693
WWCN11 CWTO 121428
HEAT WARNING
FOR SOUTHERN ONTARIO
UPDATED BY ENVIRONMENT CANADA
AT 10:28 A.M. EDT SATURDAY 12 JULY 2025.
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HEAT WARNING FOR:
CITY OF TORONTO
WINDSOR - ESSEX - CHATHAM-KENT
SARNIA - LAMBTON
ELGIN
LONDON - MIDDLESEX
SIMCOE - DELHI - NORFOLK
DUNNVILLE - CALEDONIA - HALDIMAND
OXFORD - BRANT
NIAGARA
CITY OF HAMILTON
HALTON - PEEL
YORK - DURHAM
KITCHENER - CAMBRIDGE - REGION OF WATERLOO
GUELPH - ERIN - SOUTHERN WELLINGTON COUNTY
BELLEVILLE - QUINTE - NORTHUMBERLAND
NAPANEE - CONSECON
KINGSTON - ODESSA - FRONTENAC ISLANDS
LINDSAY - SOUTHERN KAWARTHA LAKES
PETERBOROUGH CITY - LAKEFIELD - SOUTHERN PETERBOROUGH COUNTY
STIRLING - TWEED - SOUTH FRONTENAC
BROCKVILLE - LEEDS AND GRENVILLE
CITY OF OTTAWA
PRESCOTT AND RUSSELL
CORNWALL - MORRISBURG
SMITHS FALLS - LANARK - SHARBOT LAKE.
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==DISCUSSION==
A PROLONGED PERIOD OF EXTREME HEAT AND HUMIDITY CONTINUES.
WHAT:
DAYTIME HIGHS OF 29 TO 32 DEGREES CELSIUS AND A HUMIDEX OF 35 TO 40.
OVERNIGHT LOWS OF 19 TO 23 DEGREES CELSIUS, PROVIDING LITTLE RELIEF
FROM THE HEAT.
WHEN:
CONTINUING THROUGH THURSDAY.
ADDITIONAL INFORMATION:
SOUTHERN ONTARIO WILL EXPERIENCE HOT AND HUMID CONDITIONS NOW
THROUGH MUCH OF NEXT WEEK. THE HEAT IS EXPECTED TO EASE SOME FOR
SUNDAY AND MONDAY WITH HOTTER AND MORE HUMID CONDITIONS RETURNING ON
TUESDAY. A SHIFT IN THE WEATHER PATTERN LATE NEXT WEEK WILL LIKELY
END THIS MULTI-DAY PERIOD OF HEAT AND HUMIDITY THURSDAY NIGHT.
TAKE ACTION TO PROTECT YOURSELF AND OTHERS - EXTREME HEAT CAN AFFECT
EVERYONE'S HEALTH. DETERMINE IF YOU OR OTHERS AROUND YOU ARE AT
GREATER RISK OF HEAT ILLNESS. CHECK ON OLDER ADULTS, THOSE LIVING
ALONE AND OTHER AT-RISK PEOPLE IN-PERSON OR ON THE PHONE MULTIPLE
TIMES A DAY.
WATCH FOR THE EARLY SIGNS OF HEAT EXHAUSTION IN YOURSELF AND OTHERS.
SIGNS MAY INCLUDE HEADACHE, NAUSEA, DIZZINESS, THIRST, DARK URINE
AND INTENSE FATIGUE. STOP YOUR ACTIVITY AND DRINK WATER.
HEAT STROKE IS A MEDICAL EMERGENCY(EXCLAMATION MARK) CALL 9-1-1 OR
YOUR EMERGENCY HEALTH PROVIDER IF YOU, OR SOMEONE AROUND YOU, IS
SHOWING SIGNS OF HEAT STROKE WHICH CAN INCLUDE RED AND HOT SKIN,
DIZZINESS, NAUSEA, CONFUSION AND CHANGE IN CONSCIOUSNESS. WHILE YOU
WAIT FOR MEDICAL ATTENTION, TRY TO COOL THE PERSON BY MOVING THEM TO
A COOL PLACE, REMOVING EXTRA CLOTHING, APPLYING COLD WATER OR ICE
PACKS AROUND THE BODY.
DRINK WATER OFTEN AND BEFORE YOU FEEL THIRSTY TO REPLACE FLUIDS.
CLOSE BLINDS, OR SHADES AND OPEN WINDOWS IF OUTSIDE IS COOLER THAN
INSIDE.
TURN ON AIR CONDITIONING, USE A FAN, OR MOVE TO A COOLER AREA OF
YOUR LIVING SPACE. IF YOUR LIVING SPACE IS HOT, MOVE TO A COOL
PUBLIC SPACE SUCH AS A COOLING CENTRE, COMMUNITY CENTRE, LIBRARY OR
SHADED PARK.
FOLLOW THE ADVICE OF YOUR REGION'S PUBLIC HEALTH AUTHORITY.
PLAN AND SCHEDULE OUTDOOR ACTIVITIES DURING THE COOLEST PARTS OF THE
DAY.
LIMIT DIRECT EXPOSURE TO THE SUN AND HEAT. WEAR LIGHTWEIGHT,
LIGHT-COLOURED, LOOSE-FITTING CLOTHING AND A WIDE-BRIMMED HAT.
NEVER LEAVE PEOPLE, ESPECIALLY CHILDREN, OR PETS INSIDE A PARKED
VEHICLE. CHECK THE VEHICLE BEFORE LOCKING TO MAKE SURE NO ONE IS
LEFT BEHIND.
FOR MORE INFORMATION:
HTTPS://WWW.CANADA.CA/EN/HEALTH-CANADA/SERVICES/CLIMATE-CHANGE-HEALTH/EXTREME-HEAT/HOW-PROTECT-YOURSELF.HTML
HTTPS://WWW.CANADA.CA/EN/HEALTH-CANADA/SERVICES/CLIMATE-CHANGE-HEALTH/EXTREME-HEAT/WHO-IS-AT-RISK.HTML
PLEASE CONTINUE TO MONITOR ALERTS AND FORECASTS ISSUED BY
ENVIRONMENT CANADA.
TO REPORT SEVERE WEATHER IN ONTARIO, SEND AN EMAIL TO
ONSTORM(AT)EC.GC.CA OR POST REPORTS ON X USING (HASH)ONSTORM.
HTTP://WEATHER.GC.CA
END/OSPC
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