Climate and monthly weather forecastOntario, OR
Climate and monthly weather forecast
Weather in January
January, like December, in Ontario, Oregon, is a wintry winter month, with an average temperature fluctuating between 23.5°F (-4.7°C) and 36.1°F (2.3°C). Ontario's coldest period falls in January and December, when the average high-temperatures ascend to 36.1°F (2.3°C). Weather in January »Weather in February
The last month of the winter, February, is another cold month in Ontario, Oregon, with an average temperature fluctuating between 42.4°F (5.8°C) and 29.1°F (-1.6°C). February's onset brings a subtle temperature rise, moving from a cold 36.1°F (2.3°C) in January to a still icy 42.4°F (5.8°C). Weather in February »Weather in March
The first month of the spring, March, is a fresh month in Ontario, Oregon, with temperature in the range of an average low of 36.9°F (2.7°C) and an average high of 53.2°F (11.8°C). The arrival of March brings an increase in high-temperatures, moving from a cold 42.4°F (5.8°C) in February to a fresh 53.2°F (11.8°C). Weather in March »Weather in April
April in Ontario, Oregon, is a refreshing spring month, with an average temperature fluctuating between 40.3°F (4.6°C) and 62.2°F (16.8°C). In Ontario, stepping into April brings a temperature increase, moving up from March's cool 53.2°F (11.8°C) to a refreshing 62.2°F (16.8°C). Weather in April »Weather in May
The last month of the spring, May, is an agreeable month in Ontario, Oregon, with an average temperature ranging between max 72.1°F (22.3°C) and min 46.9°F (8.3°C). May's arrival sees a rise in the average high-temperature, jumping from April's comfortable 62.2°F (16.8°C) to an agreeable 72.1°F (22.3°C). Weather in May »Weather in June
June, the first month of the summer in Ontario, is a warm month, with an average temperature fluctuating between 54.1°F (12.3°C) and 81°F (27.2°C). With the onset of June, Ontario observes a minor temperature ascent, with the average high-temperature adjusting from May's pleasant 72.1°F (22.3°C) to a warm 81°F (27.2°C). Weather in June »Weather in July
July in Ontario, Oregon, is a hot summer month, with temperature in the range of an average high of 93.2°F (34°C) and an average low of 62.2°F (16.8°C). Ontario's warmest month, July, generally records average temperatures ranging from a high of 93.2°F (34°C) to a low of 62.2°F (16.8°C). Weather in July »Weather in August
The last month of the summer, August, is another tropical month in Ontario, Oregon, with an average temperature varying between 91.9°F (33.3°C) and 62.1°F (16.7°C). Ontario indicates an average high-temperature of a still tropical 91.9°F (33.3°C) in August, showing minor variation from July's 93.2°F (34°C). Weather in August »Weather in September
The first month of the autumn, September, is also a moderately hot month in Ontario, Oregon, with an average temperature varying between 80.6°F (27°C) and 55.2°F (12.9°C). September's onset brings a slight change in high-temperatures, falling from a tropical 91.9°F (33.3°C) in August to a warm 80.6°F (27°C). Weather in September »Weather in October
October, the same as September, is another refreshing autumn month in Ontario, Oregon, with an average temperature ranging between min 43.7°F (6.5°C) and max 62.6°F (17°C). October's onset witnesses a marked shift in the average high-temperature, moving from a warm 80.6°F (27°C) in September to a refreshing 62.6°F (17°C). Weather in October »Weather in November
The last month of the autumn, November, is also a frosty month in Ontario, Oregon, with an average temperature varying between 32.7°F (0.4°C) and 48.2°F (9°C). With the beginning of November, Ontario's average high-temperature experiences a significant decrease, moving from a refreshing 62.6°F (17°C) in October to a frosty 48.2°F (9°C). Weather in November »Weather in December
The first month of the winter, December, is also a wintry month in Ontario, Oregon, with an average temperature ranging between min 23°F (-5°C) and max 36.1°F (2.3°C). During January and December, Ontario registers its lowest temperatures, averaging a high of 36.1°F (2.3°C). Weather in December »Updated: Jun 4, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Ontario experiences the lowest of its temperatures in January and December, when the average high-temperatures rise to 36.1°F (2.3°C).
January is the most humid month in Ontario, with an average relative humidity of 82%.
Throughout the year, in Ontario, Oregon, there are 84.9 rainfall days, and 9.29" (236mm) of precipitation is accumulated.
Months with snowfall are January through April, November and December.
In Ontario, during the entire year, snow falls for 21.8 days and aggregates up to 12.56" (319mm) of snow.
January, February, November and December, with an average maximum UV index of 2, are months with the lowest UV index.
On Sunday, March 10. 2024, at 2:00 am, Daylight Saving Time starts, and the time zone changes from MST to MDT. Daylight Saving Time ends Sunday, November 3. 2024, at 2:00 am, and the time zone reverts from MDT to MST.
In Ontario, snow does not fall in May through October.
June has the longest days of the year, with an average of 15h and 24min of daylight.
In Ontario, the average temperatures in July are the highest, with a peak at 93.2°F (34°C) and a low of 62.2°F (16.8°C).
July is the month with the least rainfall. Rain falls for 2.5 days and accumulates 0.08" (2mm) of precipitation.
With an average of 12.1h of sunshine, July has the most sunshine of the year.
With an average maximum UV index of 7, July is the month with the highest UV index.
The least humid month is August, with an average relative humidity of 29%.
December is the month with the most rainfall. Rain falls for 8.9 days and accumulates 1.57" (40mm) of precipitation.
The month with the most snowfall is December, when snow falls for 7.4 days and typically aggregates up to 5.35" (136mm) of snow.
The month with the shortest days is December, with an average of 9h and 0min of daylight.
With an average of 5.1h of sunshine, December has the least sunshine of the year.
Average temperature
Ontario, OR
The warmest month (with the highest average high temperature) is July (93.2°F).
The months with the lowest average high temperature are January and December (36.1°F).
The month with the highest average low temperature is July (62.2°F).
The coldest month (with the lowest average low temperature) is December (23°F).
Average pressure
Ontario, OR
- Average pressure in January:
30.24"Hg - Average pressure in February:
30.12"Hg - Average pressure in March:
30.04"Hg - Average pressure in April:
30"Hg - Average pressure in May:
29.94"Hg - Average pressure in June:
29.92"Hg
- Average pressure in July:
29.93"Hg - Average pressure in August:
29.92"Hg - Average pressure in September:
29.96"Hg - Average pressure in October:
30.05"Hg - Average pressure in November:
30.13"Hg - Average pressure in December:
30.21"Hg
The month with the highest atmospheric pressure is January (30.24"Hg).
The months with the lowest atmospheric pressure are June and August (29.92"Hg).
Average wind speed
Ontario, OR
- Average wind speed in January:
3.9mph - Average wind speed in February:
4.9mph - Average wind speed in March:
6mph - Average wind speed in April:
6.5mph - Average wind speed in May:
6.1mph - Average wind speed in June:
6.1mph
- Average wind speed in July:
5.8mph - Average wind speed in August:
5.3mph - Average wind speed in September:
5.2mph - Average wind speed in October:
4.7mph - Average wind speed in November:
4.7mph - Average wind speed in December:
4.3mph
The windiest month (with the highest average wind speed) is April (6.5mph).
The calmest month (with the lowest average wind speed) is January (3.9mph).
Average humidity
Ontario, OR
The month with the highest relative humidity is January (82%).
The month with the lowest relative humidity is August (29%).
Average rainfall
Ontario, OR
- Average rainfall in January:
1.42" - Average rainfall in February:
1.14" - Average rainfall in March:
1.38" - Average rainfall in April:
0.71" - Average rainfall in May:
0.83" - Average rainfall in June:
0.51"
- Average rainfall in July:
0.08" - Average rainfall in August:
0.12" - Average rainfall in September:
0.2" - Average rainfall in October:
0.59" - Average rainfall in November:
0.75" - Average rainfall in December:
1.57"
The wettest month (with the highest rainfall) is December (1.57").
The driest month (with the least rainfall) is July (0.08").
Average rainfall days
Ontario, OR
- Average rainfall days in January:
9.3 days - Average rainfall days in February:
8.8 days - Average rainfall days in March:
13.3 days - Average rainfall days in April:
9.7 days - Average rainfall days in May:
7.8 days - Average rainfall days in June:
5.8 days
- Average rainfall days in July:
2.5 days - Average rainfall days in August:
1.8 days - Average rainfall days in September:
3.1 days - Average rainfall days in October:
6.6 days - Average rainfall days in November:
7.3 days - Average rainfall days in December:
8.9 days
The month with the highest number of rainy days is March (13.3 days).
The month with the least rainy days is August (1.8 days).
Average snowfall
Ontario, OR
The month with the highest snowfall is December (5.35").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days
Ontario, OR
- Average snowfall days in January:
6.3 days - Average snowfall days in February:
5.2 days - Average snowfall days in March:
1.3 days - Average snowfall days in April:
0.1 days - Average snowfall days in May:
0 days - Average snowfall days in June:
0 days
- Average snowfall days in July:
0 days - Average snowfall days in August:
0 days - Average snowfall days in September:
0 days - Average snowfall days in October:
0 days - Average snowfall days in November:
1.5 days - Average snowfall days in December:
7.4 days
The month with the highest number of snowfall days is December (7.4 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight / Average sunshine
Ontario, OR
- Average daylight in January:
9h and 18min - Average daylight in February:
10h and 30min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 30min - Average daylight in May:
14h and 48min - Average daylight in June:
15h and 24min
- Average daylight in July:
15h and 6min - Average daylight in August:
13h and 54min - Average daylight in September:
12h and 30min - Average daylight in October:
11h and 0min - Average daylight in November:
9h and 36min - Average daylight in December:
9h and 0min
The month with the longest days is June (Average daylight: 15h and 24min).
The month with the shortest days is December (Average daylight: 9h and 0min).
- Average sunshine in January:
5h and 12min - Average sunshine in February:
7h and 24min - Average sunshine in March:
8h and 6min - Average sunshine in April:
9h and 36min - Average sunshine in May:
11h and 18min - Average sunshine in June:
11h and 36min
- Average sunshine in July:
12h and 6min - Average sunshine in August:
11h and 12min - Average sunshine in September:
9h and 30min - Average sunshine in October:
8h and 6min - Average sunshine in November:
6h and 30min - Average sunshine in December:
5h and 6min
The month with the most sunshine is July (Average sunshine: 12h and 6min).
The month with the least sunshine is December (Average sunshine: 5h and 6min).
Average sunshine days
Ontario, OR
- Average sunshine days in January:
17.8 days - Average sunshine days in February:
15.2 days - Average sunshine days in March:
15.9 days - Average sunshine days in April:
18.8 days - Average sunshine days in May:
21.3 days - Average sunshine days in June:
22.9 days
- Average sunshine days in July:
27.7 days - Average sunshine days in August:
27.3 days - Average sunshine days in September:
26.1 days - Average sunshine days in October:
23.4 days - Average sunshine days in November:
20.7 days - Average sunshine days in December:
17.3 days
The month with the most sunshine days is July (27.7 days).
The month with the least sunshine days is February (15.2 days).
Average UV index
Ontario, OR
The month with the highest UV index is July (UV index 7).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover
Ontario, OR
The months with the most cloud cover are January and December (Cloud cover 44).
The month with the least cloud cover is July (Cloud cover 8).
Average visibility
Ontario, OR
The months with the highest visibility are February, March, April, May, June, July, August, September, October and November (6mi).
The months with the lowest visibility are January and December (5mi).
