Timber (Litter and Understory) Brush (2 feet) Medium Logging Slash

Red fir fuel type with montane shrub and brush understory interspersed with pockets of non-burnable fuels in granite rock outcrops. Fir trees are large diameter, over 100 ft. tall, and suffer from insect and disease mortality, leading to a significant snag component with large amounts of heavy dead and down coarse woody debris. Most active fire behavior has come from the dense, closed canopy red fir stands, where torching and isolated crown fire pockets have also contributed to spotting. Fuels in 2017 fire footprints have less closed canopy but contain significant dead and down with standing snags, increasing spotting potential. Surface spread rates are lower in the Empire Fire (2017) Footprint, but spotting continues to drive spread. Montane shrubs and brush in the understory are generally available to burn but are not at critical fuel moisture levels. Heavy dead and down fuels are dry, with fuel moisture in 1,000 hr. fuel around 12%.

Moderate, Spotting, Creeping, Single Tree Torching

Continued creeping fire behavior remains present in areas with no established direct control lines. Large dead and down interior fuels continue to consume readily. Spot fires remain a persistent threat and are the primary drivers of the fire spread outside the current fire perimeter. Due to the large amount of standing dead trees, within the current burn scar from previous fires, isolated interior single tree torching continues to occur. Fuels adjacent to the fire perimeter remain receptive to new ignitions and will support additional fire spread if ignited.

Strengthen primary and contingency lines. Employ rotary-wing aviation assets to check fire spread, moderate flame lengths to thresholds suitable for direct attack. Crews may conduct firing operations as appropriate to bring fire to containment lines from Division M/Q break to the east and south toward Division T. Division Q and T are installing direct control lines where safe to do so. 

In Branch 5 Division A and Z are patrolling and mopping up to extent necessary to keep the fire in its current footprint. In Branch 10, Division F, K, and M are patrolling, mopping up and reinforcing control lines as necessary to keep the fire in its current footprint.

12 hours: Overnight heavy interior fuels will continue to consume. With lack of pronounced overnight winds conditions are not favorable for fire spread. Any potential spread is further suppressed by the presence of an overnight inversion.

24 hours: Fire spread will generally be terrain driven if ember cast establishes a spot fire outside the current perimeter. Continued spread eastward toward Ostrander Lake and East from H-17 are possible on the eastern flank. Fire will continue to back down toward Alder Creek on the western flank in areas absent of direct control lines. The risk from spot fires and interior standing dead trees falling across control lines remain.

48 hours: Fire spread will generally be terrain driven if ember cast establishes a spot fire outside the current perimeter. Continued spread eastward toward Ostrander Lake and East from H-17 are possible on the eastern flank. Fire will continue to back down toward Alder Creek on the western flank in areas absent of direct control lines. The risk from spot fires and interior standing dead trees falling across control lines remain.

72 hours: A system change in the current weather pattern is anticipated to begin. There are strong indications of a marked increase in wind occurring during this time of change. Strong winds may pose a direct threat to established control lines. Interior fuels may exhibit active fire behavior, due to increased ventilation, where heat sources remain adjacent to unburned fuels. Spot fires may occur readily. This may lead to fire spread beyond the current perimeter. Active fire spread may occur, where alignment of slope and wind exist, should spot fires become well established beyond current control lines.

Anticipated after 72 hours: A system change in the current weather pattern is anticipated to begin. There are strong indications of a marked increase in wind occurring during this time of change. Strong winds may pose a direct threat to established control lines. Interior fuels may exhibit active fire behavior, due to increased ventilation, where heat sources remain adjacent to unburned fuels. Spot fires may occur more readily. This may lead to fire spread beyond the current perimeter. Active fire spread may occur, where alignment of slope and wind exist, should spot fires become well established beyond current control lines. After this system change, occurring over one to two days, conditions are anticipated to moderate significantly due to substantially cooler and more moist weather.

Observed: Mostly sunny conditions are occurring today across the fire area today along with very warm temperatures in the 60s and 70s and minimum relative humidity in the 20-30% range. Terrain driven winds, mostly from the southwest to west 3-8 mph with gusts 10-18 mph are being observed. 

12-Hour Overnight: Clear with typical drainage winds, mostly from the east. Relative humidity recoveries are likely to be 40-60% with low ranging from the mid 30s in high elevation valley could spots to near 60 in mid-elevation thermal belts. Smoke will again settle into the drainages in and around the fire area. 

24-72 Hour Forecast: Warm and dry conditions with similar temperatures, relative humidity, and winds to the short term are expected to continue Wednesday and Thursday as high pressure continues. Low pressure approaching the coast will begin to weaken the high Friday leading to a slight uptick in afternoon/evening southwest winds. 

Extended (After 72 Hours): There is high confidence in a significant weather change to cooler weather this weekend into early next week. Temperatures are likely to decrease by 15-25 degrees with diurnal temperature ranges becoming smaller. A period of increased mixing and moderate to strong, gusty southwest winds are likely Saturday into Sunday with a slight chance of measurable precipitation Sunday increasing to a 30-50% chance of showers Monday.