(MCT) — The National Weather Service has issued a "red flag warning" for northern Illinois and northwest Indiana from noon Central Time until 8 p.m. because warm, dry and windy weather "will become favorable for rapid growth of wildfires."
Red flag warnings are common in the spring and fall months, before and after the growing season, when dry cold fronts are followed by warm, windy weather, said weather service meteorologist Kevin Birk. Although the warm spring has caused grass and other plants to burst out much earlier than usual, there's still a lot of dry, dead plant material around, Birk said.
Meanwhile, the National Weather Service warned outlying areas, including McHenry and Kane counties, are likely to experience freezing temperatures down to as low as 29 degrees for several hours overnight. That may affect plants that have bloomed or sprouted earlier than usual because of the mild spring, forecasters said.
Birk said brush fires are still a concern, despite the early sprouting of vegetation.
"I don't want to say that it's not dry out there, because although some grasses have sprouted, there's still a lot of fuel out there," Birk said.
With relative humidity as low as 15 to 25 percent, "a combination of strong winds, low relative humidity, and warm temperatures will create explosive fire growth potential," according to the weather service's warning.
This spring has seen several red flag warnings because of the record-breaking warm March weather and dry conditions, Birk said.
The warning today includes most of northern Illinois and northwest Indiana, with the exception of some counties west of Rockford and Interstate 39.