YOSEMITE — Five fires continue to burn in the wilderness areas of Yosemite National Park, with a strong stable air mass over the area bringing warmer than normal temperatures and lower humidity.

This has contributed to more fire activity and more smoke production as the 8,000-acre Empire Fire moved through some heavier fuels. The smoke has been flowing into Yosemite Valley and is unable to lift out due to the stagnation.

There was a brief respite last Friday and Saturday, but the warm pattern is expected to continue throughout the week.

There is potential for periods of heavier smoke to occur during certain times in Yosemite Valley throughout this warm trend. Dense smoke can aggravate symptoms for sensitive persons and activity should be reduced or avoided.

Fire Managers are working with the local Air Quality Districts and will be monitoring smoke impacts to the park and local communities, say park officials.

Current fires in Yosemite National Park:

Empire

Discovered: 7/31/17

Location: 1 mile east of Yosemite Ski and Snowboard Area and 3/4 mile south of Glacier Point Road

Size: 8,094 acres

Cause: Lightning

Containment: 85%

Fuels: Red fir

​The fire is moving east deeper into the wilderness, burning into the old “Meadow Fire” footprint in the Illiouette drainage producing moderate smoke. This area has shrubs and heavier dead and down fuel. The trajectory of the fire will likely take it in the direction of sparser fuels later in the week, which should reduce smoke production. The fire is visible from vistas along the Glacier Point Road.

South Fork

Discovered: 8/13/17

Location: .75 miles east of the community of Wawona

Size: 7,564 acres

Cause: Lightning

Containment: 90%

Fuels: Mixed conifer and red fir

The fire remains quiet near the community of Wawona on the west and south flank. Sections of the north flank and the entire east flank are continuing to burn into the wilderness. Fire activity has been minimal this week.

Starr King

Discovered: 8/2/17

Location: N 37° 42.965′ x W 119° 29.588′ at approximately 7,800 feet elevation

Size: 70 acres

Cause: Lightning

Spread Potential: Low/ Moderate

Fuels: Red fir/ Lodgepole Strategy: Monitor

Visible from the Glacier Point Road.

Porcupine

Discovered: 8/2/17

Location: N 37° 49.336′ x W 119° 34.720′ at approximately 8,154 feet elevation off Tioga road.

Size: 9 acres

Cause: Lightning

Spread Potential: Low

Fuels: creeping, burning in duff and dead and down in Lodgepole Pine/ Red fir

Strategy: Monitor

Visible burning next to the Tioga Road.

Ribbon

Discovered: 9/26/17

Location: 37 45.3 by119 38.5 at approximately 8,154 feet elevation off Tioga Road.

Size: 2 acres

Cause: Lightning

Spread Potential: Low

Fuels: Low brush

Strategy: Monitor

Visible from Sentinel Dome and Glacier Point ​

​​These fires are burning in designated wilderness. Lightning-ignited fires in wilderness areas are often allowed to burn if they do not threaten developed areas.

“The Yosemite Wilderness is a fire adapted ecosystem where past fire suppression has resulted in unnaturally high fuel levels,” say fire officials. “Allowing fires to burn unimpeded produces a healthier, more diverse forest and helps reduce the severity of future fires.”

For more information on Yosemite fires, visit https://www.nps.gov/yose/blogs/fireinfo.htm