A Quieter Start After a Stormy Night, But Haze and Humidex to Rise

Thunder Bay – Weather – After a night of thunder and lightning, Thunder Bay wakes up to calm, muggy, and mostly cloudy conditions this morning.

The air is thick with humidity, and haze will settle in under mostly sunny skies later today. While the storms have passed, conditions remain hot and hazy, with humidex values pushing to 35°C — making this another day to stay hydrated and sun-protected.

Current Conditions (as of 7:00 AM EDT at Thunder Bay Airport)

• Temperature: 18.8°C

• Dew Point: 16.7°C

• Humidity: 88%

• Wind: West-northwest at 20 km/h, gusting to 33 km/h

• Pressure: 101.5 kPa (rising)

• Visibility: 32 km

• Condition: Mostly cloudy with high humidity and light breeze

Today’s Forecast – Monday, July 28

• Sky: Mainly sunny with hazy conditions developing by mid-morning

• Wind: Northwest at 20 km/h, gusting to 40 km/h

• High Temperature: 28°C

• Humidex: 35 – Feels significantly hotter

• UV Index: 8 – Very High

⚠️ Haze may reduce visibility and affect air quality for sensitive individuals. Limit outdoor activity if you experience irritation.

Tonight

• Conditions: Partly cloudy with a 30% chance of showers this evening and after midnight

• Clearing before morning

• Haze continues into the overnight hours

• Wind: Northwest 20 km/h, becoming light overnight

• Low: 16°C

Extended Forecast

Tuesday, July 29:

• Conditions: Sunny, becoming a mix of sun and cloud by mid-morning

• Hazy skies remain

• Wind: Northwest 20 km/h by late morning

• High: 25°C

• Humidex: 30

• UV Index: 8 – Very High

• Night: Clear, low of 10°C

Wednesday, July 30:

• Conditions: Sunny all day

• High: 24°C

• Night: Clear, low of 9°C

Wardrobe & Safety Tips

• Today: Lightweight, loose-fitting clothing is essential for managing heat and humidity. Wear a hat, sunglasses, and SPF 30+ sunscreen. If sensitive to smoke or haze, limit outdoor activity or use a mask.

• Tonight: Bring light rain gear if out late, as brief showers may move in before skies clear.

• Tuesday-Wednesday: Transition to more comfortable, slightly cooler weather. A light jacket may be needed overnight as lows drop into the single digits by midweek.

Weather Trivia

Did You Know?
Thunder Bay often experiences post-storm haze following humid summer thunderstorms. After lightning-filled nights like last night, rising heat and residual moisture trap particulates and moisture in the air, leading to morning humidity and afternoon haze — especially when winds shift from the northwest.