If you only need Markham climate: monthly averages, the figures and table here are the whole story. Markham runs from -6.4 C in Jan to 22.1 C in Jul, a swing of 28.5 C. Rain is spread through the year, with Oct the wettest month at 2.26 mm/day and Feb the driest at 1.65 mm/day. Taken together that is roughly 721 mm of rain a year for the grid cell. Values come from a public open API; a successful result is cached so a later outage never blanks the page. The table underneath carries the per-month breakdown; the related pages cover the same dataset nearby.
Annual mean temperature 7.8 C
Warmest month Jul (22.1 C)
Coldest month Jan (-6.4 C)
Wettest month Oct (2.26 mm/day)
All-time record high 35.8 C
All-time record low -29.2 C
Annual precipitation 723 mm / year
Coordinates 43.86682, -79.2663
Population 338,503
Average monthly temperature and rainfall in Markham
Month
Mean temp (C)
Rain (mm/day)
Record high (C)
Record low (C)
Jan
-6.4
1.67
11.9
-26.9
Feb
-6.2
1.65
13.3
-29.2
Mar
-1.1
1.66
23.9
-28.2
Apr
5.2
2.19
24.3
-14.3
May
12.1
2.17
31.9
-3.2
Jun
18.2
2.20
34.6
3.5
Jul
22.1
2.08
35.6
7.8
Aug
21.4
1.79
35.8
9.6
Sep
17.4
1.96
33.4
3.4
Oct
9.7
2.26
28.3
-2.9
Nov
3.1
2.14
21.1
-13.3
Dec
-2.8
1.94
14.0
-20.9
What the Markham climate table shows
Values are multi-decadal climatological averages for the 43.86682, -79.2663 grid cell, not a single year. Rain is the daily mean, so a value of 2.00 mm/day is about 60 mm across a 30-day month. Averages smooth over extremes, so use them for planning rather than for what to pack for next Tuesday.
Frequently asked questions
Why do the numbers differ from a weather app?
An app shows one location on one day. These are long-run averages, so they smooth out single hot or cold spells.
How much rain is 2.26 mm/day in a month?
Rain is recorded as a daily mean, so 2.26 mm/day is roughly 69 mm across a 30-day month.