Weather in St. John's in May

The month to avoid. May is the month most people should skip in St. John's. Highs sit at 5.8 °C and the day is short; this is an indoors-with-excursions month, not an outdoors-all-day one.

May ranks 6 of 12 in St. John's: past the worst of the year but short of August, which is the month to book if the dates are open.

This is persistent light rain rather than storms: 16 wet days but only 2 heavy ones. It rarely cancels anything outright, and it rarely fully clears either. A jacket beats an umbrella. Layers, and a genuinely waterproof outer — at 5.8 °C the difference between a good day and a miserable one is entirely down to what you are wearing.

What the averages hide

Averages flatten a month, and this one hides a few things: the day barely swings — 3.7 °C between the overnight low and the afternoon high. Across the twenty years measured, the hottest May day reached 16.5 °C and the coldest night fell to -2 °C, and the wettest single day dropped 34 mm — roughly 38% of the month's rain in one day.

May is one of the reliable ones — rainfall has stayed between 54 mm and 123 mm across all twenty years, a narrow enough band that the 90 mm average is something you can plan against rather than merely quote.

Wind is light at 15.2 km/h, so the temperature on the page is close to the temperature on your skin, and humidity runs at 90%, which at 5.8 °C means damp rather than muggy — the kind of cold that gets into a coat and stays there.

How May sits in the year

The month is on the way up: 3 °C warmer than April, and June adds another 4.2 °C. Late in the month feels noticeably different from the start of it, which is worth knowing if the trip is short.

Daylight in May

15.1 hours of daylight, gaining 1.3 hours across the month. That is between St. John's's extremes of 15.9 and 8.5 hours, so days are long enough not to constrain the plan.

Sea temperature

The sea sits at about 1.9 °C in May — too cold to swim without a wetsuit. The sea peaks at 14.2 °C in August and bottoms out at -1 °C — water lags the air by a month or two, which is why the best swimming often comes after the best weather.

How busy it gets

Quiet. Few other visitors, cheaper rooms, and a real chance some seasonal operators are shut.

Crowd levels are estimated from climate desirability and school-holiday calendars, not from visitor numbers.

May in St. John's versus nearby

If St. John's is one option among several, the nearby comparison is worth making. Sydney is a better bet in May — 4.6 °C warmer, 2 days less rain. Halifax is a better bet in May — 5.7 °C warmer, 3 days less rain.

So: May is a compromise. August is 39 points better and is what St. John's is actually like at its best — worth moving the trip for if that is possible, and worth adjusting expectations for if it is not.

Every month in St. John's

See all twelve months in St. John's, or where else to go in May.