Storm Report: Potential for Large Hail, Damaging Winds

Update: April 9, 2015, at 2 p.m.

A tornado watch has been issued in Cook and other counties, effective until 11 p.m. Thursday, according to the National Weather Service.

A tornado watch means conditions are favorable for tornado development. During a watch, people should be prepared to move a safe place if threatening weather approaches.

--

Posted April 9, 2015, 12:22 p.m.

The National Weather Service issued a hazardous weather outlook Thursday morning for Cook, DuPage and other counties, as rain and thunderstorms move though Illinois.

The greatest threat of severe thunderstorms Thursday is between 2 and 9 p.m., according to the National Weather Service, and thunderstorms may continue through the evening.

Some thunderstorms could produce:

• Locally heavy rainfall resulting in localized flooding
• Hail up to the size of half dollars
• Damaging winds up to 70 mph
• Frequent cloud-to-ground lightning
• Possibly an isolated tornado

Have you seen any of these things? Send updates and photos to morgan.searles@patch.com.

The main concern with this storm system is the potential for large hail and damaging winds, and it’s possible an isolated tornado could appear.

The Oak Lawn Emergency Management Agency has advised residents to secure loose items outside and to prepare a working flashlight with extra batteries and a portable radio, in case of power loss.

The ComEd outage map doesn’t currently show any power outages in Oak Lawn, but below you can find the methods for reporting a power outage or brownout.

• Call ComEd at 1-800-334-7661
• Click here to report the outage online
• Use the ComEd Mobile App
• Subscribers to ComEd outage alerts can text “OUT” to 26633

A warm, moist airmass is moving through the region, but a cold front is expected to sweep through this evening. There’s a chance of more thunderstorms Sunday night, Tuesday and Wednesday, according to the outlook.

Detailed weather forecast for Oak Lawn, via the National Weather Service

Thursday afternoon: Showers and thunderstorms likely. Some of the storms could be severe. Areas of fog before 1pm. Otherwise, cloudy, with a high near 74. Breezy, with a south southwest wind 15 to 20 mph, with gusts as high as 25 mph. Chance of precipitation is 70%. New rainfall amounts between a quarter and half of an inch possible.

Thursday night: Showers and thunderstorms likely, mainly before 11pm. Some of the storms could be severe. Cloudy, then gradually becoming partly cloudy, with a low around 45. Breezy, with a west southwest wind 20 to 25 mph, with gusts as high as 35 mph. Chance of precipitation is 70%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

Friday: Mostly sunny, with a high near 59. Breezy, with a west wind around 20 mph, with gusts as high as 30 mph.

Friday night: Partly cloudy, with a low around 37. West northwest wind 5 to 15 mph, with gusts as high as 25 mph.

Saturday: Sunny, with a high near 60. West wind around 5 mph.

Saturday night: Mostly clear, with a low around 42.

Sunday: Mostly sunny, with a high near 66.

Sunday night: A chance of showers and thunderstorms. Mostly cloudy, with a low around 47.

Monday: Mostly sunny, with a high near 66.

Monday night: Partly cloudy, with a low around 50.

Tuesday: A chance of showers and thunderstorms. Mostly cloudy, with a high near 70.

Tuesday night: A chance of showers and thunderstorms. Mostly cloudy, with a low around 54.

Wednesday: A chance of showers and thunderstorms. Mostly cloudy, with a high near 68.

» LEARN MORE:

• What does Code Orange signify? Understand the Severe Weather Categories

• Voice of a Tornado, 1967 Oak Lawn