South Portland Weather in May

May in South Portland typically sees daytime highs of 18°C (64°F) and nighttime lows of 8°C (46°F). Rainfall is also possible this month, so it's worth packing an umbrella.

Rainfall in South Portland in May

You can expect rain on roughly 13 days based on historical data, averaging 107 mm (4.2 in) for the month. Rainfall intensity is on the higher side this month. Expect more substantial showers rather than light, passing rain.

Temperature in South Portland in May

If you're visiting South Portland in May, expect highs of 18°C (64°F) and overnight lows around 8°C (46°F). Even when the weather is stable, mornings and evenings can still feel distinctly cool. Nights drop to 8°C (46°F). Cold nights like these are actually great for sleeping well, as long as you have a warm enough duvet.

Sunshine in South Portland in May

The days are predominantly sunny, with an estimated total of around 244 hours of sunshine. These sun-filled days are perfect for playing sports, visiting parks, or going for a bike ride.

Average water temperature in May

The water temperature is only 8°C (46°F) this month, cold enough that most people will want to stay out. Hardy swimmers may manage a quick dip, but it won't be comfortable.

If you prefer dry days with pleasant temperatures, June, July, August and September typically offer the best circumstances. If you're seeking pleasant, dry and sunny weather somewhere else in the world, our weather planner can help you explore other options.