FPCN11 CWTO 181305 AAA UPDATED FORECASTS FOR SOUTHERN ONTARIO AND THE NATIONAL CAPITAL REGION ISSUED BY ENVIRONMENT CANADA AT 9:04 A.M. EDT SATURDAY 18 JULY 2026 FOR TODAY AND SUNDAY. THE NEXT SCHEDULED FORECAST WILL BE ISSUED AT 11:00 A.M. EDT. CALEDON. TODAY..A FEW SHOWERS BECOMING MIXED WITH THUNDERSTORMS EARLY THIS AFTERNOON AND ENDING LATE THIS AFTERNOON THEN CLOUDY WITH 30 PERCENT CHANCE OF SHOWERS. RISK OF A THUNDERSTORM LATE THIS MORNING. LOCAL AMOUNT 20 TO 30 MM. LOCAL SMOKE. WIND SOUTHWEST 20 KM/H GUSTING TO 40 BECOMING NORTHWEST 30 GUSTING TO 50 NEAR NOON. HIGH 26. HUMIDEX 34. UV INDEX 4 OR MODERATE. TONIGHT..MAINLY CLOUDY. 30 PERCENT CHANCE OF SHOWERS THIS EVENING. LOCAL SMOKE. WIND NORTHWEST 30 KM/H GUSTING TO 50. LOW 15. SUNDAY..CLEARING. LOCAL SMOKE EARLY IN THE MORNING. WIND NORTH 20 KM/H BECOMING LIGHT IN THE AFTERNOON. HIGH 22. UV INDEX 8 OR VERY HIGH. VAUGHAN - RICHMOND HILL - MARKHAM. TODAY..SHOWERS OR THUNDERSTORMS. LOCAL AMOUNT 20 TO 30 MM. LOCAL SMOKE. WIND SOUTHWEST 20 KM/H GUSTING TO 40 BECOMING NORTHWEST 30 GUSTING TO 50 THIS AFTERNOON. HIGH 26. HUMIDEX 34. UV INDEX 4 OR MODERATE. TONIGHT..MAINLY CLOUDY. 30 PERCENT CHANCE OF SHOWERS THIS EVENING. LOCAL SMOKE. WIND NORTHWEST 30 KM/H GUSTING TO 50. LOW 15. SUNDAY..CLEARING. WIND NORTH 20 KM/H BECOMING LIGHT IN THE AFTERNOON. HIGH 23. HUMIDEX 25. UV INDEX 8 OR VERY HIGH. NEWMARKET - GEORGINA - NORTHERN YORK REGION. TODAY..A FEW SHOWERS BECOMING MIXED WITH THUNDERSTORMS EARLY THIS AFTERNOON AND ENDING LATE THIS AFTERNOON THEN CLOUDY WITH 30 PERCENT CHANCE OF SHOWERS. RISK OF A THUNDERSTORM LATE THIS MORNING. LOCAL AMOUNT 20 TO 30 MM. LOCAL SMOKE. WIND SOUTHWEST 20 KM/H GUSTING TO 40 BECOMING NORTHWEST 30 GUSTING TO 50 NEAR NOON. HIGH 25. HUMIDEX 35. UV INDEX 3 OR MODERATE. TONIGHT..MAINLY CLOUDY. 30 PERCENT CHANCE OF SHOWERS THIS EVENING. LOCAL SMOKE. WIND NORTHWEST 30 KM/H GUSTING TO 50. LOW 15. SUNDAY..CLEARING. LOCAL SMOKE EARLY IN THE MORNING. WIND NORTH 20 KM/H BECOMING LIGHT IN THE AFTERNOON. HIGH 22. UV INDEX 8 OR VERY HIGH. ORANGEVILLE - GRAND VALLEY - SOUTHERN DUFFERIN COUNTY. TODAY..A FEW SHOWERS BECOMING MIXED WITH THUNDERSTORMS EARLY THIS AFTERNOON AND ENDING LATE THIS AFTERNOON THEN CLOUDY WITH 30 PERCENT CHANCE OF SHOWERS. RISK OF A THUNDERSTORM LATE THIS MORNING. LOCAL AMOUNT 20 TO 30 MM. LOCAL SMOKE. WIND SOUTHWEST 20 KM/H GUSTING TO 40 BECOMING NORTHWEST 30 GUSTING TO 50 NEAR NOON. HIGH 24. HUMIDEX 31. UV INDEX 4 OR MODERATE. TONIGHT..MAINLY CLOUDY. 30 PERCENT CHANCE OF SHOWERS THIS EVENING. LOCAL SMOKE. WIND NORTHWEST 30 KM/H GUSTING TO 50. LOW 14. SUNDAY..CLEARING. LOCAL SMOKE EARLY IN THE MORNING. WIND NORTH 20 KM/H BECOMING LIGHT IN THE AFTERNOON. HIGH 21. UV INDEX 8 OR VERY HIGH. SHELBURNE - MANSFIELD - NORTHERN DUFFERIN COUNTY. TODAY..A FEW SHOWERS BECOMING MIXED WITH THUNDERSTORMS EARLY THIS AFTERNOON AND ENDING LATE THIS AFTERNOON THEN CLOUDY WITH 30 PERCENT CHANCE OF SHOWERS. RISK OF A THUNDERSTORM LATE THIS MORNING. LOCAL AMOUNT 20 TO 30 MM. LOCAL SMOKE. WIND SOUTHWEST 20 KM/H GUSTING TO 40 BECOMING NORTHWEST 30 GUSTING TO 50 NEAR NOON. HIGH 23. HUMIDEX 31. UV INDEX 3 OR MODERATE. TONIGHT..CLOUDY. 30 PERCENT CHANCE OF SHOWERS THIS EVENING. LOCAL SMOKE. WIND NORTHWEST 30 KM/H GUSTING TO 50. LOW 14. SUNDAY..CLEARING. LOCAL SMOKE EARLY IN THE MORNING. WIND NORTH 20 KM/H BECOMING LIGHT IN THE AFTERNOON. HIGH 21. UV INDEX 8 OR VERY HIGH. INNISFIL - NEW TECUMSETH - ANGUS. TODAY..A FEW SHOWERS BECOMING MIXED WITH THUNDERSTORMS EARLY THIS AFTERNOON AND ENDING LATE THIS AFTERNOON THEN CLOUDY WITH 30 PERCENT CHANCE OF SHOWERS. RISK OF A THUNDERSTORM LATE THIS MORNING. LOCAL AMOUNT 20 TO 30 MM. LOCAL SMOKE. WIND SOUTHWEST 20 KM/H GUSTING TO 40 BECOMING NORTHWEST 30 GUSTING TO 50 NEAR NOON. HIGH 24. HUMIDEX 32. UV INDEX 3 OR MODERATE. TONIGHT..MAINLY CLOUDY. 30 PERCENT CHANCE OF SHOWERS THIS EVENING. LOCAL SMOKE. WIND NORTHWEST 30 KM/H GUSTING TO 50. LOW 14. SUNDAY..CLEARING IN THE MORNING. LOCAL SMOKE EARLY IN THE MORNING. WIND NORTH 20 KM/H BECOMING LIGHT IN THE AFTERNOON. HIGH 21. UV INDEX 8 OR VERY HIGH. REMAINDER UNCHANGED. END