...A period or two of heavy rainfall possible across the area through Friday morning...
As a warm front lifts north and an upper level disturbance moves over the area late tonight into Thursday...scattered thunderstorms are expected to develop across portions of the area. Given the very moist air mass in place over the region...any thunderstorms will be capable of producing torrential downpours. A second round of thunderstorms is possible Thursday night...and this could again lead to torrential downpours...along with the possibility of flooding. At this time...confidence is low as to where the most widespread thunderstorm activity will focus. However...the ingredients are in place for at least minor Urban and Small Stream flooding for parts of the area late tonight into Thursday morning and again Thursday night. Concern exists for localized flash flooding over areas that experience continued thunderstorm activity for a longer period of time.
Stay tuned to later forecasts and the possible issuance of a Flash Flood Watch at weather.Gov/Chicago.
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