Report: Chisholm wildfire entrapment investigation - FPInnovations ...

FIRE BEHAVIOUR FORECAST #2
Name of Fire: Chisholm LWF-63 Prediction for: 1700 May 27, 2001
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Fire Management District: Lac La Biche Shift Date: Sunday, May 27, 2001
Forecast Issued: 1900 May 26, 2001
Signed: Fire Behaviour Officer
Weather Summary:
RH recovery into the 70’s tonight with winds persisting E-SE 15-20 km/h and low temp of 10 degrees.
Sunday: Max temp 25%, Low RH 25%, Winds E-SE 25g50 km/h. Convective cloud development likely.
There is a cold frontal passage forecasted to occur over the fire Monday afternoon.
Fire Behaviour General:
C2: HFI 33,000kW/m/min, ROS 25 m/min, CFB 100%, Continuous crown
M2: HFI 21,000 kW/m/min, ROS 19 m/min, CFB 98%, High Intensity surface fire
O1b: HFI 4,800 kW/m/min, ROS 54 m/min, High intensity surface fire
Fuels are continuing to dry. All fuel types have reached a critical stage of dryness. This increase in wind
speed to 25 km/h will result in very intense burning conditions in all fuel types.
Specific:
Crown fire in all coniferous fuel types. Deciduous stands will support very vigorous surface fire with
torching of embedded conifer. Long range spotting due to wind speeds likely if significant excursions occur.
Erratic fire behaviour must be expected due to the extreme BUI values of 118 today.
Air Operations:
Smoke conditions should not be a problem in the AM as winds will be persisting overnight will limit the likely
hood of an inversion. Gusty surface winds and atmospheric instability will contribute to turbulent
conditions.
Safety:
LACES adherence is mandatory in all suppression operations. High spread rates in all fuel types are the
primary safety factor today. With the increase in wind speeds the probability of falling of root burned trees
also increases. Effective AM meetings with all fireline staff highlighting these / other safety issues must be
conducted.
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