The Lower Thames watershed is currently experiencing a brief warm spell. Daytime temperatures are expected to reach around 5 C today and could reach 7 C tomorrow before dropping back below freezing on Friday. Forecast for tomorrow afternoon through the overnight are calling for up to 20 mm of rain. There is currently somewhere around 20 mm of water stored in the snowpack, although this varies around the watershed.
The snow has the capacity to absorb some rainfall and if small amounts of rainfall appear, the rain may not have any impact on water levels throughout the watershed. However, if the larger amounts of rainfall appear, the snow will melt and that water will add to the rainfall. This combination of rain and melted snow would cause water levels on the region’s smaller local watercourses to rise. There would be the possibility that the Indian-McGregor Creek Diversion Channel in Chatham would need to be operated on Friday and the Conservation Authority is preparing for that. As there are still significant amounts of snow and ice in the region’s smaller watercourses, there is the potential for blockages that will cause further drainage problems and flooding. In urban areas, blocked catch basins or other drainage inlets could lead to standing water and localized flooding.
The predicted warm weather and rainfall is not expected to cause water levels on the Thames River to raise enough to cause flooding of the river flats. However, there is still up to 20 cm of ice in some places on the river and ice conditions should be expected to degrade and may become unsafe.
People should take extra caution around the river, ditches, and streams. The combination of slippery banks, unstable ice and fast moving cold water can be dangerous. Standing water can also present its own unseen hazards. Children and pets should be kept away from the water.
Some long range forecasts are predicting the significant rainfall early next week that could lead to more flooding. Officials will continue to monitor the situation and update this advisory as necessary.
This message will be in effect until February 17th, 2018.
Contact: Jason Wintermute (519-354-7310 x 227, [email protected]) or Jason Homewood (519-354-7310 x 225, [email protected]) regarding this message.