July 2026 Storms in Northwestern Ontario: Kenora Tornado Warnings, Thunder Bay Hail Risk
July 2026 has been an active storm month across Northwestern Ontario. Kenora took the worst of it, and Thunder Bay spent two separate days under severe thunderstorm alerts with damaging hail in the forecast. Here is what actually happened, with sourced numbers, and what it means for your roof.
July 6: the Kenora storm
A violent storm system triggered red-coded tornado warnings for Kenora and Dryden, Environment Canada’s most severe alert level. Kenora recorded 94 mm of rain in a short period, close to 10 cm, flooding roads across the city. More than 4,200 Hydro One customers lost power along the Highway 17 corridor between the Manitoba boundary and Highway 71, and downed and damaged trees were reported in the Bergland area. The Northern Tornadoes Project at Western University sent a field team to determine whether tornadoes touched down (NWONewsWatch).
For roofs, an event like this does damage three ways at once: wind lifts and creases shingles, falling limbs puncture decks, and that volume of rain finds every weak point in flashing and valleys. If a tree or branch contacted your roof during this storm, get it inspected even if it looks fine from the ground. Deck damage under intact shingles is invisible from the street and shows up later as a leak.
July 12: quarter-size hail tracked over Thunder Bay
Environment Canada issued a severe thunderstorm warning as a storm moved east at 50 km/h from the Boulevard Lake area toward Cloud Bay-Dorion and Sleeping Giant Provincial Park. The warning called for wind gusts to 90 km/h, hail up to quarter size, and 15 to 50 mm of rain (Your ThunderBay).
Quarter-size hail is right at the threshold where asphalt shingles start taking real damage. It knocks granules loose and bruises the mat underneath, and the bruise weathers into a crack a season or two later. The tell is on your soft metal: check eavestroughs, downspouts, and roof vents for dents. If the aluminum took hits, the shingles did too.
July 20: storms and smoke on the same day
Thunder Bay closed out the stretch under a severe thunderstorm watch and an air quality warning at the same time, with west winds gusting to 70 km/h forecast and wildfire smoke cutting visibility to 5 km (NetNewsLedger). Environment Canada’s Thunder Bay CS station measured a 51 km/h gust and 14.3 mm of rain that day.
What to check now
A ground-level pass takes ten minutes:
- Scan ridges, rakes, and eaves with binoculars for creased, lifted, or missing shingles. Wind concentrates at the edges.
- Check eavestroughs and the ground below downspouts for shingle granules. A sudden dump after a storm means hail or wind scouring.
- Look for dents in vents, flashing, eavestroughs, and any other soft metal. This is also the clearest evidence an insurance adjuster can work with.
- After the next heavy rain, check the attic for damp insulation or new staining.
Why we log these events
Insurance claims are far easier when damage is tied to a documented storm with a date and a source. We keep a running, sourced log of severe weather across the region on our Northwestern Ontario Storm Damage Tracker, so the record is there if you ever need it. And if you want eyes on your roof after this month’s weather, get in touch for an inspection. We document what we find in writing either way.