UPDATE: Runoff expected from warm temperatures and rain (flood bulletin, January 11-14, 2018)

Flood Watch (issued January 11, 2018 at 2:30 pm; valid until January 14, 2018)

Between 20 and 30 mm of rain are forecast for today through Friday morning, combined with air temperatures remaining fairly steady at 8 °C, before dropping below freezing on Friday morning. Snowpack water equivalent (the depth of water contained in the snow pack), is estimated between 40 and 50 mm across the watershed, with fairly uniform distribution.

The forecast warm temperatures and rain are expected to produce runoff across the watershed. No serious flooding is anticipated at this time, but Flood Coordinators should expect bank full conditions in most areas, and water out of banks in areas that traditionally flood in the spring, such as Harris Park and Gibbons Park in London. Peak flows are expected to occur starting Friday afternoon and continuing into Saturday in downstream areas. Water levels will remain elevated over the weekend.

Temperatures are forecast to drop to below freezing on Friday, return to the negative double digits by Saturday morning, and remain below freezing for the rest of next week. Much of the current snowpack will be depleted by the end of this event.

Municipal staff should monitor local drainage problem areas where snow and ice may have covered catch basins. Smaller rural watercourses may have been drifted in by snow which, during a runoff event, can block flows and back up water onto adjacent lands, resulting in localized flooding problems.

Residents are reminded to use extreme caution near all watercourses, and keep children and pets away. Ice is unstable and thin, streambanks are slippery and the water is very cold.

The UTRCA’s flood control reservoirs at Fanshawe, Wildwood and Pittock Conservation Areas are at seasonal levels. UTRCA officials are monitoring the situation, and will report on any changing conditions if necessary.

See Thames River water level information

Contact: Eleanor Heagy, Communications Specialist

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