FLAGSTAFF, Ariz. (AP) — Authorities are warning that much of northern Arizona will have dangerous wildfire conditions this weekend.

The National Weather Service issued a fled flag warning for the region from late morning to early evening Saturday and a fire weather watch for the equivalent period on Sunday.

A red flag warning means that critical fire weather conditions are either occurring or are imminent, and forecasters say a combination of strong winds and low relative humidity can contribute to extreme fire behavior.

The weather service says peak wind gusts of 40 mph (64 kph) are forecast Saturday at Flagstaff, Seligman and Grand Canyon Village, 41 mph (66 kph) at Williams and 32 mph (51 kph) at Prescott and Show Low.