Observed at: St. Catharines / Niagara District Airport
Date: Sunday June 20, 2021 at 21:00 EDT
Mostly Cloudy
Mostly Cloudy
Temp.: 23.6 °C
Humidex: 31
Wind: S 6 km/h
Humidity: 80 %
Dew point: 19.9 °C
Pressure: 100.4 kPa
Tendency: rising
Visibility: 24.1 km
Sunrise: 05:37
Sunset: 21:00
Normals:
Max 25°C Min 15°C
Yesterday
  Max: °C
  Min: °C
  Rainfall: mm

 Extended Forecast - Environment Canada
  Monday
Chance of showers or thunderstorms (60%)
Chance of showers or thunderstorms
Max: 26°C
Tuesday
A mix of sun and cloud
A mix of sun and cloud
Max: 20°C
Wednesday
Sunny
Sunny
Max: 23°C
Thursday
Sunny
Sunny
Max: 27°C
Friday
A mix of sun and cloud
A mix of sun and cloud
Max: 27°C
Saturday
Chance of showers (60%)
Chance of showers
Max: 26°C
Sunday night
Showers or thunderstorms
Showers or thunderstorms
Min: 18°C
Monday night
Chance of showers (60%)
Chance of showers
Min: 11°C
Tuesday night
Clear
Clear
Min: 12°C
Wednesday night
Clear
Clear
Min: 15°C
Thursday night
Cloudy periods
Cloudy periods
Min: 19°C
Friday night
Chance of showers (60%)
Chance of showers
Min: 19°C

Forecast

St. Catharines, ON (Issued: Sunday June 20, 2021 at 15:30 EDT)

Tonight
Partly cloudy. 30 percent chance of showers this evening. Showers with a few thunderstorms beginning near midnight. Risk of a thunderstorm this evening. Local amount 15 to 25 mm. Wind southwest 20 km/h. Low 18.
Monday
Showers with a few thunderstorms ending in the morning then mainly cloudy with 60 percent chance of showers. Risk of a thunderstorm late in the morning and in the afternoon. Wind south 20 km/h gusting to 40 becoming southwest 40 gusting to 70 in the morning. High 26. Humidex 35. UV index 7 or high.
Monday night
Cloudy. 60 percent chance of showers early in the evening with risk of a thunderstorm. Wind west 20 km/h gusting to 40. Low 11.
Tuesday
A mix of sun and cloud. High 20.
Tuesday night
Clear. Low 12.
Wednesday
Sunny. High 23.
Wednesday night
Clear. Low 15.
Thursday
Sunny. High 27.
Thursday night
Cloudy periods. Low 19.
Friday
A mix of sun and cloud. High 27.
Friday night
Cloudy with 60 percent chance of showers. Low 19.
Saturday
Cloudy with 60 percent chance of showers. High 26.
Averages and extremes
Highest temperature(1972-2000)32.9 °C1988
Lowest temperature(1972-2000)8.5 °C1992
Average high24.9 °C 
Average low14.0 °C 
Average19.5 °C 
Greatest rainfall(1972-2000)14.2 mm1989
Greatest snowfall(1972-2000)0.0 cm1972
Greatest precipitation(1972-2000)14.2 mm1989
Most snow on the ground(1972-2000)0.0 cm1972
Monthly frequency of precipitation36.0 % 

24 Hour Forecast - St. Catharines, ON

Date/Time
(EDT)
Temp.
(°C)

Weather Conditions

LOP †
Wind
(km/h)

Humidex
20 June 2021
22:00 24 Chance of showers. Risk of thunderstorms (30%)  Chance of showers. Risk of thunderstorms Low SW 20 31
23:00 22 Chance of showers. Risk of thunderstorms (30%)  Chance of showers. Risk of thunderstorms Low S 10 29
21 June 2021
00:00 21 Showers or thunderstorms (100%)  Showers or thunderstorms High S 10 28
01:00 20 Showers or thunderstorms (100%)  Showers or thunderstorms High S 10 27
02:00 19 Showers or thunderstorms (100%)  Showers or thunderstorms High S 10
03:00 19 Showers or thunderstorms (100%)  Showers or thunderstorms High S 10
04:00 18 Showers or thunderstorms (100%)  Showers or thunderstorms High S 10
05:00 18 Showers or thunderstorms (100%)  Showers or thunderstorms High S 20
06:00 19 Showers or thunderstorms (100%)  Showers or thunderstorms High S 20
07:00 20 Showers or thunderstorms (100%)  Showers or thunderstorms High S 20 27
08:00 21 Showers or thunderstorms (100%)  Showers or thunderstorms High S 20 gust 40 29
09:00 22 Showers or thunderstorms (100%)  Showers or thunderstorms High SW 40 gust 70 30
10:00 24 Chance of showers. Risk of thunderstorms (60%)  Chance of showers. Risk of thunderstorms Medium SW 40 gust 70 32
11:00 25 Chance of showers. Risk of thunderstorms (60%)  Chance of showers. Risk of thunderstorms Medium SW 40 gust 60 34
12:00 25 Chance of showers. Risk of thunderstorms (60%)  Chance of showers. Risk of thunderstorms Medium SW 40 gust 60 34
13:00 25 Chance of showers. Risk of thunderstorms (60%)  Chance of showers. Risk of thunderstorms Medium SW 40 gust 60 33
14:00 25 Chance of showers. Risk of thunderstorms (60%)  Chance of showers. Risk of thunderstorms Medium SW 40 gust 60 33
15:00 25 Chance of showers. Risk of thunderstorms (60%)  Chance of showers. Risk of thunderstorms Medium SW 40 gust 60 33
16:00 26 Chance of showers. Risk of thunderstorms (60%)  Chance of showers. Risk of thunderstorms Medium SW 40 gust 60 35
17:00 26 Chance of showers. Risk of thunderstorms (60%)  Chance of showers. Risk of thunderstorms Medium W 30 35
18:00 24 Chance of showers. Risk of thunderstorms (60%)  Chance of showers. Risk of thunderstorms Medium W 30 32
19:00 22 Chance of showers. Risk of thunderstorms (60%)  Chance of showers. Risk of thunderstorms Medium W 20 gust 40 29
20:00 20 Chance of showers. Risk of thunderstorms (60%)  Chance of showers. Risk of thunderstorms Medium W 20 gust 40 25
21:00 18 Mainly cloudy (0%)  Mainly cloudy Nil W 20 gust 40
 
† Likelihood of Precipitation (LOP) as described in the public forecast as a chance of measurable precipitation for a period of time.
  Nil: 0%
  Low: 40% or below
  Medium: 60% or 70%
  High: Above 70%
‡ Value not significant

Environment Canada