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 Fire Weather Watches and Red Flag Warnings (RFW, FXUS63 KLMK)

Fire Weather Watches are used to alert users of the possible development of a Red Flag event in the near future. This period covers from 12 to 72 hours in advance of the event.  A Red Flag event is defined as an event where ten-hour fuel stick moisture must be 8% or less, along with afternoon relative humidity levels 25% or below, and 20-foot winds are expected to exceed 15 mph.  All three requirements must be met.

Red Flag Warning are issued to warn an impending or ongoing Red Flag event. A Red Flag Warning will be issued immediately when Red Flag conditions are met.  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 four hours.

Product Example >> Current Product

 

FXUS63 KLMK 031458
RFWSDF

FIRE WEATHER WATCH/RED FLAG WARNING
NATIONAL WEATHER SERVICE LOUISVILLE KY
900 AM EDT TUE SEP 3 2002

.A RED FLAG WARNING HAS BEEN ISSUED FOR A PORTION OF EAST CENTRAL
KENTUCKY FOR GUSTY WINDS THIS AFTERNOON.
$$

.DISCUSSION...AN AREA OF LOW PRESSURE LOCATED OVER THE NORTHERN
PLAINS WILL MOVE RAPIDLY EAST INTO THE GREAT LAKES REGION BY TUESDAY
AFTERNOON.  SOUTHERLY WINDS ARE EXPECTED TO INCREASE ACROSS THE REGION
THIS AFTERNOON AND THE WINDS WILL EXCEED RED FLAG CRITERIA OVER A
PORTION OF EAST CENTRAL KENTUCKY.
THE CONDITIONS SHOULD IMPROVE AFTER 800 PM EDT AS WIND SPEEDS
DECREASE TO LESS THAN 15 MPH.  HOWEVER...ANOTHER RED FLAG WARNING
MAY NEED TO BE ISSUED ON WEDNESDAY.
PLEASE ADVISE THE APPROPRIATE OFFICIALS OR FIRE CREWS IN THESE AREAS
OF THIS RED FLAG WARNING.

$$
 
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