The best times to visit Thornhill for ideal weather are
May 21st to September 30th
based on average temperature and humidity from NOAA (the National Oceanic and Atmospheric Administration). Read below for more weather and travel details.
Thornhill Travel Guide
Other Thornhill Travel Info
Weather in Thornhill
Average temperatures in Thornhill vary drastically. Considering humidity, temperatures feel cold for about half of the year and otherwise nice with a chance of rain or snow throughout most of the year. The area is less temperate than some — in the 26th percentile for pleasant weather — compared to tourist destinations worldwide. Weeks with ideal weather are listed above. If you’re looking for the very warmest time to visit Thornhill, the hottest months are July, August, and then June. See average monthly temperatures below. The warmest time of year is generally mid July where highs are regularly around 84.2°F (29°C) with temperatures rarely dropping below 60.6°F (15.9°C) at night.
Thornhill Temperatures (Fahrenheit)
Thornhill Temperatures (Celsius)
The way we experience weather isn’t all about temperature. Higher temperatures affect us much more at higher humidity, and colder temperatures feel piercing with high winds. Our perceived temperatures factor in humidity and wind chill to better represent how hot or cold the day feels to a person.
Thornhill Perceived Temperature (F)
Thornhill Perceived Temperature (C)
Average Thornhill Temperatures by Month
Daily highs (averaged for the month) usually give the best indication of the weather. A significantly lower mean and low generally just means it gets colder at night.
|Month||Avg. High (°F)||Avg. Mean (°F)||Avg. Low (°F)|
|Month||Avg. High (°C)||Avg. Mean (°C)||Avg. Low (°C)|
Precipitation (Rain or Snow)
If dry weather is what you’re after, the months with the lowest chance of significant precipitation in Thornhill are March, February, and then August. Note that we define “significant precipitation” as .1 inches or more in this section. The lowest chance of rain or snow occurs around early to mid February. For example, on the week of February 12th there is 1 day of precipitation on average. By contrast, it’s most likely to rain or snow in late July with an average of 3 days of significant precipitation the week of July 23rd.
When can you find snow in Thornhill? Weather stations report large amounts of snow likely to be deepest around February, especially close to early March. The best time to ski (if at all) in Thornhill is often around around December 17th when fresh powder is deepest. Please note that a value of 0 for snow in the graph below may either mean there was no snow, or that snow is unreported.
Chance of Precipitation
The graph below shows the % chance of rainy and snowy days in Thornhill.
Snow on the Ground
The graph below shows the average snow on the ground in Thornhill (in).
Average Rain and Snow by Month
|Month||Daily Chance of Rain||Average Snow Depth (in)||Total Precipitation (in)|
|Month||Daily Chance of Rain||Average Snow Depth (cm)||Total Precipitation (cm)|
Humidity and Wind
Thornhill has some high humidity months, with other comfortably humid months. The least humid month is April (52.3% relative humidity), and the most humid month is December (69.3%).
Wind in Thornhill is usually calm. The windiest month is April, followed by March and February. April’s average wind speed of around 7.5 knots (8.6 MPH or 13.8 KPH) is considered “a gentle breeze.” Maximum sustained winds (the highest speed for the day lasting more than a few moments) are at their highest in late April where average top sustained speeds reach 12.3 knots, which is considered a moderate breeze.
Relative Humidity (%)
The graph below shows the average % humidity by month in Thornhill.
The graph below shows wind speed (max and average) in knots.
Average Wind Speeds
Show Wind Speeds
All wind speeds are in knots. 1 knot = 1.15 MPH or 1.85 KPH.
|Month||Avg. Wind||Avg. Wind Feel||Sustained High Wind||High Wind Feel|
|Jan||6.8||Light breeze||10.3||Gentle breeze|
|Feb||7||Gentle breeze||10.7||Gentle breeze|
|Mar||7||Gentle breeze||10.7||Gentle breeze|
|Apr||7.5||Gentle breeze||11.9||Significant breeze|
|May||6.2||Light breeze||9.9||Gentle breeze|
|Jun||5.8||Light breeze||9.2||Gentle breeze|
|Jul||5.4||Light breeze||8.6||Gentle breeze|
|Aug||5||Light breeze||8.5||Gentle breeze|
|Sep||4.8||Light breeze||8.2||Gentle breeze|
|Oct||5.5||Light breeze||9.2||Gentle breeze|
|Nov||6||Light breeze||9.6||Gentle breeze|
|Dec||6.8||Light breeze||10.1||Gentle breeze|
Show Relative Humidity by Month
|Month||Avg. Relative Humidity|
Is it Safe to Travel to Thornhill?
Our best data indicates this area is generally safe. As of Oct 07, 2019 there are no travel advisories or warnings for Canada; exercise normal security precautions. Check this page for any recent changes or regions to avoid: Travel Advice and Advisories. This advisory was last updated on Oct 07, 2019.
The Busiest and Least Crowded Months
The busiest month for tourism in Thornhill, ON, Canada is July, followed by August and June. Prices for hotels and flights will be most expensive during these months, though you can save if you purchase well in advance. Tourists are unlikely to visit Thornhill in December. Those willing to visit at these times will likely find it the least expensive month.
Estimated Tourism by Month
Most Popular Months to Visit
Overall Thornhill Travel Experience by Season
Spring (March through May)
Humidity and temperatures combine to make this season feel moderately cold. Highs range from 76.1°F (24.5°C) and 32°F (0°C) with far warmer temperatures in the later months. Rain is somewhat common with 5 to 7 days of significant precipitation per month. Spring is the second busiest for tourism, which makes it a good time for those looking for things to do.
Summer (June through August)
The middle-year months have very comfortable weather with high temperatures that are comfortable. These months see the most precipitation with 6 to 10 days of precipitation per month. June – August is the busiest season for tourism in Thornhill, so lodging and other accommodations may cost more than usual.
Fall (September through November)
Fall daily highs range from 78.8°F (26°C) and 41.7°F (5.4°C), which will feel chilly given the humidity and wind. It rains or snows a significant amount: 6 to 8 days per month. Tourism is the slowest during these months due to the weather, so hotels may be affordably priced.
Winter (December through February)
Weather is far too cold this time of year in Thornhill to be enjoyable for warm weather travelers. The average high during this season is between 37.9°F (3.3°C) and 27°F (-2.8°C). On average, it rains or snows a fair amount: 5 to 7 times per month. These times of year are fairly slow with tourists.