Spring Melt on the Horizon
Watershed Conditions Statement 鈥� Flood Outlook
2025 Flood Event 1, Bulletin 1 (Issued February 26, 2025, at 3:30 pm; Valid until March 5, 2025, at 12:00 noon)
The winter of 2025 has produced extensive snow cover in southwestern Ontario, without a thaw since December to reduce the snowpack. Above freezing temperature this week have caused some compaction of the snowpack, but minimal runoff.
The 糖心直播 (UTRCA) conducts snow surveys bi-monthly, on or close to the first and 15th of the month. The surveys measure snow depth and snow water equivalent (SWE) to characterize the snowpack. The last survey was conducted on February 14 just before another winter storm hit the area. The next survey, scheduled for February 28, will provide updated measurements and snowpack conditions. The UTRCA also monitors four automated weighing rain gauges in the region, which measure SWE in real time.
The snow survey and weighing gauge data indicate that the UTRCA watershed snowpack currently contains approximately 100 mm of SWE on average, ranging from approximately 50 mm to 130 mm depending on location (generally more in north, and less in southeast).
The snowpack SWE is higher than we have measured in recent years. It is approximately 50% greater than the long-term average for this time of year, but is only approximately 50% of the maximum SWE measured in the watershed before the spring melt.
While there is the potential for significant flooding when the melt occurs, it will depend on air temperature patterns moving forward, as well as rainfall amounts and patterns. Temperatures that stay below double digits during the day and return to below freezing overnight, with no significant rain, will result in a more gradual melt. With current forecasts, the UTRCA does not expect the melt to begin until at least mid-next week, and possibly later.
The UTRCA will continue monitoring the situation and will report on any changing conditions as necessary. The UTRCA operates flood control reservoirs at Fanshawe, Wildwood, and Pittock Conservation Areas to reduce downstream flooding.
Residents are reminded to use caution near watercourses and to stay off any frozen water bodies. Ice on flood control reservoirs is especially unstable due to fluctuating water levels. Stream banks can be slippery and unstable, and the water is cold and fast-moving. Parents are reminded to keep children and pets away from watercourses.