Overview of Latest Warning - Heat: Weather Alerts

Multiple active bulletins issued for this subscription.
Latest bulletin issued on Friday July 3, 2026 16:10 CDT by Environment Canada.

Orange level warning - heat - continued for:
Yellow level warning - heat - continued for:
Other active alerts you subscribe to:

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Alert Details

Issued on Friday July 3, 2026 16:10 CDT
View the alert details of this bulletin only.
Yellow level warning - heat - continued for:
  • Gatineau, Que. (031100)

Impact Level: Moderate
Forecast Confidence: High

A prolonged heat event continues.

What:
Maximum temperatures near 31 degrees Celsius.
Minimum temperatures near 20 degrees Celsius.

When:
This evening. Possibly continuing through Saturday.

Additional Information:
Hot and humid air can also bring deteriorating air quality and can result in the Air Quality Health Index approaching the high-risk category.

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! 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.

Heat warnings are issued when very high temperature or humidity conditions are expected to pose an elevated risk of heat illnesses, such as heat stroke or heat exhaustion.

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, send an email to ONstorm@ec.gc.ca or post reports on X using #QCStorm.

Issued on Friday July 3, 2026 16:03 CDT
View the alert details of this bulletin only.
Orange level warning - heat - continued for:
  • Brockville - Prescott, Ont. (043630)
  • Lindsay - Southern Kawartha Lakes, Ont. (044730)
  • Peterborough City - Lakefield - Southern Peterborough County, Ont. (044740)
  • Prescott and Russell, Ont. (045100)
  • Renfrew - Arnprior - Calabogie, Ont. (045230)
  • City of Ottawa, Ont. (045400)

Impact Level: High
Forecast Confidence: High

A long duration heat event continues.

What:
Maximum temperatures near 32 degrees Celsius
Minimum temperatures near 21 degrees Celsius

When:
Ending tonight. Possibly continuing for some regions through Saturday.

Additional Information:
Hot and humid air can also bring deteriorating air quality and can result in the Air Quality Health Index approaching the high-risk category.

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! 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.

Heat warnings are issued when very high temperature or humidity conditions are expected to pose an elevated risk of heat illnesses, such as heat stroke or heat exhaustion.

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, send an email to ONstorm@ec.gc.ca or post reports on X using #ONStorm.

Issued on Friday July 3, 2026 16:01 CDT
View the alert details of this bulletin only.
Yellow level warning - heat - continued for:
  • Orillia - Lagoon City - Washago, Ont. (044120)
  • Huntsville - Baysville, Ont. (044410)
  • Bracebridge - Gravenhurst, Ont. (044440)
  • Haliburton - Minden - Southern Haliburton County, Ont. (044520)
  • Fenelon Falls - Balsam Lake Park - Northern Kawartha Lakes, Ont. (044710)
  • Apsley - Woodview - Northern Peterborough County, Ont. (044720)
  • Hanover - Dundalk - Southern Grey County, Ont. (046240)
  • Mount Forest - Arthur - Northern Wellington County, Ont. (046410)
  • Shelburne - Mansfield - Northern Dufferin County, Ont. (046520)
  • Orangeville - Grand Valley - Southern Dufferin County, Ont. (046530)

Impact Level: Moderate
Forecast Confidence: Very high

A multi-day heat event continues.

What:
Maximum temperatures near 31 degrees Celsius.
Minimum temperatures near 20 degrees Celsius.

When:
Ending tonight.

Additional Information:
Hot and humid air can also bring deteriorating air quality and can result in the Air Quality Health Index approaching the high-risk category.

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! 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.

Heat warnings are issued when very high temperature or humidity conditions are expected to pose an elevated risk of heat illnesses, such as heat stroke or heat exhaustion.

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, send an email to ONstorm@ec.gc.ca or post reports on X using #ONStorm.

Issued on Friday July 3, 2026 15:55 CDT
View the alert details of this bulletin only.
Orange level warning - heat - continued for:
  • Uxbridge - Beaverton - Northern Durham Region, Ont. (043210)
  • Newmarket - Georgina - Northern York Region, Ont. (043220)
  • Listowel - Milverton - Northern Perth County, Ont. (046320)
  • Stratford - Mitchell - Southern Perth County, Ont. (046340)
  • Guelph - Erin - Southern Wellington County, Ont. (046420)
  • Kitchener - Cambridge - Region of Waterloo, Ont. (046430)
  • Innisfil - New Tecumseth - Angus, Ont. (046510)
  • Caledon, Ont. (046610)

Impact Level: High
Forecast Confidence: High

A long duration heat event continues.

What:
Maximum temperatures near 31 degrees Celsius.
Minimum temperatures near 20 degrees Celsius.

When:
Ending tonight. Possibly continuing for some regions through Saturday.

Additional Information:
Hot and humid air can also bring deteriorating air quality and can result in the Air Quality Health Index approaching the high-risk category.

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! 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.

Heat warnings are issued when very high temperature or humidity conditions are expected to pose an elevated risk of heat illnesses, such as heat stroke or heat exhaustion.

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, send an email to ONstorm@ec.gc.ca or post reports on X using #ONStorm.

Issued on Friday July 3, 2026 15:49 CDT
View the alert details of this bulletin only.
Orange level warning - heat - continued for:
  • Simcoe - Delhi - Norfolk, Ont. (041100)
  • Dunnville - Caledonia - Haldimand, Ont. (041200)
  • London - Parkhill - Eastern Middlesex County, Ont. (041510)
  • St. Thomas - Aylmer - Eastern Elgin County, Ont. (041610)
  • Oxford - Brant, Ont. (041700)
  • City of Toronto, Ont. (043100)
  • Pickering - Oshawa - Southern Durham Region, Ont. (043230)
  • Vaughan - Richmond Hill - Markham, Ont. (043240)
  • Belleville - Quinte - Northumberland, Ont. (043300)
  • City of Hamilton, Ont. (046100)
  • Mississauga - Brampton, Ont. (046620)
  • Halton Hills - Milton, Ont. (046630)
  • Burlington - Oakville, Ont. (046640)
  • Niagara, Ont. (046700)

Impact Level: High
Forecast Confidence: Very high

A long duration heat event continues.

What:
Maximum temperatures of 31 to 33 degrees Celsius.
Minimum temperatures near 21 degrees Celsius.

When:
Continuing through Saturday.

Additional Information:
Hot and humid air can also bring deteriorating air quality and can result in the Air Quality Health Index approaching the high-risk category.

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! 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.

Heat warnings are issued when very high temperature or humidity conditions are expected to pose an elevated risk of heat illnesses, such as heat stroke or heat exhaustion.

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, send an email to ONstorm@ec.gc.ca or post reports on X using #ONStorm.

Issued on Friday July 3, 2026 15:49 CDT
View the alert details of this bulletin only.
Orange level warning - heat - continued for:
  • Windsor - Leamington - Essex County, Ont. (041420)

Impact Level: High
Forecast Confidence: Very high

A long duration heat event continues. For some areas, this is the first heat event of the season.

What:
Maximum temperatures of 32 to 35 degrees Celsius.
Minimum temperatures of 20 to 22 degrees Celsius.

When:
Continuing through Saturday.

Additional Information:
Hot and humid air can also bring deteriorating air quality and can result in the Air Quality Health Index approaching the high-risk category.

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! 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.

Heat warnings are issued when very high temperature or humidity conditions are expected to pose an elevated risk of heat illnesses, such as heat stroke or heat exhaustion.

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, send an email to ONstorm@ec.gc.ca or post reports on X using #ONStorm.

Issued on Friday July 3, 2026 15:46 CDT
View the alert details of this bulletin only.
Yellow level warning - heat - continued for:
  • Sault Ste. Marie - St. Joseph Island, Ont. (048830)
  • North Bay - Powassan - Mattawa, Ont. (049820)

Impact Level: Moderate
Forecast Confidence: High

A multi-day heat event continues.

What:
Maximum temperatures of 28 to 31 degrees Celsius.
Humidex values of 35 to 40.

When:
Ending this evening.

Additional Information:
This is the first heat event of the year for some regions. Hot and humid air can also bring deteriorating air quality and can result in the Air Quality Health Index approaching the high-risk category.

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! 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.

Heat warnings are issued when very high temperature or humidity conditions are expected to pose an elevated risk of heat illnesses, such as heat stroke or heat exhaustion.

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, send an email to ONstorm@ec.gc.ca or post reports on X using #ONStorm.

Latest information is always available here: https://weather.gc.ca/index_e.html?layers=alert
Latest Alert Version: Weather Alerts