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St. Marys, Ontario

62°F
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St. Marys, 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

August 8 - September 21

Fri 8/8

84° /66°
25%
Partly sunny, warm and humid; smoke from wildfires in Canada can create reduced air quality

RealFeel®89°

RealFeel Shade™82°

Max UV Index8 (Very High)

WindS 9 mph

Sat 8/9

87° /68°
5%
Mostly sunny, very warm and humid

RealFeel®91°

RealFeel Shade™85°

Max UV Index8 (Very High)

WindSSW 10 mph

Sun 8/10

88° /68°
1%
Mostly sunny and very warm

RealFeel®94°

RealFeel Shade™87°

Max UV Index8 (Very High)

WindSSW 9 mph

Mon 8/11

87° /68°
41%
Partly sunny and remaining very warm; a stray thunderstorm in the afternoon

RealFeel®93°

RealFeel Shade™86°

Max UV Index8 (Very High)

WindSSW 9 mph

Tue 8/12

81° /62°
90%
Overcast and humid with a couple of thunderstorms, especially late in the day

RealFeel®88°

RealFeel Shade™82°

Max UV Index5 (Moderate)

WindWSW 7 mph

Wed 8/13

82° /62°
40%
Mostly cloudy, warm and humid with a stray thunderstorm

RealFeel®86°

RealFeel Shade™83°

Max UV Index2 (Low)

WindWSW 5 mph

Thu 8/14

85° /63°
55%
Periods of clouds and sunshine with a thunderstorm in spots; warm and humid

RealFeel®92°

RealFeel Shade™87°

Max UV Index7 (High)

WindWSW 6 mph

Fri 8/15

86° /64°
74%
Considerable cloudiness with thunderstorms, especially early; very warm and humid

RealFeel®91°

RealFeel Shade™89°

Max UV Index2 (Low)

WindSSW 6 mph

Sat 8/16

86° /61°
63%
Cloudy most of the time with a couple of thunderstorms; very warm and humid

RealFeel®93°

RealFeel Shade™91°

Max UV Index6 (High)

WindSW 9 mph

Sun 8/17

84° /60°
55%
Rather cloudy, warm and humid with a little rain

RealFeel®92°

RealFeel Shade™88°

Max UV Index4 (Moderate)

WindWNW 8 mph

Mon 8/18

83° /61°
0%
Sunny, warm and humid

RealFeel®90°

RealFeel Shade™86°

Max UV Index7 (High)

WindNW 6 mph

Tue 8/19

82° /58°
3%
Partly sunny, humid and remaining warm

RealFeel®93°

RealFeel Shade™88°

Max UV Index7 (High)

WindNW 2 mph

Wed 8/20

78° /57°
2%
Humid with times of clouds and sun

RealFeel®87°

RealFeel Shade™84°

Max UV Index7 (High)

WindSSE 6 mph

Thu 8/21

79° /52°
25%
Mostly cloudy and humid

RealFeel®87°

RealFeel Shade™84°

Max UV Index3 (Moderate)

WindNNE 8 mph

Fri 8/22

75° /56°
5%
Less humid with plenty of sunshine

RealFeel®77°

RealFeel Shade™73°

Max UV Index7 (High)

WindNNE 7 mph

Sat 8/23

74° /53°
20%
Mostly sunny

RealFeel®80°

RealFeel Shade™73°

Max UV Index7 (High)

WindESE 4 mph

Sun 8/24

76° /56°
10%
Sunny

RealFeel®81°

RealFeel Shade™74°

Max UV Index7 (High)

WindSSE 4 mph

Mon 8/25

78° /57°
20%
Clouds to start, then sunshine returns

RealFeel®83°

RealFeel Shade™76°

Max UV Index7 (High)

WindSSE 4 mph

Tue 8/26

78° /58°
40%
Mainly cloudy and humid; a thunderstorm in spots in the afternoon

RealFeel®81°

RealFeel Shade™79°

Max UV Index3 (Moderate)

WindSSW 7 mph

Wed 8/27

77° /57°
57%
Humid; a little rain in the morning followed by a thunderstorm in the afternoon

RealFeel®78°

RealFeel Shade™78°

Max UV Index3 (Moderate)

WindSW 8 mph

Thu 8/28

75° /56°
25%
After a cloudy start, sun returns

RealFeel®76°

RealFeel Shade™72°

Max UV Index7 (High)

WindNNE 7 mph

Fri 8/29

73° /55°
5%
Less humid with plenty of sunshine

RealFeel®76°

RealFeel Shade™71°

Max UV Index6 (High)

WindENE 6 mph

Sat 8/30

74° /56°
25%
Times of clouds and sun

RealFeel®73°

RealFeel Shade™73°

Max UV Index4 (Moderate)

WindESE 7 mph

Sun 8/31

77° /57°
55%
Mostly cloudy and humid with a bit of rain

RealFeel®78°

RealFeel Shade™78°

Max UV Index3 (Moderate)

WindESE 6 mph

Mon 9/1

77° /57°
25%
Mostly cloudy and humid

RealFeel®80°

RealFeel Shade™80°

Max UV Index2 (Low)

WindNE 5 mph

Tue 9/2

76° /55°
25%
Mostly cloudy, seasonably warm and less humid

RealFeel®75°

RealFeel Shade™74°

Max UV Index4 (Moderate)

WindNNE 8 mph

Wed 9/3

73° /55°
25%
Turning cloudy

RealFeel®71°

RealFeel Shade™71°

Max UV Index3 (Moderate)

WindSE 8 mph

Thu 9/4

76° /54°
25%
Cloudy and humid

RealFeel®77°

RealFeel Shade™77°

Max UV Index2 (Low)

WindW 6 mph

Fri 9/5

75° /55°
25%
Less humid with considerable cloudiness

RealFeel®75°

RealFeel Shade™75°

Max UV Index2 (Low)

WindNNE 5 mph

Sat 9/6

75° /55°
10%
Abundant sunshine

RealFeel®75°

RealFeel Shade™72°

Max UV Index6 (High)

WindNE 7 mph

Sun 9/7

76° /54°
20%
Mostly sunny and warm

RealFeel®77°

RealFeel Shade™73°

Max UV Index6 (High)

WindNE 5 mph

Mon 9/8

75° /55°
25%
Cloudy and warm

RealFeel®75°

RealFeel Shade™75°

Max UV Index1 (Low)

WindNNE 4 mph

Tue 9/9

75° /54°
25%
Clouds limiting sun

RealFeel®75°

RealFeel Shade™75°

Max UV Index3 (Moderate)

WindESE 2 mph

Wed 9/10

74° /54°
59%
Partly sunny with a thunderstorm in the afternoon

RealFeel®76°

RealFeel Shade™73°

Max UV Index5 (Moderate)

WindSW 8 mph

Thu 9/11

74° /53°
20%
Partly sunny and less humid

RealFeel®74°

RealFeel Shade™71°

Max UV Index5 (Moderate)

WindNNW 8 mph

Fri 9/12

76° /52°
57%
Partly sunny; a thunderstorm in spots in the morning followed by a couple of showers in the afternoon

RealFeel®76°

RealFeel Shade™73°

Max UV Index5 (Moderate)

WindWNW 9 mph

Sat 9/13

71° /52°
1%
Mostly sunny

RealFeel®75°

RealFeel Shade™69°

Max UV Index5 (Moderate)

WindNNE 4 mph

Sun 9/14

70° /54°
55%
A couple of morning showers; otherwise, mostly cloudy

RealFeel®68°

RealFeel Shade™68°

Max UV Index2 (Low)

WindNE 6 mph

Mon 9/15

68° /38°
57%
A couple of morning showers; otherwise, mostly cloudy

RealFeel®66°

RealFeel Shade™64°

Max UV Index2 (Low)

WindWNW 17 mph

Tue 9/16

60° /41°
1%
Intervals of clouds and sunshine

RealFeel®59°

RealFeel Shade™59°

Max UV Index2 (Low)

WindNW 10 mph

Wed 9/17

62° /45°
1%
Sunny much of the time

RealFeel®62°

RealFeel Shade™61°

Max UV Index5 (Moderate)

WindSW 9 mph

Thu 9/18

66° /46°
13%
Mostly cloudy

RealFeel®68°

RealFeel Shade™66°

Max UV Index2 (Low)

WindW 2 mph

Fri 9/19

72° /45°
65%
Partly sunny with a couple of showers and a thunderstorm in the afternoon

RealFeel®70°

RealFeel Shade™68°

Max UV Index5 (Moderate)

WindS 13 mph

Sat 9/20

63° /50°
2%
Partly sunny

RealFeel®63°

RealFeel Shade™63°

Max UV Index5 (Moderate)

WindW 9 mph

Sun 9/21

66° /39°
59%
Periods of rain

RealFeel®64°

RealFeel Shade™63°

Max UV Index5 (Moderate)

WindSSW 9 mph

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World North America Canada Ontario St. Marys

Weather Near St. Marys:

  • Brampton, Ontario
  • Mississauga Valley, Ontario
  • Toronto, Ontario
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Apps & Downloads
iPhone App Android App See all Apps & Downloads
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AccuWeather Premium AccuWeather Professional
More
AccuWeather Ready Business Health Hurricane Leisure and Recreation Severe Weather Space and Astronomy Sports Travel Weather News Winter Center
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