Observed at: St. Catharines Airport
Date: Monday September 24, 2018 at 22:00 EDT
Temp.: 18.9 °C
Wind: SSE 19 km/h
Humidity: 68 %
Dew point: 12.9 °C
Pressure: 102.3 kPa
Tendency:
Sunrise: 07:06
Sunset: 19:12
Normals:
Max 19°C Min 10°C
Yesterday
  Max: °C
  Min: °C
  Rainfall: mm

 Extended Forecast - Environment Canada
  Tuesday
Chance of showers (70%)
Chance of showers
Max: 23°C
Wednesday
Chance of showers (60%)
Chance of showers
Max: 21°C
Thursday
Sunny
Sunny
Max: 18°C
Friday
A mix of sun and cloud
A mix of sun and cloud
Max: 18°C
Saturday
A mix of sun and cloud
A mix of sun and cloud
Max: 16°C
Sunday
A mix of sun and cloud
A mix of sun and cloud
Max: 16°C
Monday night
A few showers
A few showers
Min: 17°C
Tuesday night
A few showers
A few showers
Min: 20°C
Wednesday night
Cloudy periods
Cloudy periods
Min: 9°C
Thursday night
Cloudy periods
Cloudy periods
Min: 11°C
Friday night
Cloudy periods
Cloudy periods
Min: 9°C
Saturday night
Cloudy periods
Cloudy periods
Min: 10°C

Forecast

St. Catharines, ON (Issued: Monday September 24, 2018 at 15:30 EDT)

Tonight
Cloudy. A few showers beginning this evening. Amount 5 to 10 mm. Wind southeast 20 km/h gusting to 50 becoming south 40 gusting to 60 overnight. Low 17.
Tuesday
Cloudy with 70 percent chance of showers. Wind south 40 km/h gusting to 60. High 23. Humidex 30. UV index 4 or moderate.
Tuesday night
Showers with risk of a thunderstorm. Amount 15 to 25 mm. Wind southwest 30 km/h gusting to 50. Low 20.
Wednesday
Cloudy with 60 percent chance of showers. High 21.
Wednesday night
Cloudy periods. Low 9.
Thursday
Sunny. High 18.
Thursday night
Cloudy periods. Low 11.
Friday
A mix of sun and cloud. High 18.
Friday night
Cloudy periods. Low 9.
Saturday
A mix of sun and cloud. High 16.
Saturday night
Cloudy periods. Low 10.
Sunday
A mix of sun and cloud. High 16.
Averages and extremes
Highest temperature(1971-2000)22.9 °C1986
Lowest temperature(1971-2000)1.7 °C1974
Average high19.9 °C 
Average low10.1 °C 
Average15.0 °C 
Greatest rainfall(1971-2000)34.0 mm1977
Greatest snowfall(1971-2000)0.0 cm1971
Greatest precipitation(1971-2000)34.0 mm1977
Most snow on the ground(1971-2000)0.0 cm1971
Monthly frequency of precipitation36.0 % 

24 Hour Forecast - St. Catharines, ON

Date/Time
(EDT)
Temp.
(°C)

Weather Conditions

LOP †
Wind
(km/h)

Humidex
24 September 2018
23:00 18 A few showers (80%)  A few showers High SE 30 gust 50
25 September 2018
00:00 18 A few showers (80%)  A few showers High SE 30 gust 50
01:00 17 A few showers (80%)  A few showers High SE 30 gust 50
02:00 17 A few showers (80%)  A few showers High SE 30 gust 50
03:00 17 A few showers (80%)  A few showers High S 40 gust 60
04:00 17 A few showers (80%)  A few showers High S 40 gust 60
05:00 17 A few showers (80%)  A few showers High S 40 gust 60
06:00 17 Chance of showers (70%)  Chance of showers Medium S 40 gust 60
07:00 18 Chance of showers (70%)  Chance of showers Medium S 40 gust 60
08:00 18 Chance of showers (70%)  Chance of showers Medium S 40 gust 60
09:00 19 Chance of showers (70%)  Chance of showers Medium S 40 gust 60
10:00 19 Chance of showers (70%)  Chance of showers Medium S 40 gust 60
11:00 20 Chance of showers (70%)  Chance of showers Medium S 40 gust 60 25
12:00 21 Chance of showers (70%)  Chance of showers Medium SW 30 gust 50 26
13:00 22 Chance of showers (70%)  Chance of showers Medium SW 30 gust 50 28
14:00 23 Chance of showers (70%)  Chance of showers Medium SW 30 gust 50 30
15:00 23 Chance of showers (70%)  Chance of showers Medium SW 30 gust 50 30
16:00 23 Chance of showers (70%)  Chance of showers Medium SW 30 gust 50 30
17:00 23 Chance of showers (70%)  Chance of showers Medium SW 30 gust 50 30
18:00 23 A few showers (80%)  A few showers High SW 30 gust 50 30
19:00 22 A few showers (80%)  A few showers High SW 30 gust 50 29
20:00 22 A few showers (80%)  A few showers High SW 30 gust 50 29
21:00 22 A few showers. Risk of thunderstorms (80%)  A few showers. Risk of thunderstorms High SW 30 gust 50 29
22:00 22 A few showers. Risk of thunderstorms (80%)  A few showers. Risk of thunderstorms High SW 30 gust 50 29
 
† 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