Northwestern Ontario Weather: Frost Advisories Friday Morning, Showers Arrive Saturday
Sunshine and milder afternoon temperatures are expected Friday, but several inland districts begin the day under frost advisories. A band of showers will move across much of Northwestern Ontario Friday night and Saturday before drier weather returns Sunday
THUNDER BAY – WEATHER DESK – Friday, September 18, 2026 – Families, drivers and outdoor workers should prepare for a sharp change between the cold start and the milder afternoon. Temperatures were near freezing early Friday in Red Lake, Sioux Lookout, Ear Falls and Pickle Lake, while most communities will reach 15°C to 20°C later in the day.
Today is expected to be mainly sunny. South or southeast winds near 20 km/h will develop in many areas. Showers will reach the northwest tonight, spread east on Saturday and generally end by Saturday afternoon.
Sunday should be the quieter day, with sunshine or a mixture of sun and cloud across the region.
Weather Alerts: Frost Advisories Early Friday
Environment and Climate Change Canada had yellow frost advisories in effect early Friday for several Northwestern Ontario forecast districts, including:
- Atikokan, Shebandowan and Quetico Park;
- Ear Falls, Perrault Falls and western Lac Seul;
- Ignace and English River;
- Red Lake and Woodland Caribou Park;
- Savant Lake and Sturgeon Lake;
- Sioux Lookout and eastern Lac Seul; and
- Upsala and Raith.
Patchy frost was expected early Friday as temperatures fell close to freezing. Cold-sensitive plants, trees and crops may be damaged. Residents should cover vulnerable plants and allow frost to clear from vehicle windows before driving.
The advisories are tied to the early-morning cold and may be ended after temperatures rise. Check the Environment Canada weather-alert map for the latest status.
Three-Day Forecast: Friday, September 18 to Sunday, September 20
| Community | Friday | Saturday | Sunday |
|---|---|---|---|
| Kenora and Lake of the Woods | Sunny, then a mix of sun and cloud. South wind 20 km/h. High 18°C. Showers begin after midnight; low 12°C. | Showers ending near noon, then mainly cloudy with a 40% chance of showers. High 18°C. | Sunny. High near 18°C. |
| Dryden and Vermilion Bay | Sunny. South wind 20 km/h late this morning. High 18°C. Showers begin after midnight; low °C. | Showers ending near noon, then mainly cloudy with a 40% chance of showers. High 16°C. | Sunny. High near 18C. |
| Sioux Lookout and Savant Lake | Sunny. Southeast wind 20 km/h becoming light. High 16°C. Showers begin after midnight; low 9°C. | Showers ending near noon, then mainly cloudy with a 40% chance of showers. High 16°C. | Sunny. High near 17°C. |
| Red Lake and Ear Falls | Sunny. South or southeast wind 20 km/h. High 17°C. A few showers begin late this evening; low 12°C. | A few showers ending near noon, then clearing. High 18°C. | Sunny. High near 18°C. |
| Fort Frances, Emo and Rainy River | Sunny, then a mix of sun and cloud. Southeast wind 20 km/h. High 20°C. A few clouds tonight; low 6°C. | A mix of sun and cloud with a 60% chance of showers. High 19°C. | Sunny. High near 18°C. |
| Atikokan and Quetico Park | Sunny. Southeast wind 20 km/h. High 17°C. Clear tonight; low 6°C. | Sunny early, then a mix of sun and cloud with a 40% chance of afternoon showers. High 19°C. | A mix of sun and cloud. High near 18°C. |
| Pickle Lake | Sunny. South wind 20 km/h. High 15°C. Showers begin near midnight; low 9°C. | Showers ending in the morning, then mainly cloudy with a 40% chance of showers. High 17°C. | A mix of sun and cloud. High near 15°C. |
| Ignace and English River | Sunny. Southeast wind 20 km/h becoming light late this morning. High 17°C. Becoming partly cloudy tonight; low 9°C. | Mainly cloudy with a 60% chance of showers. High 16°C. | Sunshine returns, with a high in the upper teens. |
Friday: Cold Start, Sunny Afternoon
The greatest short-term concern is frost in exposed and low-lying areas. At 5:00 a.m. CDT, Environment Canada observations showed approximately 1°C at Red Lake, 0°C at Sioux Lookout and 2°C at Ear Falls. Pickle Lake was near 0°C, with a wind chill near -3.
Sunshine will quickly improve conditions. Afternoon highs will range from about 15°C at Pickle Lake to 20°C around Fort Frances, Emo and Rainy River. South or southeast winds near 20 km/h may create a light chop on larger lakes.
Saturday: Showers Cross the Region
Showers will begin late Friday evening or overnight around Red Lake and Ear Falls, then after midnight around Kenora, Dryden, Sioux Lookout, Savant Lake and Pickle Lake.
Much of the morning will be wet across the northwest. The rain should end near noon in Kenora, Dryden, Sioux Lookout, Savant Lake, Red Lake and Ear Falls, although a 40 per cent chance of additional showers remains in several areas.
Fort Frances, Emo and Rainy River have a 60 per cent chance of showers Saturday. Atikokan and Quetico Park may stay dry through the morning before a 40 per cent chance of showers develops in the afternoon.
Sunday: Drier and Brighter
Sunday is expected to bring the best travel and outdoor conditions of the weekend. Kenora, Dryden, Sioux Lookout, Red Lake, Ear Falls, Fort Frances, Emo and Rainy River should be sunny, with highs generally between 17°C and 18°C.
Atikokan and Pickle Lake should see a mixture of sun and cloud. Pickle Lake will remain cooler, with a high near 15°C. Sunday forecasts carry more uncertainty and should be refreshed before publication or travel.
Travel Outlook: Frost, Fog and Wet Roads
Patchy frost and localized fog may briefly reduce visibility or make exposed surfaces slippery early Friday, especially around Sioux Lookout, Red Lake, Ear Falls, Ignace and Atikokan. Drivers should clear every window, use low-beam headlights in fog and leave extra stopping distance.
Roads may become wet Friday night and Saturday along Highways 17, 71, 72, 105, 502 and 599. Fallen leaves can reduce traction when wet. No snow or freezing-rain threat is indicated in the three-day forecast.
Anyone travelling on remote roads should carry a charged phone, warm clothing and basic emergency supplies. Check Ontario 511 before departure for road closures, construction and incidents.
Boating and Outdoor Work
Friday should offer generally manageable conditions on many inland lakes, but south or southeast winds near 20 km/h can make open water choppier than sheltered bays. Conditions may deteriorate as showers move in Friday night and Saturday.
- Wear an approved personal flotation device and dress for cold water, not only the afternoon air temperature.
- Check the latest local forecast before leaving shore.
- Carry reliable communications and tell someone your route and return time.
- Do not assume calm conditions at a dock represent conditions on open water.
- Outdoor workers should use layers Friday morning and keep rain gear ready for Saturday.
School Bus Status
No school bus cancellation or delay notice was displayed on the Northwestern Ontario Student Services Consortium public home page at the morning check.
This does not guarantee that every route will operate on time. Individual route alerts can be posted after the morning check. Families should monitor the consortium website and Parent Portal before students leave home.
No operational or driver-shortage cancellation was publicly listed at the time checked. If a later notice is issued, it should be identified separately from any weather-related cancellation.
