May Temperatures in Ontario

Average temperatures for May at cities, towns and parks throughout Ontario are given below.

You can jump to a separate table for each section of the province: Eastern, Central, Southwestern, Northeastern and Northwestern Ontario.

The tables list the normals for maximum and minimum monthly temperatures, in degrees Celsius and Fahrenheit, based on weather data collected from 1981 to 2010.

Eastern Ontario

Average May temperatures
High °F	Low °F	Place	High °C	Low °C
66	48	Belleville	19	9
67	47	Cornwall	19	9
62	45	Kingston	16	7
66	46	Ottawa	19	8
66	40	Pembroke	19	4

Central Ontario

Average daily temperatures in May
High °F	Low °F	Place	High °C	Low °C
64	44	Barrie	18	7
67	46	Brantford	19	8
64	41	French River, Chaudiere Dam	18	5
65	46	Hamilton	19	8
64	42	Huntsville	18	6
65	42	Midland	18	6
67	48	Niagara Falls	19	9
62	46	Oshawa	17	8
66	46	Peterborough	19	8
67	46	St Catharines	19	8
65	50	Toronto	18	10

Southwestern Ontario

May temperatures: daily averages
High °F	Low °F	Place	High °C	Low °C
68	49	Chatham-Kent	20	9
65	43	Guelph	18	6
66	45	London	19	7
62	43	Owen Sound	17	6
64	49	Point Pelee National Park	18	9
65	45	Sarnia	18	7
65	44	Waterloo	18	6
69	49	Windsor	20	10

Northeastern Ontario

Average May temperatures
High °F	Low °F	Place	High °C	Low °C
61	37	Chapleau	16	3
61	42	Gore Bay	16	5
61	36	Kapuskasing	16	2
56	32	Moosonee	13	0
62	42	North Bay	17	6
62	39	Sault Ste Marie	16	4
58	41	South Baymouth	15	5
63	41	Sudbury	17	5
62	37	Timmins	17	3
58	35	Wawa	15	1

Northwestern Ontario

Average May temperatures
High °F	Low °F	Place	High °C	Low °C
62	39	Atikokan	17	4
54	31	Big Trout Lake	12	0
62	41	Dryden	17	5
64	40	Fort Frances	18	4
62	43	Kenora	17	6
61	37	Red Lake	16	3
61	36	Thunder Bay	16	2

Average Temperatures for Ontario in May

Eastern Ontario

Central Ontario

Southwestern Ontario

Northeastern Ontario

Northwestern Ontario

Reference

More Ontario Weather Information