Arctic Air Mass Lingers for Areas of the East; Critical Fire Weather for the Plains; Active Weather Pattern for Hawaii

Arctic air lingers for the east, however, winds will slowly subside and a slow moderating trend starts during the week. Moisture continues to provide rainfall and higher elevation snow for the Pacific Northwest, northern California and northern Rockies through Monday. For the State of Hawaii, dangerous surf conditions with strong winds and heavy rainfall will impact the islands through Monday. Read More >

Fire Weather Watch/Red Flag Warning Criteria

Specific conditions must be met for a Fire Weather Watch and/or a Red Flag Warning to be issued. These conditions are as follows:

1. KBDI greater that or equal to 600, and

2. Two minute ASOS winds greater than or equal to 17 kts (20 mph), or 20 foot winds greater than or equal to 14 kts (16 mph), and

3. Minimum relative humidity of less than 60% in one or more observations, and

4. Low 10-hr fuel moisture, typical less than 13.

5. Monthly precipitation less than two inches with a decrease and/or cessations of percolation (dew)can signal the onset of the fire season. Forecaster judgment must be used in the watch/warning decision making process.