UPDATE 11:45PM: Scattered showers and thunderstorms continue to roam some of Chicago’s southern suburbs as well as northwest Indiana at this hour. All of the activity is below severe limits and will remain that way throughout the rest of the night. No additional watches or warnings are expected. Rain has cleared Wrigley Field, and it appears the Pear Jam concert will resume shortly. Most of the shower and thunderstorm activity should be confined to areas along and south of the I-80 corridor for the remainder of this Friday night.
UPDATE 10:30PM: A hail producing thunderstorm was located over Wheaton at 10:25PM drifting southeast toward Hinsdale, Downers Grove and Westmont. No warnings are in effect at this time (10:30PM) but up to penny sized (0.75″) hail is possible with this cell.
At 10:25PM, pea to marble sized hail was reported in Wheaton and West Chicago.
BELOW: Radar in hail detection mode (vertically integrated liquid) indicates the presence of hail over western DuPage county.
UPDATE 10:15PM: The thunderstorm that is moving through the city of Chicago is weakening rapidly at 10:15PM as it moves out over Lake Michigan. Unfortunately there is another trailing thunderstorm over the western suburbs that will be clipping portions of Du Page and southern Cook County in the next hour. All of the thunderstorms are currently below severe limits.
UPDATE 10:05PM: The Severe Thunderstorm Warning issued for northern Cook and portions of Du Page counties was allowed to expire at 10:00PM. The storm that prompted the warning has decreased slightly in intensity. Radar is still showing gust winds of 40-50mph are still possible.
UPDATE 9:53PM: Strong winds are being reported across some north and northwest suburbs of Cook County as well as the city. Scattered power outages have occurred in Morton Grove as well as Chicago’s north side. The latest radar scans indicate that the winds associated with the severe thunderstorm over northern Cook County have decreased in intensity slightly
UPDATE 9:32PM: A wind gust of 55mph was clocked at O’Hare Airport at 9:30PM. No significant damage has been reported as of this time.
UPDATE 9:25PM: A wind gust of 55-60mph was estimated (not actually measured) in Hoffman Estates at 9:14PM.
UPDATE 9:20PM: The National Weather Service has issued a Severe Thunderstorm Warning for portions of northern Cook and DuPage counties until 10:00PM. The main threat from this storm will be damaging winds of 60mph. Frequent lightning and heavy rain is also expected in the path of the warned storm.
A line of thunderstorms drifting southeast toward Chicago has intensified, prompting the National Weather Service to issue a warning. Details on the warning can be found here.
The Pearl Jam concert at Wrigley Field has been stopped due to the approaching storm.
BELOW: Radar in velocity/wind detection mode shows a pocket of 50mph+ winds over Elk Grove Village, headed for O’Hare and northern Cook County.
UPDATE 8:55PM: A broken line of thunderstorms continues to drift slowly southeast from Chicago’s northern suburbs. These storms are expected to arrive in on the city and western suburbs between 9:30PM and 11:00PM. Frequent cloud to ground lightning as well as heavy downpours are likely with the passage of these storms.
High resolution radar data indicates these storms are below severe limits with wind gusts of 45mph or less.
UPDATE 7:55PM: A line of slow moving showers thunderstorms continue to trek over Chicago’s northern suburbs at 7:55PM. These storms are producing heavy downpours as well as frequent cloud to ground lightning. Radar rainfall estimates indicate around one inch of rain has fallen over some portions of McHenry and Lake counties. There are no severe weather warnings or watches in effect at this time other than a Marine Warning for portions of southern Lake Michigan.
7:08PM: A Marine Warning has been issued for portions of southern Lake Michigan offshore from Winthrop Harbor to Wilmette.
6:55PM: Weather radar continues to show showers and thunderstorms slowly developing over Chicago’s northern suburbs from Belvidere to Round Lake.
As of 6:55PM these storms are not severe, and there are no severe weather watches or warnings in effect for the Chicago area. These storms are being monitored by the WGN Weather Center for intensification.