Active AlertsGarden Prairie, IL

THE NATIONAL WEATHER SERVICE HAS ISSUED TORNADO WATCH 109 IN EFFECT UNTIL 10 PM CDT THIS EVENING FOR THE FOLLOWING AREAS IN ILLINOIS THIS WATCH INCLUDES 8 COUNTIES IN NORTH CENTRAL ILLINOIS BOONE DE KALB LEE OGLE WINNEBAGO IN NORTHEAST ILLINOIS KANE LAKE IL MCHENRY THIS INCLUDES THE CITIES OF ALGONQUIN, AURORA, BELVIDERE, BUFFALO GROVE, BYRON, CRYSTAL LAKE, DEKALB, DIXON, ELGIN, GURNEE, MCHENRY, MUNDELEIN, OREGON, ROCHELLE, ROCKFORD, SYCAMORE, WAUKEGAN, AND WOODSTOCK.

What: Flash flooding caused by excessive rainfall is possible.
Where: Portions of Illinois, including the following areas, Boone, Central Cook, De Kalb, DuPage, Eastern Will, Kane, Kendall, Lake IL, McHenry, Northern Cook, Northern Will, Ogle, Southern Cook, Southern Will and Winnebago and northwest Indiana, including the following area, Lake IN.
When: Until 6 AM CDT Wednesday.
Impacts: Creeks and streams may rise out of their banks. Flooding may occur in poor drainage and urban areas. Roads and streets may be flooded.
Additional Details: - An area of thunderstorms with rain rates up to one to two inches per hour is expected to move through the area this evening through the overnight hours. Elevated soil moisture due to recent rainfall is expected to increase the susceptibility to flash flooding. - http://www.weather.gov/safety/flood

A Flood Watch for flash flooding means rapid-onset flooding is possible, but not yet certain, based upon the latest forecasts. Flash flooding is a dangerous situation. Persons with interests along area rivers, creeks, and other waterways should monitor the latest forecasts and be prepared to take action should flooding develop.

At 828 PM CDT, severe thunderstorms were located along a line extending from near East Troy to near Capron to near Winnebago, moving east at 40 mph.
Hazard: 70 mph wind gusts.
Source: Radar indicated.
Impact: Expect considerable tree damage. Damage is likely to mobile homes, roofs, and outbuildings. These severe storms will be near Belvidere, Loves Park, Harvard, Poplar Grove, Candlewick Lake, Cherry Valley, Capron, and Timberlane around 835 PM CDT. Hebron around 840 PM CDT. Woodstock, Marengo, Genoa City, and Richmond around 845 PM CDT. Twin Lakes, Spring Grove, Wonder Lake, and Bull Valley around 850 PM CDT. Crystal Lake, McHenry, Fox Lake, Johnsburg, and McCullom Lake around 855 PM CDT. Lake in the Hills, Huntley, Lakemoor, Lakewood, Pistakee Highlands, and Prairie Grove around 900 PM CDT. Island Lake and Oakwood Hills around 905 PM CDT. Algonquin, Cary, Fox River Grove, and Port Barrington around 910 PM CDT.

A Tornado Watch remains in effect until 1000 PM CDT for north central and northeastern Illinois. Remain alert for a possible tornado! Tornadoes can develop quickly from severe thunderstorms. If you spot a tornado go at once into the basement or small central room in a sturdy structure. Prepare immediately for damaging winds and deadly cloud to ground lightning. Seek shelter inside a well-built structure. Stay away from windows.

Waves of showers and thunderstorms are expected this evening through the end of the week. Urban and river flooding will be possible. Atmospheric conditions are favorable for some thunderstorms to have rainfall rates in excess of 1 to 2 inches per hour tonight and tomorrow. In addition, some rivers and streams remain elevated from recent rainfall and soil moisture is elevated across most of northern Illinois and northwestern Indiana. In urban and poor drainage areas isolated flooding of roadways, creeks, and streams may occur with areas of heaviest rainfall. Widespread rainfall may also lead to river rises and possible flooding, in particular along already elevated rivers such as the Fox, Des Plaines, and Kankakee. Additional chances for rainfall are expected to continue through the remainder of the week. This outlook means that elevated water levels and potential impacts are possible, but not yet certain. Persons should closely monitor forecasts including the possibility of flood watches, warnings, and advisories. This product will be updated by tomorrow morning.