FPCN11 CWTO 181218 AAA
UPDATED FORECASTS FOR SOUTHERN ONTARIO AND THE NATIONAL CAPITAL
REGION ISSUED BY ENVIRONMENT CANADA AT 8:17 A.M. EDT MONDAY 18 MAY
2026 FOR TODAY AND TUESDAY.
THE NEXT SCHEDULED FORECAST WILL BE ISSUED AT 11:00 A.M. EDT.

PRESCOTT AND RUSSELL.
TODAY..A FEW SHOWERS ENDING LATE THIS MORNING THEN A MIX OF SUN AND
 CLOUD WITH 30 PERCENT CHANCE OF SHOWERS. RISK OF A THUNDERSTORM THIS
 MORNING. WIND BECOMING SOUTH 20 KM/H GUSTING TO 40 THIS AFTERNOON.
 HIGH 28. HUMIDEX 33. UV INDEX 9 OR VERY HIGH.
TONIGHT..CLEAR. INCREASING CLOUDINESS OVERNIGHT THEN 40 PERCENT
 CHANCE OF SHOWERS BEFORE MORNING. WIND SOUTHWEST 20 KM/H BECOMING
 LIGHT THIS EVENING. LOW 19.
TUESDAY..A MIX OF SUN AND CLOUD WITH 40 PERCENT CHANCE OF SHOWERS.
 WIND BECOMING WEST 30 KM/H IN THE MORNING. HIGH 29. HUMIDEX 34. UV
 INDEX 9 OR VERY HIGH.

MORRISBURG - LONG SAULT.
TODAY..A FEW SHOWERS ENDING LATE THIS MORNING THEN A MIX OF SUN AND
 CLOUD WITH 30 PERCENT CHANCE OF SHOWERS. RISK OF A THUNDERSTORM THIS
 MORNING. WIND BECOMING SOUTHWEST 20 KM/H GUSTING TO 40 THIS
 AFTERNOON. HIGH 29. HUMIDEX 34. UV INDEX 9 OR VERY HIGH.
TONIGHT..CLEAR EARLY THIS EVENING THEN PARTLY CLOUDY WITH 40 PERCENT
 CHANCE OF SHOWERS BEFORE MORNING. WIND SOUTHWEST 20 KM/H. LOW 20.
TUESDAY..A MIX OF SUN AND CLOUD WITH 40 PERCENT CHANCE OF SHOWERS.
 WIND BECOMING SOUTHWEST 30 KM/H IN THE MORNING. HIGH 31. HUMIDEX 36.
 UV INDEX 8 OR VERY HIGH.

CORNWALL - LANCASTER.
TODAY..A FEW SHOWERS ENDING LATE THIS MORNING THEN A MIX OF SUN AND
 CLOUD WITH 30 PERCENT CHANCE OF SHOWERS. RISK OF A THUNDERSTORM THIS
 MORNING. WIND NORTHEAST 20 KM/H BECOMING LIGHT LATE THIS MORNING.
 HIGH 29. HUMIDEX 34. UV INDEX 9 OR VERY HIGH.
TONIGHT..CLEAR EARLY THIS EVENING THEN PARTLY CLOUDY WITH 40 PERCENT
 CHANCE OF SHOWERS BEFORE MORNING. LOW 19.
TUESDAY..A MIX OF SUN AND CLOUD WITH 40 PERCENT CHANCE OF SHOWERS.
 WIND BECOMING SOUTHWEST 30 KM/H IN THE MORNING. HIGH 29. HUMIDEX 34.
 UV INDEX 8 OR VERY HIGH.

WINCHESTER - NEWINGTON.
TODAY..A FEW SHOWERS ENDING LATE THIS MORNING THEN A MIX OF SUN AND
 CLOUD WITH 30 PERCENT CHANCE OF SHOWERS. RISK OF A THUNDERSTORM THIS
 MORNING. WIND BECOMING SOUTHWEST 20 KM/H GUSTING TO 40 THIS
 AFTERNOON. HIGH 29. HUMIDEX 34. UV INDEX 9 OR VERY HIGH.
TONIGHT..CLEAR. INCREASING CLOUDINESS OVERNIGHT THEN 40 PERCENT
 CHANCE OF SHOWERS BEFORE MORNING. WIND SOUTHWEST 20 KM/H GUSTING TO
 40 BECOMING LIGHT THIS EVENING. LOW 19.
TUESDAY..A MIX OF SUN AND CLOUD WITH 40 PERCENT CHANCE OF SHOWERS.
 WIND BECOMING SOUTHWEST 30 KM/H IN THE MORNING. HIGH 29. HUMIDEX 33.
 UV INDEX 8 OR VERY HIGH.

MAXVILLE - ALEXANDRIA.
TODAY..A FEW SHOWERS ENDING LATE THIS MORNING THEN A MIX OF SUN AND
 CLOUD WITH 30 PERCENT CHANCE OF SHOWERS. RISK OF A THUNDERSTORM THIS
 MORNING. WIND NORTHEAST 20 KM/H BECOMING SOUTH 20 EARLY THIS
 AFTERNOON. HIGH 28. HUMIDEX 33. UV INDEX 9 OR VERY HIGH.
TONIGHT..CLEAR THIS EVENING AND AFTER MIDNIGHT THEN PARTLY CLOUDY
 WITH 40 PERCENT CHANCE OF SHOWERS BEFORE MORNING. WIND SOUTHWEST
 20 KM/H BECOMING LIGHT THIS EVENING. WIND BECOMING SOUTH 20 GUSTING
 TO 40 BEFORE MORNING. LOW 19.
TUESDAY..A MIX OF SUN AND CLOUD WITH 40 PERCENT CHANCE OF SHOWERS.
 WIND BECOMING SOUTHWEST 30 KM/H IN THE MORNING. HIGH 29. HUMIDEX 34.
 UV INDEX 8 OR VERY HIGH.

REMAINDER UNCHANGED.

END