DEFINITIONS OF FIRE WEATHER WATCH /RED FLAG WARNING:

The following conditions must be met to issue a Fire Weather Watch or a Red Flag Warning in Ohio:

A. Ten hour fuels must be at 8% moisture or less and expected to remain at that level for 2 or more days.

B. The afternoon and evening relative humidity levels are expected to fall to 25% or lower and the 20 foot sustained winds are expected to exceed 15 mph (13 knots) for at least 2 hours.


The following conditions must be met to issue a Fire Weather Watch or a Red Flag Warning in extreme Northwest Pennsylvania:

A. Ten hour fuels must be at 15% moisture or less and expected to remain at that level for 2 or more days.

B. The afternoon and evening relative humidity levels are expected to fall to 30% or lower and the 20 foot sustained winds, sustained or frequently gusting, at or above 20 mph (17 knots).


"Fire Weather Watch" is used to alert the user to the possible development of a Red Flag event in the near future. This could be up to 72 hours in advance.

"Red Flag Warning" will be issued to warn the user of an impending or on-going Red Flag event. A Red Flag Warning will be issued immediately when Red Flag Conditions are occurring. Otherwise, it will be issued for impending Red Flag Conditions when there is a high degree of confidence that conditions will develop and the forecast time of onset for the event is less than 24 hours from the forecast issuance time.