Durham Region residents should keep an umbrella handy today as Environment Canada forecasts a risk of thunderstorms throughout Tuesday, with up to 25 millimetres of rain possible across parts of southern Ontario.
The morning is expected to start off sunny before increased cloud cover rolls in by midday, bringing a 40 per cent chance of showers during the afternoon hours. A risk of thunderstorms develops through the late afternoon and early evening across Oshawa, Whitby, Ajax, Pickering, Clarington, and surrounding Durham communities.
Temperatures could reach a high of 26 C inland, though areas closer to Lake Ontario may feel cooler at around 18 to 20 C due to the lake breeze effect. The humidex across Durham is expected to make it feel closer to 29 C in some spots further from the waterfront.
Tuesday night will remain mainly cloudy with another 40 per cent chance of showers and a continued risk of thunderstorms overnight. Between 10 and 20 millimetres of rainfall is expected across most of Durham, with up to 25 millimetres possible in localized areas if thunderstorms develop. The overnight low will sit around 19 C.
Looking ahead to Wednesday and the rest of the week, conditions are expected to remain cloudy with a 30 per cent chance of showers throughout the day. The high should reach 29 C with a low of 21 C, continuing the warm, humid, and unsettled pattern southern Ontario has experienced through the first week of June.
Durham Region has already seen its share of active weather this month, with thunderstorm watches and heat alerts issued during the first week of June. The oscillating temperatures and storm systems have kept residents on their toes as summer weather patterns begin taking shape across the Greater Toronto Area.
Environment Canada advises residents to monitor weather alerts throughout the day as conditions may change rapidly if storms develop. Thunderstorms in southern Ontario during June can produce heavy downpours, gusty winds, small hail, and frequent lightning, particularly in the afternoon and evening hours when atmospheric instability peaks.
The thunderstorm risk serves as a timely reminder to secure loose outdoor furniture, ensure sump pumps are functioning properly, and avoid unnecessary travel during any active weather warnings. Those with outdoor plans for Tuesday evening should certainly have an indoor backup ready.
Pedestrians and commuters in downtown Oshawa, Whitby, and Pickering should also be cautious of ponding on roads if heavy rain moves through the area during the afternoon rush hour. Visibility may drop significantly during any intense downpour, making driving conditions hazardous.
Pet owners are strongly reminded to bring all animals indoors if thunderstorms are imminent, as loud thunder and lightning can cause distress. Keeping phones charged is also advisable in case of any brief power interruptions associated with local storm activity.
Local parks and outdoor recreation areas may see temporary closures if severe weather warnings are issued. Residents planning to visit waterfront trails along Lake Ontario in Pickering and Ajax should check local advisories before heading out.
Stay tuned to AllAboutDurham for updates throughout the day if any severe weather warnings are issued for Durham Region communities.





















