Ranking cities by weather

Let’s analyze data from https://darksky.net from the last 10 years to compare weather (technically “climate”) in a selection of North American cities.

If we define a “nice day” as one where

• there are at least 10 hours of daylight,
• the high apparent temperature is at least 0°C and at most 30°C,
• the cloud cover is at most 70%, and
• the UV index is at most moderate (unfortunately I used UV index at a single point in time during the day and didn’t adjust for time zones),

we get:

What are the nicest months to visit Toronto?

If we define a “sunny day” as one where

• there are at least 10 hours of daylight,
• the high apparent temperature is at least 15°C, and
• the cloud cover is at most 50%,

we get:

What are the sunniest months to visit Toronto?

Lastly, if we define a “warm day” as one where

• the high apparent temperature is at least 15°C and at most 25°C and
• the UV index is at most high,

we get:

What are the warmest months to visit Toronto?