Discover the best time of year, based on historical climate, temperature, and precipitation.
The best time to visit London is May, June, September, when the weather, flight prices, and crowds align. — consistent weather climate
☀️Pleasant
| Score | 10 | 12 | 12 | 31 | 80 | 78 | 78 | 78 | 84 | 51 | 14 | 10 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Climate | Polar | Polar | Cold | Cold | Mild | Humid | Humid | Humid | Pleasant | Cold | Cold | Cold |
| Temperature | -8–0°C | -8–1°C | -3–6°C | 2–12°C | 9–20°C | 14–24°C | 17–27°C | 17–26°C | 14–23°C | 8–15°C | 1–8°C | -3–3°C |
| Feels like | -13–-5°C | -13–-4°C | -8–2°C | -2–9°C | 6–19°C | 13–25°C | 17–28°C | 17–27°C | 13–23°C | 5–13°C | -3–4°C | -8–-1°C |
| Precipitation | 81mm 15 days | 69mm 13 days | 83mm 12 days | 100mm 12 days | 77mm 10 days | 102mm 10 days | 99mm 10 days | 95mm 10 days | 65mm 8 days | 99mm 12 days | 72mm 12 days | 77mm 13 days |
| Sunshine | 2.9h ☀︎ 31% | 5.0h ☀︎ 47% | 6.4h ☀︎ 54% | 7.9h ☀︎ 59% | 10.5h ☀︎ 72% | 12.2h ☀︎ 79% | 12.4h ☀︎ 82% | 11.2h ☀︎ 81% | 9.9h ☀︎ 79% | 6.4h ☀︎ 58% | 4.7h ☀︎ 48% | 2.7h ☀︎ 30% |
| Wind | W · 21 km/h | W · 22 km/h | W · 22 km/h | W · 21 km/h | W · 19 km/h | W · 19 km/h | W · 16 km/h | W · 16 km/h | S · 17 km/h | SW · 20 km/h | SW · 21 km/h | SW · 21 km/h |
| Humidity (%) | 77% | 74% | 69% | 68% | 67% | 68% | 72% | 75% | 75% | 75% | 75% | 79% |
| Day length | 9.4h | 10.5h | 12.0h | 13.4h | 14.7h | 15.3h | 15.0h | 13.9h | 12.5h | 11.0h | 9.7h | 9.1h |
| Tourist Crowds | Low season | Low season | Low season | Shoulder season | Shoulder season | High season | High season | High season | High season | Shoulder season | Shoulder season | Shoulder season |
One of Canada's largest world music and arts festivals fills downtown London with free outdoor concerts, dance, and inte…
A long-running agricultural fair with rides, livestock shows, and live entertainment marks the transition from summer to…
Conventional wisdom crowns September as the crown jewel of southwestern Ontario, but London is actually best experienced in May, right when the river paths bloom and the city exhales before the summer humidity sets in.
Straddling the forks of the Thames River halfway between Toronto and Detroit, London is an anchor city shaped by massive collegiate campuses and dense Carolinian tree canopies. It rarely features on international bucket lists, functioning instead as a regional nexus of medicine, academia, and commerce. Because of that everyday working nature, the city's calendar marches to an unusual drumbeat. Standard tourism logic would steer you toward late summer or the early autumn harvest, but doing so walks you straight into packed avenues and high-season lodging premiums. If you want to understand what makes this river-threaded hub genuinely charming, you need to understand how the seasons warp both the weather and the population.
A pure weather spreadsheet will try to persuade you that September is London's finest hour. The math looks neat on paper: golden sunlight, comfortable afternoons, and crisp evenings. But travel is lived on pavements and in parks, not in spreadsheets, and that is why May is the quiet champion of the year.
In May, the heavy grey ceiling that smothers southwestern Ontario for half the year finally shatters. The city undergoes a physical loosening. Temperatures climb into the low twenties, bringing days that feel clean, warm, and bright without the muggy weight that settles over the low-lying river basin later in the summer. Along the Thames River, the park paths burst into shocking greens as the willow trees leaf out and wild trilliums speckle the woods.
More importantly, May offers a rare social lull. The massive student contingent at Western University has packed up and departed after spring exams, instantly draining tens of thousands of temporary residents from the streets. The rush of summer family travel has not yet arrived. The consequence is a city with wide open elbows: riverside trails are tranquil, downtown patios have immediate tables, and the surrounding countryside feels fresh and receptive rather than exhausted.
Come June, summer arrives with unmistakable force. Southwestern Ontario sits on a flat agricultural peninsula pinched between the Great Lakes, meaning moisture gathers quickly. Midsummer days hover in the high twenties, but the ambient humidity pushes the real sensation several degrees hotter, turning midafternoon strolls through unshaded downtown corridors into a heavy, slow-motion affair.
Yet this heat is precisely what fuels the city's outdoor culture. July brings Sunfest to Victoria Park, transforming the green lawns into a dense, swirling carnival of global music, brass bands, artisan stalls, and smoke from cross-cultural street kitchens. It is one of the premier world-music gatherings in the country, and for a long weekend, the downtown core feels magnetic and genuinely cosmopolitan. The grass fills with blankets, the perimeter streets hum, and the air stays balmy deep past midnight.
By August, the heat settles into a thick routine. Thunderstorms gather on humid late afternoons, releasing dramatic, short-lived downpours that steam off the asphalt before clearing into warm, buggy twilight. It is a lively, sun-drenched season, but you must be prepared to share every patio and park bench with peak summer crowds.
September provides the cleanest, crispest weather of the calendar. Rain drops to its lowest volume of the year, humidity vanishes, and the afternoons sit in that rare, perfect pocket where a light shirt suffices by day and a woolen sweater is welcome by dusk. In the surrounding Middlesex farmland, harvest displays appear and apple orchards fill up.
This is also when the historic Western Fair arrives, bringing rides, livestock competitions, and deep-fried carnival staples that summon families from every corner of southwestern Ontario. It marks the traditional hinge where late summer gives way to fall. Soon after, the canopy of the 'Forest City' ignites into vibrant amber and scarlet, particularly where the North Thames River winds past the collegiate bluffs.
There is, however, a serious catch that typical guides gloss over. September triggers the return of the student population, nearly doubling the energy—and congestion—of the central neighborhoods overnight. Traffic tightens, rental prices spike, and quiet corners vanish. While October preserves some of the stunning foliage, it introduces cold snaps and damp rains that quickly strip the trees bare. September is visually magnificent, but you pay for that polish in crowds and bustle.
Winter in London is long, biting, and intensely grey. The city lies directly downwind of Lake Huron, placing it squarely in the path of ferocious lake-effect snowbelts. Between December and February, icy winds sweep across flat farm fields to dump sudden, blinding squalls that can bury sidewalks under knee-deep drifts in an afternoon. Apparent temperatures regularly plunge well below freezing, and the sun rarely breaks through the persistent low cloud deck.
Yet the most astonishing calendar paradox occurs in March. By any objective climatic standard, March is miserable: daytime highs hover barely above freezing, snow transforms into grey, salt-stained slush, and biting drizzle chills you to the bone. Yet March records the highest crowd levels of the entire year.
The culprit is London's status as a regional heavyweight for healthcare, administration, and university life. March brings collegiate term deadlines, athletic playoffs, and regional conferences, flooding downtown hotels and dining rooms even as sleet spatters against the glass. By April, the freeze softens into a muddy, protracted thaw punctuated by frequent downpours. Unless your visit is strictly tied to campus business, do not be seduced into an early spring trip. Hold your nerve and wait for May.