St. John's NL Average Temperatures by Month

The numbers here tell you how hot and cold the weather usually is in St. John's, Newfoundland during each month of the year.

The average high and low temperatures are listed below monthly and annually for the city, in both degrees Fahrenheit and Celsius.

Maximums and minimums are only part of the temperature picture. To fill in the rest, there's information on how many days a month get above or below a given temperature.

To find out how often it rises over 10 or 20 °C each month in St. John's, scroll down farther. There are also monthly and yearly counts of days with frost and cold weather.

The first set of high and low temperatures are averages for 2010 to 2019. Everything else here is based on 1981 to 2010 weather.

10-year temperature averages for St. John's, 2010 to 2019
High °F	Low °F		High °C	Low °C
33	21	January	1	-6
31	19	February	-1	-7
34	22	March	1	-6
43	28	April	6	-2
51	35	May	11	2
59	42	June	15	6
70	53	July	21	12
69	55	August	21	13
63	48	September	17	9
53	40	October	12	4
44	32	November	7	0
35	25	December	2	-4
49	35	Year	9	1

30-year temperature averages for St. John's, 1981 to 2010
High °F	Low °F		High °C	Low °C
31	17	January	-1	-8
30	16	February	-1	-9
34	21	March	1	-6
42	29	April	6	-2
52	35	May	11	2
60	43	June	16	6
69	52	July	21	11
69	53	August	20	12
62	47	September	17	8
51	39	October	11	4
43	31	November	6	0
35	24	December	2	-5
48	34	Year	9	1

Days of Hot Weather in St. John's

A hot day at St John's means highs in the twenties Celsius. About half of the summer days here get that warm. The thermometer can nudge above 30 °C (86 °F), but that doesn't happen often, only once or twice a decade.

Days per month in St. John's above 10 or 20 °C
	10 °C 50 °F	20 °C 68 °F
January	1	0
February	1	0
March	1	0
April	5	0
May	17	2
June	25	7
July	31	19
August	31	18
September	28	6
October	16	0
November	7	0
December	2	0
Year	165	53

When St. John's Has Frosty Weather

St. John's typically has 167 days a year when the minimum temperature is at 0 °C or below. The average date for the last frost in spring is May 30. Frost normally returns here on October 17. The frost-free period extends for 139 days on average between the final spring frost and the first fall frost.

Average number of days with freezing temperatures in St. John's
	0 °C 32 °F
January	30
February	27
March	29
April	23
May	9
June	1
July	0
August	0
September	0
October	4
November	16
December	26
Year	167

How Often St. John's Has Cold Temperatures

The chilliest winter nights at St. John's usually have lows between -10 and -20 °C (14 and -4 °F). Temperatures below -20 °C do happen, but not every year. Lows of less than -30 °C (-22 °F) are not normal here.

From November to May, it can remain below freezing here all day long. St. John's typically has 66 days a year when the temperature never rises above 0 °C.

Days per month on average in St. John's when the minimum temperature drops below -2 or -10 °C
	-2 °C 28 °F	-10 °C 14 °F
January	28	11
February	25	12
March	25	7
April	13	0
May	3	0
June	0	0
July	0	0
August	0	0
September	0	0
October	2	0
November	10	0
December	21	5
Year	126	35

St. John's Temperatures: Averages by Month

Days of Hot Weather in St. John's

When St. John's Has Frosty Weather

How Often St. John's Has Cold Temperatures

References

More on Weather in Newfoundland & Labrador