Mild temperatures, rain and wind are in the forecast for the weekend. As a result, Maitland Conservation is issuing both a Shoreline Conditions Statement – Water Safety and a Watershed Conditions Statement – Water Safety.
Shoreline Conditions Statement – Water Safety
Strong winds expected to cause flooding and erosion problems
A low-pressure system tracking across the Great Lakes is forecasted to bring another strong wind event to the Lake Huron shoreline tomorrow. Winds will strengthen out of the southwest tomorrow morning (Saturday, December 11, 2021), with sustained wind speeds building to 50 kilometres (km) per hour, before shifting more westerly during the afternoon and increasing to 60 km/hr. Peak gusts with this event are expected to reach 90 km/hr. Winds will decrease steadily overnight Saturday and into Sunday morning but will remain strong well into Sunday. This high wind event will begin to generate large waves along the Lake Huron shoreline tomorrow afternoon and, at its peak tomorrow evening, will be capable of producing waves in the range of 3-4 metres. Wave action will decrease slightly overnight and into Sunday but is expected to remain strong through most of the day Sunday.
Residents and municipal officials are reminded to stay well back from breaking waves. In addition, people should stay away from top-of-bluff areas during and after the storm in case there has been any movement of the lake bank. It is important to remember that there may be a delay between erosion at the toe (bottom) of the bluff and subsequent bluff failure.
This message will remain in effect until 10:00 a.m. on Monday December 13, 2021, unless local conditions warrant further updates. Maitland Conservation will continue to monitor conditions and will provide an update if required.
Watershed Conditions Statement – Water Safety
Mild temperatures and rain expected to create bankfull conditions
Approximately 20-30mm of rain is forecasted, beginning tonight and persisting through the day tomorrow until changing to snow Saturday night. Temperatures are expected to climb overnight, reaching a high of 15°C tomorrow. The rainfall and warm temperatures will result in snowmelt and generate a quick runoff throughout the watershed.
Soils in the watershed are saturated from snowmelt and rainfall events over the past month. In response to tomorrow’s rainfall and melting snow, river levels are expected to reach or slightly exceed bankfull conditions with flooding limited to traditional flood prone areas. Rivers are likely to rise quickly over the weekend and remain at high levels through the beginning of next week. Municipal staff should monitor local problem areas and be prepared for the closures of low-lying roads.
Residents are reminded to stay away from rivers, ditches, and streams. Flows will be very fast and very cold over the next several days.
Maitland Conservation staff will continue to carefully monitor conditions and an update on watershed conditions will be provided if warranted. This message will remain in effect until 10:00 a.m. on Tuesday December 14, 2021.
Jeff Winzenried, Flood Forecasting Supervisor
Jayne Thompson, Communications Coordinator
519-335-3557 ext. 226 Cell: 519-357-6670
Types of Flood Messages:
Watershed Conditions Statement – Water Safety – General watershed conditions are being assessed for high runoff potential that could lead to flooding, and to remind the public of general river safety issues.
Watershed Conditions Statement – Flood Outlook – Early notice of the potential for flooding based on weather forecasts calling for heavy rain, snow melt, high wind or other conditions that could lead to high runoff, cause ice jams, lakeshore flooding or erosion.
Flood Watch – Flooding is possible in specific watercourses or municipalities. Municipalities, emergency services and individual landowners in flood-prone areas should prepare.
Flood Warning – Flooding is imminent or already occurring in specific watercourses or municipalities. Municipalities and individuals should take action to deal with flood conditions. This may include road closures and evacuations.