Ontario
May
Weather in Ontario for May 2025
Your guide to Ontario weather in May - trends and predictions
In general, the average temperature in Ontario at the beginning of May is 13.9 °C. As the month progressed, temperatures tended to significantly warm up, reaching an average of 20.7 °C by the end of May.
With an average of 3 rainy days, Ontario experiences minimal rainfall in May, ensuring that most days remain pleasantly dry.
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28
Dry days
3
Rainy days
0
Snow days
21°/8°
Temperatures
14 km/h
Avg max wind
64 %
Avg humidity
Ontario in May average weather
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| Mon. | Tue. | Wed. | Thu. | Fri. | Sat. | Sun. |
|---|---|---|---|---|---|---|
| 1  13° | 2  12° | 3 13° | 4  13° | |||
| 5  13° | 6  17° | 7 16° | 8 20° | 9 14° | 10 17° | 11 18° |
| 12 19° | 13 20° | 14 16° | 15  20° | 16  21° | 17 17° | 18 18° |
| 19 22° | 20 21° | 21 24° | 22 22° | 23 21° | 24 20° | 25 17° |
| 26 21° | 27 21° | 28 20° | 29 20° | 30 21° | 31 25° |
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Temperatures trend during May in Ontario
See the weather trend as well as the moving average line
May weather day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| 1 May | Heavy rain at times | 13° /5° | 1.5 mm | 3 | |
| 2 May | Moderate rain at times | 12° /5° | 2 mm | 3 | |
| 3 May | Moderate rain at times | 13° /7° | 4.6 mm | 3 | |
| 4 May | Patchy rain possible | 13° /8° | 0.8 mm | 4 | |
| 5 May | Overcast | 13° /8° | 1.2 mm | 3 | |
| 6 May | Partly cloudy | 17° /6° | 0 mm | 5 | |
| 7 May | Heavy rain at times | 16° /8° | 5.3 mm | 4 | |
| 8 May | Partly cloudy | 20° /10° | 0.2 mm | 5 | |
| 9 May | Partly cloudy | 14° /8° | 1.4 mm | 4 | |
| 10 May | Partly cloudy | 17° /8° | 0.1 mm | 5 | |
| 11 May | Overcast | 18° /8° | 0.5 mm | 4 | |
| 12 May | Partly cloudy | 19° /10° | 1.2 mm | 5 | |
| 13 May | Partly cloudy | 20° /11° | 7.1 mm | 5 | |
| 14 May | Overcast | 16° /9° | 13.8 mm | 4 | |
| 15 May | Sunny | 20° /8° | 0 mm | 5 | |
| 16 May | Cloudy | 21° /10° | 0 mm | 5 | |
| 17 May | Sunny | 17° /8° | 0 mm | 5 | |
| 18 May | Sunny | 18° /7° | 0 mm | 5 | |
| 19 May | Overcast | 22° /9° | 1.4 mm | 5 | |
| 20 May | Moderate or heavy rain shower | 21° /13° | 12.9 mm | 5 | |
| 21 May | Partly cloudy | 24° /13° | 1.6 mm | 6 | |
| 22 May | Cloudy | 22° /13° | 1.9 mm | 5 | |
| 23 May | Sunny | 21° /11° | 0.2 mm | 6 | |
| 24 May | Heavy rain at times | 20° /11° | 1.3 mm | 5 | |
| 25 May | Sunny | 17° /8° | 1.7 mm | 5 | |
| 26 May | Sunny | 21° /9° | 0 mm | 6 | |
| 27 May | Sunny | 21° /11° | 2.6 mm | 5 | |
| 28 May | Overcast | 20° /11° | 1.1 mm | 5 | |
| 29 May | Sunny | 20° /11° | 0 mm | 6 | |
| 30 May | Sunny | 21° /10° | 0 mm | 6 | |
| 31 May | Sunny | 25° /12° | 0 mm | 7 | |
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Important Notice
Our weather forecast for Ontario in May is based on the analysis of historical data rather than real-time forecast models. While this provides a general overview, weather conditions can change. We recommend that you check the Ontario forecast closer to your planned date for the most up-to-date weather information.
Ontario in May - FAQ
What are the expected maximum and minimum temperatures in Ontario during May?
Enjoy moderate daytime temperatures of up to 21° and cooler nights around 8°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in Ontario during May?
Significant rainfall exceeding 118.3 mm is expected in Ontario during May, occurring over more than 3 days. Preparing for wet conditions is recommended in your planning.
What are the typical wind conditions in Ontario during May?
The average wind speed in Ontario during May is 14 km/h, suggesting breezy to windy conditions, depending on your activities.
May rainfall patterns in Ontario
Explore the daily rainfall trends and prepare for Ontarios May weather 💧
UV exposure in Ontario during May
Stay informed about UV levels for safe outdoor activities throughout the month of May ☀️
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