Sunday's storms downed tree limbs and caused power outages across the region, with up to 2,500 NIPSCO customers without power at any one time.
The National Weather Service reported wind gusts of up to 51 mph at Gary/Chicago International Airport and temperatures falling rapidly from the low 70s at mid-afternoon into the 40s early in the night.
At one point late in the afternoon, up to 1,000 NIPSCO customers in Crown Point were without power. Most had power restored by early in the night, said NIPSCO spokesman Larry Graham. By that time, Gary and Griffith were some of the areas hardest hit.
That was the pattern throughout late afternoon and early evening, as one hard-hit area would be restored and then others would sustain severe wind damage. NIPSCO crews planned to work through the night and into the morning, but it was difficult to say when all customers would be restored, Graham said.
"As long as the wind gusts continue, we could have new outages throughout the night," Graham said.
There were also scattered outages across ComEd's Illinois territory, according to its power outage webpage.
On Sunday afternoon, the National Weather Service issued warnings of strong thunderstorms capable of producing gale-force winds and a severe maritime warning for coastal waters from Chicago to Gary. Weather radar showed a line of thunderstorms advancing across the area.
However, Coast Guard stations in Chicago and Michigan City reported no incidents on Lake Michigan as of late afternoon.
In Schererville, police and public safety personnel were checking on a downed tree in the 6900 block of 75th Avenue late in the afternoon and there were scattered power outages around town, according to dispatchers. In Lake Station, police checked on a report of a downed power line at a residence.
The forecast from the National Weather Service for Monday is for mostly sunny skies and temperatures reaching a high of only 57 degrees. Winds will be from the northwest with gusts as high as 20 mph.