The highest day temperature in May 2025 was 61°F. The lowest night temperature was 28°F. The average values for day and night temperatures during May were 43.0°F и 37.9°F respectivly.

The average sea surface temperature in May 2025 for St. John's was 35.3°F. The maximum and minimum values were 32.8°F and 37.2°F respectively.

Most of the days in May are gloomy but you can also expect sunny days.

Precipitation total in May for St. John's is 1.6 in.

The average wind speed in May is 11.7 mph. It makes May one of the most windless months of the year for St. John's.

We are using day length and cloud cover information for each day of the month to calculate averages for this chart. Average sunny hours for St. John's in May is 5.4 hours.