People near streams and creeks, as well as those living in low lying areas in Oak Lawn, should keep watch for flash floods.
The National Weather Service has put a flood watch in effect for Cook and Will counties, as well as other northern Illinois areas, until Monday morning, as of 11:40 a.m. Sunday.
The NWS reports:
SLOW MOVING THUNDERSTORMS MAY PRODUCE VERY HEAVY RAINFALL WITH STORM TOTAL RAINFALL AMOUNTS BETWEEN 1 AND 3 INCHES PROBABLE...AND ISOLATED HIGHER AMOUNTS POSSIBLE.
FLOODING OF CREEKS...STREAMS...LOW LYING AREAS...ROADS...AND URBANIZED AREAS IS POSSIBLE IF THESE RAINFALL AMOUNTS MATERIALIZE.
Rain is expected to continue through the night until Monday morning.
A moist air mass in the air has led to an atmosphere that is “supportive of storms,” according to the NWS.
The storms are moving slowly east.