St. Catharines
May
Weather in St. Catharines for May 2025
Your guide to St. Catharines weather in May - trends and predictions
In general, the average temperature in St. Catharines at the beginning of May is 12.1 °C. As the month progressed, temperatures tended to significantly warm up, reaching an average of 19.3 °C by the end of May.
With an average of 3 rainy days, St. Catharines experiences minimal rainfall in May, ensuring that most days remain pleasantly dry.
- New! Chat with our AI weatherman - it’s amazing and free.
28
Dry days
3
Rainy days
0
Snow days
18°/8°
Temperatures
18 km/h
Avg max wind
77 %
Avg humidity
St. Catharines in May average weather
Move between months or click on a day
| Mon. | Tue. | Wed. | Thu. | Fri. | Sat. | Sun. |
|---|---|---|---|---|---|---|
| 1  11° | 2  10° | 3  12° | 4 12° | |||
| 5  12° | 6  15° | 7 13° | 8 18° | 9 12° | 10  14° | 11 15° |
| 12 17° | 13 17° | 14  13° | 15 17° | 16 17° | 17 14° | 18 16° |
| 19 18° | 20 17° | 21 21° | 22 20° | 23 20° | 24 18° | 25 17° |
| 26 18° | 27 20° | 28 20° | 29 19° | 30 19° | 31 22° |
You can click on date
Access St. Catharines weather forecasts with a simple click. Select any date for comprehensive insights on temperature, rainfall, and wind conditions.
Temperatures trend during May in St. Catharines
See the weather trend as well as the moving average line
May weather day by day
Click on a date for more information
| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| 1 May | Patchy rain possible | 11° /5° | 0.5 mm | 3 | |
| 2 May | Heavy rain at times | 10° /5° | 3.2 mm | 3 | |
| 3 May | Moderate rain at times | 12° /6° | 5.4 mm | 3 | |
| 4 May | Patchy rain possible | 12° /7° | 0.8 mm | 3 | |
| 5 May | Overcast | 12° /7° | 0.8 mm | 3 | |
| 6 May | Sunny | 15° /7° | 0.1 mm | 5 | |
| 7 May | Heavy rain at times | 13° /7° | 3.2 mm | 3 | |
| 8 May | Overcast | 18° /9° | 1.1 mm | 4 | |
| 9 May | Moderate or heavy rain shower | 12° /8° | 4.2 mm | 3 | |
| 10 May | Partly cloudy | 14° /7° | 0.1 mm | 4 | |
| 11 May | Overcast | 15° /8° | 2.9 mm | 4 | |
| 12 May | Sunny | 17° /9° | 0.2 mm | 5 | |
| 13 May | Partly cloudy | 17° /10° | 5.9 mm | 5 | |
| 14 May | Cloudy | 13° /9° | 13.9 mm | 3 | |
| 15 May | Sunny | 17° /8° | 0 mm | 5 | |
| 16 May | Overcast | 17° /10° | 0 mm | 4 | |
| 17 May | Sunny | 14° /9° | 0.1 mm | 4 | |
| 18 May | Sunny | 16° /8° | 0.2 mm | 5 | |
| 19 May | Overcast | 18° /10° | 1.1 mm | 4 | |
| 20 May | Moderate or heavy rain shower | 17° /11° | 16.3 mm | 4 | |
| 21 May | Sunny | 21° /12° | 0.9 mm | 6 | |
| 22 May | Partly cloudy | 20° /12° | 2 mm | 5 | |
| 23 May | Cloudy | 20° /12° | 0.2 mm | 5 | |
| 24 May | Moderate rain at times | 18° /11° | 0.6 mm | 5 | |
| 25 May | Sunny | 17° /9° | 4.4 mm | 5 | |
| 26 May | Sunny | 18° /10° | 0 mm | 5 | |
| 27 May | Sunny | 20° /12° | 2 mm | 5 | |
| 28 May | Sunny | 20° /11° | 1.5 mm | 5 | |
| 29 May | Sunny | 19° /11° | 0 mm | 5 | |
| 30 May | Sunny | 19° /11° | 0 mm | 6 | |
| 31 May | Sunny | 22° /12° | 0 mm | 6 | |
| Next | |||||
Important Notice
Our weather forecast for St. Catharines 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 St. Catharines forecast closer to your planned date for the most up-to-date weather information.
St. Catharines in May - FAQ
What are the expected maximum and minimum temperatures in St. Catharines during May?
Enjoy moderate daytime temperatures of up to 18° and cooler nights around 8°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in St. Catharines during May?
Significant rainfall exceeding 127.3 mm is expected in St. Catharines during May, occurring over more than 3 days. Preparing for wet conditions is recommended in your planning.
What are the typical wind conditions in St. Catharines during May?
The average wind speed in St. Catharines during May is 18 km/h, suggesting breezy to windy conditions, depending on your activities.
Quick links
You are here
Where is St. Catharines?Get accurate weather forecasts for St. Catharines, located at latitude 43.171 and longitude -79.243. Stay updated with localized weather information tailored for St. Catharines.
Found a mistake?
We appreciate your attention to details. Tell us here.