Effective Windspeed (EWS)

Surface Fire Section

Surface Fire Behavior Worksheet
Effective Windspeed (EWS)
Surface Fire Behavior Lookup Tables
Surface Fire Behavior Nomograms and Nomographs
Flanking and Backing Fire Behavior
Vectoring Fire Behavior
Interpreting Expected Surface Fire Behavior
Surface Fire Size and Shape
Surface Fire References

EWS integrates the effect of winds and slope on a surface fire behavior estimate based on the fuel model the fire is expected to be burning in. These tables produce the resulting EWS when winds are blowing upslope.

For downslope and cross-slope winds, use the zero (0) mph row in the Midflame Windspeed (MFWS) column to estimate the Slope Equivalent Windspeed. It can be used as the MFWS in the lookup tables to produce slope vector fire behavior estimates for use in the Vectoring Fire Behavior section.

Effective Windspeed Adjustment Table. Use this series of tables to estimate windspeed when wind is blowing upslope. Factors include midflame windspeed, and slope. Using a midflame windspeed of zero (0) and the appropriate slope will allow user to estimate the slope equivalent windspeed.

PRINT FBFRG Effective Windspeed (EWS)

Page Last Modified / Reviewed:

2021-07-08