Heavy rain and washout risk continue from Armstrong to Nipigon while western Northwestern Ontario begins to clear

Nipigon, Greenstone and Armstrong face the greatest rainfall and washout risk; colder sunshine follows Friday

THUNDER BAY, Ont. – Nov. 4, 2026 – WEATHER – Northwestern Ontario is split Wednesday between improving conditions in the west and heavy rain from Armstrong through Greenstone to Nipigon. Fog, ponding water and north-wind gusts of 40 to 60 km/h are the main travel concerns before colder air brings a rain-snow mix east of Lake Nipigon.

At the 5:28 a.m. EST check, Environment Canada rainfall warnings covered Nipigon and the Geraldton-Longlac-Caramat forecast area used for Greenstone. The warning called for about 50 mm of additional rain and multi-day totals near 80 mm, with higher amounts possible.

A special weather statement for Armstrong forecast 30 to 50 mm from Wednesday into Thursday. Water may pool on roads and washouts are possible near rivers, creeks and culverts.

Wednesday: Western drizzle, eastern downpour

Kenora has a 40 per cent chance of morning drizzle or showers before afternoon breaks, a high of 9 C and north gusts to 40 km/h. Red Lake reaches 8 C and clears in the afternoon. Both areas have a 30 per cent chance of overnight flurries, with lows near 0 C and north gusts of 40 to 50 km/h.

Dryden and Sioux Lookout remain near 7 C with a 40 per cent chance of morning drizzle or showers. North winds gust to 40 km/h by day and 50 km/h at night; the low is near 0 C with a 30 per cent chance of flurries. Ignace stays near 7 C in periods of rain, with north gusts to 50 km/h before rain ends in the evening and the temperature falls to 0 C.

Fort Frances stays near 9 C as rain ends in the afternoon. North gusts reach 50 km/h and the overnight low is 1 C.

Armstrong stays near 6 C and receives 20 to 30 mm during the day, followed by another 10 to 20 mm at night. North winds gust to 50 km/h as rain tapers before morning and the low reaches -1 C. Greenstone, represented by Geraldton-Longlac-Caramat, stays near 8 C in 30 to 40 mm of heavy rain, with another 10 to 20 mm overnight and a low of 1 C.

Nipigon stays near 10 C in 30 to 40 mm of heavy rain. Another 10 to 20 mm is forecast Wednesday night, when north winds increase to 40 km/h with gusts to 60 and the low falls to 2 C.

Thursday: Colder air reaches the rain zone

Kenora reaches 6 C under a mix of sun and cloud. Red Lake reaches 4 C, while Dryden, Sioux Lookout and Ignace clear near 3 C. Fort Frances clears near 5 C. Thursday-night lows range from -4 C at Dryden, Red Lake and Ignace to -7 C at Fort Frances.

Farther east, Armstrong has a 60 per cent chance of rain and a high near 2 C before a low of -9 C. Greenstone gets periods of rain or snow and reaches 2 C, then falls to -5 C. Nipigon keeps a 60 per cent chance of rain near 4 C, followed by a 40 per cent chance of flurries or rain showers and a low near -6 C.

Friday: Dry and bright

Friday is sunny. Highs are about 6 C in Kenora, Red Lake, Dryden and Ignace; 5 C in Fort Frances and Sioux Lookout; 4 C in Armstrong and Nipigon; and 3 C in Greenstone. Clear Friday-night lows range from about 1 C in the western districts to -5 or -6 C around Greenstone and Armstrong.

Wardrobe

Use a waterproof shell and waterproof footwear from Armstrong to Nipigon. Drivers should keep a dry insulating layer in the vehicle and avoid water-covered roads. Add gloves and a warm mid-layer Thursday as rain begins to mix with snow and wet surfaces may turn icy after dark.

Weather trivia

One millimetre of rain equals one litre of water spread over one square metre. A 50 mm rainfall therefore places 50 litres of water on every square metre of level ground before runoff or absorption.

Source note: Environment Canada northern forecast; Environment Canada northern extended forecast; Environment Canada Ontario alerts; Environment Canada climate almanac.