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Black Diamond

Unit Information

Helena - Lewis and Clark National Forest
U.S. Forest Service
2880 Skyway Drive
Helena, MT 59602

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This incident is no longer being updated.

Black Diaond Fire Info MapImage options: [ Full Size ]

Mike Alma's Northern Rockies Incident Management Team 3 took command of the Black Diamond Fire or 6:00p.m. on Saturday, August 3, 2019. The lightning-caused fire was reported at about 2 pm on August 2, 2019. Upon report it was actively burning in dense timber and dense, dead timber/snags; within about 1/2-hour the fire had grown to nearly 20 acres.

Basic Information

Current as of
Incident TypeWildfire
Date of OriginFriday August 02nd, 2019 approx. 02:00 PM
Incident DescriptionUnknown
Coordinates46.954 latitude, -112.426 longitude

Current Situation

Total Personnel149
Size36 Acres
Fuels Involved

Timber; Snags

Significant Events


isolated Torching



Significant activity has decreased as mop-up efforts have been successful thus far. Potential for undetected spots remains as the terrain influenced winds produce flare-ups. Numerous spots near to fire perimeter have been slow to develop, but also difficult to locate in heavy dead and down material. Terrain influenced winds have contributed to spotting. Fire has spread primarily by burning in the beetle killed surface fuels and then by a torching/spotting cycle, Grasses and shrubs appear to green to carry fire by themselves but the heavy component of 1000-hr fuels is causing spread.


Planned Actions

Continue aviation and ground operations to bolster containment and confine strategy.

Projected Incident Activity

Black Diamond Fire engulfed by emerging Horsefly Fire

Current Weather

Weather Concerns

Current: Warm and dry conditions occurred again today under a dry westerly flow aloft. General winds were from the west today with a few gusts to around 20mph at exposed ridgetops, while lighter terrain driven winds prevailed on slopes and valleys.

Predicted: A westerly wind flow will prevail through most of this week as high pressure remains anchored over the southwest U.S. and Great Basin. An initially limited amount of moisture will work north into the region, bringing a slight chance of thunderstorms Tuesday and Wednesday with a greater chance of thunderstorms Thursday and Friday. Cloud-cover will also increase as the week progresses, bringing some moderation to temperatures and humidity

Related factors: Continued dry conditions and rebuilding high pressure will result in only moderate humidity recovery at midslopes and ridgetops. As thunderstorm activity increases later this week, concern for outflow wind gusts and new fire starts increases.