Fog patches dissipated Thursday evening, but Environment Canada issued a special weather statement for much of southwestern Ontario.
The national weather agency said significant rain was in the forecast for Sarnia-Lambton, Chatham-Kent, Windsor-Essex, London and Middlesex County, southern Huron County, southern Perth County, Oxford County, and Elgin County Thursday night and into Friday.
Anywhere from 15 to 25 millimetres of rain is in the forecast, with locally higher amounts possible overnight, and water ponding is also possible in some spots.
Environment Canada said rain will taper off on Friday.
The frozen ground will have a reduced ability to absorb this rainfall, and localized flooding may occur in areas with poor drainage.
For information concerning flooding, consult your local conservation authority or Ontario Ministry of Natural Resources and Forestry office.
Residents can visit www.Ontario.ca/floods for the latest details.