Two rounds of severe storms swept through Lake County on Monday, July 27, knocking out power to tens of thousands of residents and shutting down the Lake Bluff Public Library for the entire day. The library at 123 E. Scranton Ave. reopened at 10 a.m. Tuesday, July 28, after power was restored overnight, the library said on its website.

Power came back overnight.

But the scope of Monday's outages was massive. By 1:40 p.m., more than 200,000 ComEd customers across the Chicago region had lost power, according to ComEd data reported by the Chicago Tribune. That was before the second round of storms arrived. By 9 p.m., the ComEd outage map showed over 280,000 customers without electricity regionwide, according to WGN-TV. The Lake & McHenry County Scanner, a local emergency-services social media account, reported tens of thousands of those outages were concentrated in Lake County.

Two rounds of severe weather

The storm system struck in two waves. The first hit in the late morning and early afternoon, producing quarter-sized hail and damaging winds. A second, stronger round followed after 4 p.m., according to the National Weather Service.

"We already have ongoing storms. We have some reports already of quarter-sized hail or even slightly larger," National Weather Service meteorologist Kevin Doom told the Chicago Tribune on Monday as the first round moved through the region. Gusts up to 70 mph were recorded at Midway Airport, and as much as three inches of rain fell there by 4:30 p.m., according to NWS meteorologist Eric Lenning.

Lake Bluff library closed all day Monday

The Lake Bluff Public Library lost power Monday and closed for its full scheduled hours of 10 a.m. to 6 p.m. The library posted a notice directing residents to check its website for updates during the outage. By Tuesday morning, the library confirmed power had been restored and doors would open on the normal schedule.

The library can be reached at 847-234-2540.

What's next for residents

The National Weather Service forecast dry conditions through at least Friday, July 31, giving utility crews and public works departments a clear window for restoration and cleanup. ComEd said crews would begin restoring power as soon as conditions were safe but did not provide a specific timeline for Lake County.

Residents who still lack power or see downed lines can contact ComEd at 800-334-7661 or through the ComEd website and mobile app. For Lake Bluff library hours and service updates, visit lakeblufflibrary.org.