THUNDER BAY – WEATHER – Thunder Bay begins Thursday under widespread wildfire smoke, sharply reduced visibility and very poor air quality. Environment Canada has issued an Orange Air Quality Warning with a high impact level and high forecast confidence. Residents are being urged to limit outdoor exposure and reconsider outdoor sports, events and strenuous activities.
Today’s Weather Overview
Current Conditions
At 4:00 a.m. EDT, Thunder Bay Airport reported a temperature of 16.1°C under smoky skies. Humidity was high at 89 per cent, with a dew point of 14.3°C, giving the early morning a damp and slightly muggy feel.
Winds were from the southwest at 9 km/h. Barometric pressure stood at 102.0 kPa and was rising, while smoke had reduced visibility to only 3 kilometres.
Today’s Forecast
Widespread smoke will remain the main weather concern through Thursday. The afternoon temperature is expected to reach 25°C, with a Humidex of 28. The UV index will be 6, or high, although smoke may make the sunlight appear muted.
Thursday night will be mainly cloudy, with a 40 per cent chance of showers overnight and a risk of a thunderstorm. The overnight low will fall to 15°C.
Air-Quality Warning
Wildfire smoke is producing very poor air quality and reduced visibility across the City of Thunder Bay. Environment Canada warns that everyone can be affected during heavy smoke, regardless of age or health status. Possible symptoms include irritated eyes, nose or throat, headaches and coughing. More serious symptoms can include wheezing, chest pain or a severe cough.
People aged 65 and older, pregnant people, young children, those with chronic medical conditions and people who work outdoors face a greater risk. They should avoid strenuous outdoor activity and seek medical attention if concerning symptoms develop. Anyone experiencing a medical emergency should obtain immediate assistance.
Keep doors and windows closed where practical and use a suitable ventilation filter or certified portable air cleaner. When outdoor exposure cannot be avoided, a properly fitted N95 or equivalent respirator can reduce exposure to fine smoke particles, although it does not remove all risk.
Thunder Bay’s forecast maximum Air Quality Health Index is 10+—Very High Risk—through Thursday, Thursday night and Friday.
Tomorrow’s Forecast
Friday, July 17
Friday will be cloudy with a 60 per cent chance of showers. The daytime high will reach 24°C. Clouds and occasional rainfall may offer some temporary changes in smoke concentration, but residents should continue monitoring air-quality updates.
Friday night will remain cloudy with a 30 per cent chance of showers and a low of 12°C.
Saturday, July 18
Saturday should begin cloudy before conditions gradually clear. The temperature will rise to 26°C, followed by a clear night and a low of 13°C.
Sunday, July 19
Sunday will bring a 30 per cent chance of showers with a high of 26°C. The chance of rain increases to 40 per cent Sunday night, when temperatures will fall to approximately 14°C.
Wardrobe Recommendations
Choose lightweight, breathable clothing for Thursday’s warm and humid conditions. A light long-sleeved shirt may help limit skin exposure to smoke particles and the high UV index.
Carry a compact rain jacket or umbrella for the possibility of overnight showers and Friday’s wetter forecast. Cooler evening temperatures on Friday and Saturday make a light sweater or jacket useful.
Anyone who must be outside during the smoke should consider wearing a properly fitted N95 or equivalent respirator. Outdoor exercise and other strenuous activities should be postponed while the warning remains in effect.
Weather Trivia
Canada’s Air Quality Health Index runs from 1 to 10+. Values from 1 to 3 represent low risk, 4 to 6 moderate risk, 7 to 10 high risk, and anything above 10 is classified as very high risk. At that highest level, at-risk residents are advised to avoid strenuous outdoor activity, while the general population should reduce or reschedule demanding outdoor exercise..
