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St. Catharines, Ontario

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St. Catharines, Ontario Weather
Today WinterCast Local {stormName} Tracker Hourly Daily Radar MinuteCast® Monthly Air Quality Health & Activities

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Winter Center
Today Hourly

Daily

 Radar MinuteCast® Monthly Air Quality Health & Activities
Heat Warning

August 10 - September 23

Sun 8/10

91° /70°
1%
Clear
alerts

Heat Warning

3:32 PM Sunday - 9:00 AM Wednesday

RealFeel®69°

Cloud Cover7%

WindS 7 mph

Wind Gusts15 mph

Mon 8/11

92° /71°
1%
Hot with plenty of sunshine; caution advised if doing strenuous activities outside
alerts

Heat Warning

3:32 PM Sunday - 9:00 AM Wednesday

RealFeel®97°

RealFeel Shade™91°

Max UV Index8 (Very High)

WindSSW 9 mph

Tue 8/12

93° /70°
3%
Mostly cloudy and hot; caution advised if doing strenuous activities outside
alerts

Heat Warning

3:32 PM Sunday - 9:00 AM Wednesday

RealFeel®95°

RealFeel Shade™92°

Max UV Index6 (High)

WindSSW 10 mph

Wed 8/13

85° /67°
55%
Not as hot but humid with clouds and breaks of sun; a thunderstorm in spots in the afternoon
alerts

Heat Warning

3:32 PM Sunday - 9:00 AM Wednesday

RealFeel®89°

RealFeel Shade™86°

Max UV Index7 (High)

WindWSW 8 mph

Thu 8/14

83° /62°
1%
Less humid with plenty of sunshine

RealFeel®90°

RealFeel Shade™80°

Max UV Index8 (Very High)

WindN 6 mph

Fri 8/15

84° /67°
1%
Sunshine

RealFeel®91°

RealFeel Shade™82°

Max UV Index8 (Very High)

WindNE 5 mph

Sat 8/16

88° /71°
1%
Mostly sunny and very warm

RealFeel®97°

RealFeel Shade™88°

Max UV Index8 (Very High)

WindWSW 4 mph

Sun 8/17

88° /70°
65%
Partly sunny and very warm; a thunderstorm or two in the afternoon

RealFeel®94°

RealFeel Shade™89°

Max UV Index7 (High)

WindWNW 4 mph

Mon 8/18

84° /64°
9%
Partly sunny and humid

RealFeel®97°

RealFeel Shade™91°

Max UV Index7 (High)

WindNNW 4 mph

Tue 8/19

79° /62°
61%
Times of clouds and sun with a couple of thunderstorms in the afternoon

RealFeel®86°

RealFeel Shade™79°

Max UV Index7 (High)

WindNNW 4 mph

Wed 8/20

80° /64°
1%
Partly sunny

RealFeel®81°

RealFeel Shade™77°

Max UV Index7 (High)

WindNNE 12 mph

Thu 8/21

81° /62°
1%
Mostly sunny

RealFeel®81°

RealFeel Shade™78°

Max UV Index7 (High)

WindNE 14 mph

Fri 8/22

79° /63°
0%
Plenty of sunshine

RealFeel®81°

RealFeel Shade™78°

Max UV Index7 (High)

WindN 9 mph

Sat 8/23

80° /59°
10%
Mostly sunny

RealFeel®87°

RealFeel Shade™79°

Max UV Index7 (High)

WindSSW 2 mph

Sun 8/24

79° /63°
10%
Mostly sunny

RealFeel®87°

RealFeel Shade™78°

Max UV Index7 (High)

WindS 4 mph

Mon 8/25

82° /64°
25%
Humid with considerable cloudiness

RealFeel®87°

RealFeel Shade™84°

Max UV Index2 (Low)

WindSW 2 mph

Tue 8/26

81° /65°
70%
Periods of rain in the morning; otherwise, mainly cloudy and humid

RealFeel®86°

RealFeel Shade™86°

Max UV Index3 (Moderate)

WindSSW 7 mph

Wed 8/27

80° /64°
65%
Considerable cloudiness and humid; a couple of afternoon showers and a thunderstorm

RealFeel®81°

RealFeel Shade™81°

Max UV Index2 (Low)

WindSW 12 mph

Thu 8/28

79° /63°
59%
A passing morning shower; otherwise, humid with times of clouds and sun

RealFeel®78°

RealFeel Shade™77°

Max UV Index5 (Moderate)

WindNNE 8 mph

Fri 8/29

75° /62°
20%
Partly sunny

RealFeel®81°

RealFeel Shade™72°

Max UV Index6 (High)

WindENE 5 mph

Sat 8/30

76° /61°
20%
Partly sunny

RealFeel®82°

RealFeel Shade™77°

Max UV Index6 (High)

WindSE 5 mph

Sun 8/31

81° /64°
65%
A couple of morning showers; otherwise, mostly cloudy and humid

RealFeel®85°

RealFeel Shade™84°

Max UV Index2 (Low)

WindSE 6 mph

Mon 9/1

80° /64°
55%
A passing shower in the morning; otherwise, humid with times of clouds and sun

RealFeel®87°

RealFeel Shade™85°

Max UV Index4 (Moderate)

WindESE 4 mph

Tue 9/2

80° /62°
55%
Mostly cloudy with a touch of rain

RealFeel®78°

RealFeel Shade™78°

Max UV Index2 (Low)

WindNNE 13 mph

Wed 9/3

73° /60°
20%
Turning cloudy

RealFeel®75°

RealFeel Shade™71°

Max UV Index6 (High)

WindSE 6 mph

Thu 9/4

78° /63°
64%
A couple of morning showers and a thunderstorm; otherwise, cloudy and humid

RealFeel®82°

RealFeel Shade™82°

Max UV Index1 (Low)

WindWSW 7 mph

Fri 9/5

79° /62°
25%
Cloudy and humid

RealFeel®80°

RealFeel Shade™80°

Max UV Index2 (Low)

WindNNE 5 mph

Sat 9/6

79° /62°
20%
Mostly sunny and humid

RealFeel®84°

RealFeel Shade™78°

Max UV Index6 (High)

WindNNE 6 mph

Sun 9/7

78° /61°
25%
Mostly sunny and humid

RealFeel®84°

RealFeel Shade™78°

Max UV Index6 (High)

WindNE 6 mph

Mon 9/8

79° /62°
40%
Humid with variable cloudiness; a thunderstorm in spots in the afternoon

RealFeel®81°

RealFeel Shade™81°

Max UV Index3 (Moderate)

WindNNE 5 mph

Tue 9/9

79° /61°
20%
Sunny to partly cloudy and humid

RealFeel®86°

RealFeel Shade™79°

Max UV Index5 (Moderate)

WindWNW 5 mph

Wed 9/10

78° /61°
61%
Humid with increasing cloudiness; a couple of showers and a thunderstorm in the afternoon

RealFeel®79°

RealFeel Shade™76°

Max UV Index5 (Moderate)

WindSSW 10 mph

Thu 9/11

79° /60°
20%
Mostly sunny and less humid

RealFeel®78°

RealFeel Shade™76°

Max UV Index5 (Moderate)

WindNNW 12 mph

Fri 9/12

79° /56°
40%
Partly sunny with a thunderstorm in spots in the afternoon

RealFeel®81°

RealFeel Shade™78°

Max UV Index5 (Moderate)

WindWNW 7 mph

Sat 9/13

73° /57°
1%
Mostly sunny and less humid

RealFeel®75°

RealFeel Shade™71°

Max UV Index5 (Moderate)

WindN 6 mph

Sun 9/14

69° /61°
57%
Mostly cloudy; a little morning rain followed by a shower in spots in the afternoon

RealFeel®67°

RealFeel Shade™67°

Max UV Index2 (Low)

WindENE 6 mph

Mon 9/15

69° /45°
59%
Showery in the morning; otherwise, mostly cloudy

RealFeel®67°

RealFeel Shade™67°

Max UV Index1 (Low)

WindWNW 15 mph

Tue 9/16

65° /48°
1%
Intervals of clouds and sunshine

RealFeel®64°

RealFeel Shade™64°

Max UV Index4 (Moderate)

WindWNW 12 mph

Wed 9/17

67° /49°
1%
Sunny much of the time

RealFeel®68°

RealFeel Shade™66°

Max UV Index5 (Moderate)

WindSW 7 mph

Thu 9/18

68° /52°
11%
Mostly cloudy

RealFeel®68°

RealFeel Shade™68°

Max UV Index2 (Low)

WindWSW 4 mph

Fri 9/19

73° /50°
57%
Partly sunny with a couple of showers in the afternoon

RealFeel®71°

RealFeel Shade™69°

Max UV Index5 (Moderate)

WindSSE 12 mph

Sat 9/20

68° /57°
1%
Partly sunny

RealFeel®68°

RealFeel Shade™67°

Max UV Index5 (Moderate)

WindW 9 mph

Sun 9/21

71° /47°
57%
Mostly cloudy with occasional rain in the afternoon

RealFeel®72°

RealFeel Shade™69°

Max UV Index5 (Moderate)

WindSSW 6 mph

Mon 9/22

78° /47°
0%
Mostly sunny

RealFeel®78°

RealFeel Shade™75°

Max UV Index5 (Moderate)

WindSW 7 mph

Tue 9/23

69° /57°
1%
Times of sun and clouds

RealFeel®68°

RealFeel Shade™67°

Max UV Index3 (Moderate)

WindN 10 mph

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World North America Canada Ontario St. Catharines

Weather Near St. Catharines:

  • Brampton, Ontario
  • Mississauga Valley, Ontario
  • Toronto, Ontario
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iPhone App Android App See all Apps & Downloads
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AccuWeather Premium AccuWeather Professional
More
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