FPCN11 CWTO 050346 AAA UPDATED FORECASTS FOR SOUTHERN ONTARIO AND THE NATIONAL CAPITAL REGION ISSUED BY ENVIRONMENT CANADA AT 11:45 P.M. EDT MONDAY 4 MAY 2026 FOR TONIGHT TUESDAY AND TUESDAY NIGHT. THE NEXT SCHEDULED FORECAST WILL BE ISSUED AT 5:00 A.M. EDT TUESDAY. RODNEY - SHEDDEN - WESTERN ELGIN COUNTY. TONIGHT..A FEW SHOWERS ENDING BEFORE MORNING THEN MAINLY CLOUDY WITH 40 PERCENT CHANCE OF SHOWERS. RISK OF A THUNDERSTORM LATE THIS EVENING AND OVERNIGHT. LOCAL AMOUNT 5 MM. WIND SOUTHWEST 20 KM/H GUSTING TO 40 BECOMING LIGHT AFTER MIDNIGHT. WIND BECOMING SOUTHWEST 20 GUSTING TO 40 BEFORE MORNING. LOW 12. TUESDAY..CLOUDY. 40 PERCENT CHANCE OF SHOWERS IN THE MORNING. SHOWERS BEGINNING NEAR NOON. AMOUNT 5 MM. WIND SOUTHWEST 20 KM/H GUSTING TO 50 BECOMING NORTHWEST 20 LATE IN THE MORNING THEN LIGHT IN THE AFTERNOON. HIGH 15. UV INDEX 4 OR MODERATE. TUESDAY NIGHT..PERIODS OF RAIN. AMOUNT 5 TO 10 MM. LOW 6. ST. THOMAS - AYLMER - EASTERN ELGIN COUNTY. TONIGHT..A FEW SHOWERS ENDING BEFORE MORNING THEN MAINLY CLOUDY WITH 40 PERCENT CHANCE OF SHOWERS. RISK OF A THUNDERSTORM LATE THIS EVENING AND OVERNIGHT. LOCAL AMOUNT 5 MM. WIND SOUTHWEST 20 KM/H GUSTING TO 40. LOW 13. TUESDAY..CLOUDY. 40 PERCENT CHANCE OF SHOWERS IN THE MORNING. SHOWERS BEGINNING NEAR NOON. AMOUNT 5 MM. WIND SOUTHWEST 20 KM/H BECOMING NORTHWEST 20 GUSTING TO 40 IN THE MORNING. HIGH 15. UV INDEX 4 OR MODERATE. TUESDAY NIGHT..PERIODS OF RAIN. AMOUNT 5 TO 10 MM. LOW 6. SIMCOE - DELHI - NORFOLK. TONIGHT..A FEW SHOWERS ENDING BEFORE MORNING THEN MAINLY CLOUDY WITH 40 PERCENT CHANCE OF SHOWERS. RISK OF A THUNDERSTORM LATE THIS EVENING AND OVERNIGHT. LOCAL AMOUNT 5 MM. WIND SOUTHWEST 30 KM/H GUSTING TO 60. LOW 12. TUESDAY..CLOUDY. 40 PERCENT CHANCE OF SHOWERS IN THE MORNING. SHOWERS BEGINNING NEAR NOON. AMOUNT 5 MM. WIND SOUTHWEST 30 KM/H GUSTING TO 50 BECOMING NORTHWEST 20 IN THE AFTERNOON. HIGH 15. UV INDEX 4 OR MODERATE. TUESDAY NIGHT..PERIODS OF RAIN. AMOUNT 5 TO 10 MM. WIND BECOMING NORTHEAST 20 KM/H BEFORE MORNING. LOW 7. DUNNVILLE - CALEDONIA - HALDIMAND. TONIGHT..SHOWERS WITH RISK OF A THUNDERSTORM. WIND SOUTHWEST 30 KM/H GUSTING TO 50. LOW 12. TUESDAY..SHOWERS. AMOUNT 5 MM. WIND SOUTHWEST 30 KM/H GUSTING TO 60 BECOMING NORTHWEST 20 IN THE AFTERNOON. HIGH 16. UV INDEX 4 OR MODERATE. TUESDAY NIGHT..RAIN. AMOUNT 10 TO 15 MM. WIND BECOMING NORTHEAST 20 KM/H AFTER MIDNIGHT. LOW 7. NIAGARA FALLS - WELLAND - SOUTHERN NIAGARA REGION. TONIGHT..SHOWERS WITH RISK OF A THUNDERSTORM. WIND SOUTHWEST 20 KM/H GUSTING TO 40 INCREASING TO 40 GUSTING TO 70 AFTER MIDNIGHT. LOW 12. TUESDAY..SHOWERS. AMOUNT 5 MM. WIND SOUTHWEST 30 KM/H GUSTING TO 60. HIGH 16. UV INDEX 4 OR MODERATE. TUESDAY NIGHT..RAIN. AMOUNT 10 TO 15 MM. WIND BECOMING NORTHEAST 20 KM/H AFTER MIDNIGHT. LOW PLUS 5. ST. CATHARINES - GRIMSBY - NORTHERN NIAGARA REGION. TONIGHT..SHOWERS WITH RISK OF A THUNDERSTORM. WIND SOUTHWEST 20 KM/H GUSTING TO 40 INCREASING TO 40 GUSTING TO 70 AFTER MIDNIGHT. LOW 12. TUESDAY..SHOWERS. AMOUNT 5 MM. WIND SOUTHWEST 30 KM/H GUSTING TO 60. HIGH 16. UV INDEX 4 OR MODERATE. TUESDAY NIGHT..RAIN. AMOUNT 10 TO 15 MM. WIND BECOMING NORTHEAST 20 KM/H BEFORE MORNING. LOW 6. REMAINDER UNCHANGED. END