improved firelines. Holding, mop up and structure protection was the focus in Summerhaven, Willow Canyon, and Saddlebrook. Biosphere, Oracle, and Sabino Canyon were in patrol status.

“Saturday’s Activities: Crews will hold and improve line near Willow Canyon, Palisade Canyon, Green Mountain, and south of the Davis Spring Road. Hotshot crews will build fireline on the south side of Green Mountain. A hand crew will work to extinguish a hotspot approximately three miles northeast of Catalina State Park.  East of the fire, construction will continue on contingency lines by connecting to existing road systems. Structure protection will be in place for Saddlebrook and along the Catalina Highway.Initial attack resources are pre-positioned around the fire.”

A mapping flight Friday night determined that the Bighorn Fire had burned 95,225 acres, a 24-hour increase of over 7,000 acres.

(To see all articles about the Bighorn fire, including the most recent, click here.)

map Bighorn Fire Tucson Mt Lemmon
3-D map of the Bighorn Fire looking southeast. The red line was the perimeter at 10:31 p.m. MDT June 26, 2020. The green line was the perimeter about 48 hours before.
map Bighorn Fire Tucson Mt Lemmon
Map of the Bighorn Fire. The red line was the perimeter at 10:31 p.m. MDT June 26, 2020. The green line was the perimeter about 48 hours before.
Bighorn Fire Tucson Mt Lemmon
Firing operation on Oracle Ridge at the Bighorn Fire. Inciweb photo June 23, 2020.

Bighorn Fire near Tucson grows to over 81,000 acres

Firing operations are being conducted to protect Saddlebrooke

(UPDATED at 7:53 a.m. MDT June 25, 2020)

Bighorn Fire Samaniego Peak
Bighorn Fire on Samaniego Peak, 6 p.m. June 24. Inciweb photo.

The Bighorn Fire north of Tucson was active Wednesday and Wednesday night. As firefighters worked on structure protection and fireline reinforcement in the Summerhaven and Willow Canyon areas, helicopters and air tankers successfully slowed fire spread and reduced fire intensity in the west fork of Sabino, Bird, and Rattlesnake canyons. Aerial firing operations in the Charouleau Gap area four miles east of Saddlebrook started around 5 pm.

(To see all articles about the Bighorn fire, including the most recent, click here.)

Bighorn Fire map Arizona Tucson
3-D map of the Bighorn Fire looking southeast. The red line was the perimeter at 9:46 p.m. MDT June 24, 2020. The green line was the perimeter about 24 hours before.

Firing operations also were carried out along the Catalina Highway near Spencer Peak and Spencer Canyons one mile east of Summerhaven and reinforced firelines near Dodge Wash two miles south of Oracle.

Bighorn Fire map Arizona Tucson
Map of the Bighorn Fire. The red line was the perimeter at 9:46 p.m. MDT June 24, 2020. The green line was the perimeter about 24 hours before.

A mapping flight Wednesday night determined that the Bighorn Fire had burned 81,702 acres, a 24-hour increase of over 7,000 acres.

Evacuations are in effect. For more information visit pima.gov/bighorn or pinalcountyaz.gov/emergencymanagement


(Originally published at 9:47 a.m. MDT June 24, 2020)

Bighorn Fire map Arizona
3-D map of the Bighorn Fire looking southeast. The green line was the perimeter June 19, 2020. The red line was the perimeter at 10:52 p.m. MDT June 23, 2020. The shaded areas represent intense heat detected by the mapping sensors in the fixed wing aircraft.

The Bighorn Fire has grown significantly in recent days to the north, west, and east. Since June 19 it has spread two miles to the west, five miles north, and three miles east.

During a mapping flight at 10:52 p.m. June 23 the fire was two miles south of Oracle, three miles south of Highway 77, and 2.5 miles southeast of Saddlebrooke. The fire has now burned 74,547 acres after starting from a lighting strike on June 5. About $21 million has been spent on managing the blaze.

A DC-10 Very Large Air Tanker drops retardant near Pontatoc Ridge on the Bighorn Fire north of Tucson, June 11, 2020. Photo by Tim Peterson.
A DC-10 Very Large Air Tanker drops retardant near Pontatoc Ridge on the Bighorn Fire north of Tucson, June 11, 2020. Photo by Tim Peterson.

On Tuesday structure protection and containment work supported by helicopter bucket drops focused around Mt. Lemmon, Summerhaven, and Willow Canyon. Low-intensity firing operations removed pockets of unburned fuels in these areas. Aerial firing operations were conducted south of Oracle. The efforts near Oracle Ridge and Rice Peak are intended to reduce the risk of uncontrolled fire growth to the north in the coming days.

Evacuations are in effect. For more information visit pima.gov/bighorn or pinalcountyaz.gov/emergencymanagement

Resources assigned to the fire Tuesday included 20 hand crews, 81 fire engines, 6 dozers, 19 water tenders, and 10 helicopters for a total of 876 personnel. The number of personnel assigned has decreased by 112 since Monday. There have been 4 minor injuries.

Bighorn Fire Arizona
Bighorn Fire as seen from Saddlebrook June 23, 2020. Photo by Molly Hunter.

Bighorn Fire north of Tucson grows to 42,798 acres

Firefighters have been conducting back burns out ahead of the fire

(Originally published at 10:09 a.m. MDT June 20, 2020)

3-D map of the Bighorn Fire
3-D map of the Bighorn Fire looking southeast at 10:12 pm MDT June 19, 2020.

The Bighorn Fire north of Tucson, Arizona grew by 5,740 acres Friday to bring the total up to 42,798 acres.

Firefighters have been conducting back burns out ahead of the fire which they hope will serve as barriers to fire spread south of the community of Oracle along Old Mount Lemmon Highway near Peppersauce. They have also been constructing firelines on the west side of the Catalina Highway.

(To see all articles on Wildfire Today about the Bighorn Fire including the most recent, click here.)

For information about evacuations in Pima County contact visit pima.gov/bighorn. In Pinal County check the Sheriff’s Office Facebook page.

Map of the Bighorn Fire
Map of the Bighorn Fire. by the Incident Management Team, June 20, 2020.

The map below shows the growth of the Bighorn Fire over a 24-hour period.

Bighorn Fire Map
The red line was the perimeter of the Bighorn Fire detected by a mapping flight at 10:12 p.m. MDT June 19. The yellow line was the perimeter about 24 hours before.

Firefighting resources assigned to the fire include 20 hand crews, 64 engines, 18 water tenders, 6 dozers, and 7 helicopters for a total of 894 personnel.

Bighorn Fire Tanker 910, a DC-10
Tanker 910, a DC-10 operated by 10 Tanker Air Carrier drops on the Bighorn Fire. N612AX. Ned Harris photo.

Bighorn Fire north of Tucson burns past Mt. Lemmon

The fire grew to over 31,000 acres Wednesday

(UPDATED at 12:10 p.m. MDT June 19, 2020)

Bighorn Fire Map
The red line was the perimeter of the Bighorn Fire detected by a mapping flight at 9 p.m. MDT June 18. The yellow line was the perimeter detected by a mapping flight about 24 hours before.

Thursday’s decreasing winds gave firefighters on the Bighorn Fire somewhat of a break, at least when compared with the difficult conditions on Wednesday that pushed the blaze northeast over Mt. Lemmon. Hand crews and personnel on fire engines were able to make progress, said Operations Section Chief Travis Mayberry.

(To see all articles on Wildfire Today about the Bighorn Fire including the most recent, click here.)

The lower wind speeds Friday could result in smoke being more visible in the communities near the fire. Weather forecasters expect temperatures of around 100 degrees with very low relative humidity.

Thursday night the fire was mapped at 37,058 acres, an increase of 5,850 acres in 24 hours.

Bighorn Fire Tanker 105 Tanker 10 BAe-146
Tanker 105 (foreground), an MD-87 (N295EA) operated by Erickson Aero Tanker, and Tanker 10, a BAe-146 (N472NA) operated by Neptune Aviation maneuver over the Bighorn Fire. Ned Harris photo.

Fire managers expect growth to the northeast in Cañada del Oro and Alder Canyons on Friday. Crews working south of Oracle and San Manuel will tie in containment lines today, in preparation for additional firing operations Friday evening. Firefighters on Mt. Lemmon are using an assortment of tools, including controlled burning, to protect the communities along the Catalina Highway.

As the high winds that had been keeping the fire burning on Samaniego Ridge and the top of Ventana Canyon subside, the fire may move downslope at a moderate pace. Firefighters will have to wait to engage some sections of the fire until after it transitions onto less steep terrain.


(Originally published at 1:35 p.m. MDT June 18, 2020)

map Bighorn Fire Arizona Tucson
3-D map of the perimeter of the Bighorn Fire mapped by fixed wing aircraft at 10:33 p.m. MDT June 17, 2020.

Since it started June 5 from a lightning strike the Bighorn Fire five miles north of Tucson has been adding less than 4,000 acres every day, until Wednesday when strong winds pushed it past Mt. Lemmon, growing by about 13,000 acres to bring the total up to 31,208 acres.

Firefighting resources assigned to the fire include 15 hand crews, 60 engines, 8 helicopters, 12 water tenders, and 6 dozers.

From the Incident Management Team Thursday morning:

“Today, fire managers anticipate the fire will move towards Charouleau Gap, depending on wind direction and temperatures. Fire crews and air support are in place preparing and widening fire lines for this expected spread of the fire. On Mt. Lemmon, the fire moved through Oracle Ridge and generated spot fires in Stratton Canyon. Expect highly visible smoke as those areas burn together today. Crews working overnight implemented controlled burns along the Catalina Highway corridor. Firing operations will continue today, if necessary, to protect values at risk.

“Air operations including fixed-wing airtankers were up early this morning, dropping water and fire retardant to slow the fire’s spread. Winds will continue to be a factor today, but less so than yesterday. The fire burning in the Ventana Canyon area and along Samaniego Ridge will be monitored by air support today. Minimal downslope backing of the fire is anticipated in that area. Crews will tie together the two containment lines north of the fire perimeter to protect the communities of Oracle and San Manuel.”

map Bighorn Fire Arizona Tucson
Perimeter of the Bighorn Fire mapped by fixed wing aircraft at 10:33 p.m. MDT June 17, 2020.
Bighorn Fire Arizona Tucson wildfire
Bighorn Fire, undated or credited Inciweb photo
progression acres Bighorn Fire Arizona Tucson
Bighorn Fire Progression. By the Incident Management Team.