Residents across parts of Durham Region are being warned to prepare for significant rainfall Monday as another round of showers and thunderstorms moves through the area.
Environment Canada has issued a special weather statement warning that Durham heavy rain could produce total rainfall amounts of 30 to 50 millimetres, while some locations could receive more than 50 millimetres.
The heavier rain is expected through Monday afternoon and evening.
Up to 25 mm already fell Monday morning
The special weather statement represents a significant change from the lighter showers forecast earlier Monday morning.
Environment Canada said some areas had already received up to 25 millimetres of rain during the morning.
Another round of showers and embedded thunderstorms is expected during the afternoon and evening.
Areas affected by thunderstorms could receive an additional 20 to 30 millimetres locally.
Because thunderstorms can produce highly localized downpours, rainfall totals may vary considerably between different Durham communities.
Some neighbourhoods could therefore receive substantially more rain than nearby areas.
Local rainfall totals could exceed 50 mm
Environment Canada is forecasting total rainfall amounts generally between 30 and 50 millimetres.
Local amounts could exceed 50 millimetres where heavier thunderstorms repeatedly move across the same area.
The federal weather agency said rainfall warnings may become necessary depending on how conditions develop.
As of Monday afternoon, however, the alert affecting Pickering, Oshawa and southern Durham was classified as a special weather statement rather than a rainfall warning.
Residents should continue monitoring Environment Canada alerts because the status can change quickly during periods of heavy thunderstorms.
Water could pool on Durham roads
The amount of rain expected Monday could create difficult driving conditions.
Environment Canada says water will likely accumulate on roads and in low-lying areas.
Drivers should be particularly cautious where drainage is poor and should avoid driving through water covering a roadway when its depth cannot be determined.
Heavy downpours can also reduce visibility suddenly.
The potential for road pooling comes as motorists are already dealing with scheduled construction and lane restrictions on several Durham-area provincial highways Monday.
Drivers travelling during the afternoon or evening should allow additional time and check current road and weather conditions before leaving.
Conservation authorities monitor local conditions
Conservation authorities serving Durham Region monitor rainfall, creek levels and watershed conditions to assess the potential for flooding.
Residents living near creeks, rivers or other low-lying areas should pay close attention to any flood messages issued as the rain continues.
Conditions around waterways can change quickly following intense rainfall.
People should also keep children and pets away from fast-moving streams, culverts and flooded areas.
Stormy weather continues Monday evening
The latest Durham heavy rain forecast calls for showers and embedded thunderstorms to continue through the afternoon and evening before conditions gradually improve.
The exact amount received in any individual community will depend on where the strongest thunderstorms develop.
Environment Canada expects widespread totals of 30 to 50 millimetres, but localized rainfall could exceed 50 millimetres.
Residents should monitor updated forecasts and alerts throughout Monday and be prepared for changing travel conditions, temporary road pooling and potentially heavier rainfall where thunderstorms occur.
