The National Weather Service is warning about "significant" fire hazards Friday.
The forecasting agency issued a fire weather watch for all of northeastern Illinois beginning at 10 a.m. Friday, and continuing through 7 p.m. in the evening.
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WATCH HEREThe NWS alert included notes about a red flag warning as well.
So what is the difference and what should you know?
What is a red flag warning?
According to the NWS, a red flag warning is issued when the combination of dry fuels and weather conditions support extreme fire danger. For northern Illinois and northwest Indiana, the red flag warning criteria includes sustained 20-foot winds of 20 mph or higher, relative humidity less than 25% and 10-hour fuel moisture at 8% per day.
"A red flag warning means that critical fire weather conditions are either occurring now, or will shortly," the NWS said in the alert issued Friday. A combination of strong winds, relative humidity and warm temperatures can contribute to extreme fire behavior."
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What is the different between a red flag warning and a fire watch?
According to NWS, the two alerts are relatively the same, but are based more on timing.
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SIGN UP "A Fire Weather Watch is issued up to 72 hours before the above conditions are expected to occur," the agency reported. "A Red Flag Warning is issued when the conditions above are expected to occur or are occurring within the next 24 hours."
When and where is the alert in effect?
That watch will include McHenry, Lake, DeKalb, Kane, DuPage, Cook, LaSalle, Kendall, Grundy, Will and Kankakee counties, according to NWS.
It is in effect from 10 a.m. CT Friday through 7 p.m.
"Very low relative humidity and strong winds will result in a significant fire weather threat late Friday morning into the early afternoon. Use extra caution when disposing of burning materials, if not altering or postponing burning plans altogether," the NWS wrote on X Thursday morning.
Sustained winds of 20-to-30 miles per hour are expected, with gusts up to 45 miles per hour, according to forecast models.
To complicate matters, more thunderstorms could develop on Friday, and lightning strikes could also cause fires to break out.
