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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.

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Average dry days
28
Dry days
Average rainy days
3
Rainy days
Average snowy days
0
Snow days
Average temperatures
18°/8°
Temperatures
Average wind speed
18 km/h
Avg max wind
Average humidity
77 %
Avg humidity

St. Catharines in May average weather

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Temperatures trend during May in St. Catharines

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 Patchy rain possible
Patchy rain possible
11° /5° 0.5 mm 3
2 May Heavy rain at times
Heavy rain at times
10° /5° 3.2 mm 3
3 May Moderate rain at times
Moderate rain at times
12° /6° 5.4 mm 3
4 May Patchy rain possible
Patchy rain possible
12° /7° 0.8 mm 3
5 May Overcast
Overcast
12° /7° 0.8 mm 3
6 May Sunny
Sunny
15° /7° 0.1 mm 5
7 May Heavy rain at times
Heavy rain at times
13° /7° 3.2 mm 3
8 May Overcast
Overcast
18° /9° 1.1 mm 4
9 May Moderate or heavy rain shower
Moderate or heavy rain shower
12° /8° 4.2 mm 3
10 May Partly cloudy
Partly cloudy
14° /7° 0.1 mm 4
11 May Overcast
Overcast
15° /8° 2.9 mm 4
12 May Sunny
Sunny
17° /9° 0.2 mm 5
13 May Partly cloudy
Partly cloudy
17° /10° 5.9 mm 5
14 May Cloudy
Cloudy
13° /9° 13.9 mm 3
15 May Sunny
Sunny
17° /8° 0 mm 5
16 May Overcast
Overcast
17° /10° 0 mm 4
17 May Sunny
Sunny
14° /9° 0.1 mm 4
18 May Sunny
Sunny
16° /8° 0.2 mm 5
19 May Overcast
Overcast
18° /10° 1.1 mm 4
20 May Moderate or heavy rain shower
Moderate or heavy rain shower
17° /11° 16.3 mm 4
21 May Sunny
Sunny
21° /12° 0.9 mm 6
22 May Partly cloudy
Partly cloudy
20° /12° 2 mm 5
23 May Cloudy
Cloudy
20° /12° 0.2 mm 5
24 May Moderate rain at times
Moderate rain at times
18° /11° 0.6 mm 5
25 May Sunny
Sunny
17° /9° 4.4 mm 5
26 May Sunny
Sunny
18° /10° 0 mm 5
27 May Sunny
Sunny
20° /12° 2 mm 5
28 May Sunny
Sunny
20° /11° 1.5 mm 5
29 May Sunny
Sunny
19° /11° 0 mm 5
30 May Sunny
Sunny
19° /11° 0 mm 6
31 May Sunny
Sunny
22° /12° 0 mm 6
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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.

May rainfall patterns in St. Catharines

Explore the daily rainfall trends and prepare for St. Cathariness May weather 💧

UV exposure in St. Catharines during May

Stay informed about UV levels for safe outdoor activities throughout the month of May ☀️

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Location coordinates 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.

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