Hot Days, Tropical Nights as Heatwave Bakes Eastern Lac Seul Region
SIOUX LOOKOUT – WEATHER REPORT – Sioux Lookout and the Eastern Lac Seul region remain under a Heat Warning as Environment Canada keeps the alert in place until at least Wednesday night. This early-season heat event is packing a punch, with highs reaching 30°C and sultry overnight lows of 17°C offering little relief for tired fans and overworked air conditioners. It’s a heatwave that’s making residents question if it’s really still spring—or if summer has crash-landed a month early.
A Hot, Hazy Forecast Through Friday
At 5:00 AM CDT this morning, the thermometer at Sioux Lookout Airport registered 17.5°C under mainly clear skies. Winds are currently light from the southeast at 13 km/h, while humidity sits at a dry 36%, giving the morning air that unmistakable prairie heatwave feel. The barometric pressure is 100.4 kPa and rising—suggesting stable, sunny weather will continue, at least for now.
Today will see sunshine dominate the skies, with south winds ramping up to 30 km/h, gusting to 50 km/h by late morning. The high will climb to a toasty 30°C, with a humidex of 30 making it feel exactly as hot as it sounds. The UV index will be a sizzling 8—very high—so wide-brimmed hats, SPF 50, and staying in the shade are highly recommended.
Tonight will remain clear and warm with a low of 17°C. Winds will ease after sunset but expect the air to stay muggy, offering little overnight cooling.
Wednesday will bring more sun in the morning before turning into a mix of sun and cloud by the afternoon, along with a 40 percent chance of showers and the risk of a thunderstorm—Nature’s attempt at a cool down, perhaps? Temperatures will again climb to 30°C, and the UV index will remain high at 8. Wednesday night will finally cool to 15°C under clearing skies.
Thursday brings a subtle but welcome change, with a mix of sun and cloud and a 30 percent chance of showers during the day. The high will ease to a more seasonable 25°C. Showers will move in overnight with a low of 14°C.
By Friday, it will finally feel like May again, with cloudy skies, a 40 percent chance of showers, and a much cooler high of 18°C. The night will continue cloudy and damp, dipping to just 4°C—yes, you might actually want to find that extra blanket.
How to Stay Cool in Sioux Lookout’s Sudden Summer
While the lakes might be tempting, don’t let them fool you—heat exhaustion can still strike when you least expect it. Stick to lightweight, breathable clothes, keep hydrated, and limit activity to the cooler parts of the day. If the heat becomes too much, head to shaded parks, cooling centres, or enjoy the natural chill of a forest trail—but don’t forget your bug spray.
Historical Highs and Lows for May 13
Sioux Lookout’s record high for today is a steamy 31.0°C, while the record low is a frosty -2.5°C. With today’s high forecast to hit 30°C, we are once again flirting with record-breaking territory.
Sioux Lookout Weather Fun Fact
Did you know? Despite its location near cool lakes and dense forests, Sioux Lookout can experience intense heat events thanks to its inland position and exposure to southern airflows. Locals call it the “Sauna Lookout” effect, and this week is living up to that nickname.
