2025 Compare Climate & Weather:
Sisters, OR vs Ontario, OR

Highlights

On average, there are 207 sunny days per year in Ontario. Sisters averages 162 sunny days per year. The US average is 205 sunny days.

Ontario, Oregon gets 10.6 inches of rain, on average, per year. Sisters, Oregon gets 11.4 inches of rain, on average, per year. The US average is 38.1 inches of rain per year.

Ontario averages 13.2 inches of snow per year. Sisters averages 16.1 inches of snow per year. The US average is 27.8 inches of snow per year.

Weather Highlights

Ontario, Oregon
Summer High: the July high is around 91.9 degrees
Winter Low: the January low is 20.3
Rain: averages 10.6 inches of rain a year
Snow: averages 13.2 inches of snow a year

Sisters, Oregon
Summer High: the July high is around 84.2 degrees
Winter Low: the January low is 23.2
Rain: averages 11.4 inches of rain a year
Snow: averages 16.1 inches of snow a year

BestPlaces Comfort Index

The annual BestPlaces Comfort Index for Ontario is 7.2 (10=best), which means it is about average compared to other places in Oregon.

The annual BestPlaces Comfort Index for Sisters is 7.0 (10=best), which means it is less comfortable than most places in Oregon.

Today's Weather - Sisters, OR

47°F

Today's Weather - Ontario, OR

61°F

Average Monthly High / Low (°F)

Hot, Freezing, Rainy, Snowy Days: Sisters / Ontario

July is the hottest month for Sisters with an average high temperature of 84.2°, which ranks it as warmer than most places in Oregon. In Sisters, there are 4 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Sisters are September, June and August.

July is the hottest month for Ontario with an average high temperature of 91.9°, which ranks it as one of the hottest places in Oregon. In Ontario, there are 3 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Ontario are September, June and May.

December has the coldest nighttime temperatures for Sisters with an average of 21.4°. This is colder than most places in Oregon.

January has the coldest nighttime temperatures for Ontario with an average of 20.3°. This is one of the coldest places in Oregon.

In Sisters, there are 19.7 days annually when the high temperature is over 90°, which is hotter than most places in Oregon.

In Ontario, there are 50.9 days annually when the high temperature is over 90°, which is one of the hottest places in Oregon.

In Sisters, there are 178.7 days annually when the nighttime low temperature falls below freezing, which is one of the coldest places in Oregon.

In Ontario, there are 137.4 days annually when the nighttime low temperature falls below freezing, which is colder than most places in Oregon.

In Sisters, there are 2.8 days annually when the nighttime low temperature falls below zero°, which is colder than most places in Oregon.

In Ontario, there are 4.0 days annually when the nighttime low temperature falls below zero°, which is one of the coldest places in Oregon.

January is the wettest month in Sisters with 1.6 inches of rain, and the driest month is August with 0.4 inches. The wettest season is Spring with 37% of yearly precipitation and 15% occurs in Autumn, which is the driest season. The annual rainfall of 11.4 inches in Sisters means that it is one of the driest places in Oregon.


December is the wettest month in Ontario with 1.7 inches of rain, and the driest month is August with 0.2 inches. The wettest season is Spring with 37% of yearly precipitation and 12% occurs in Autumn, which is the driest season. The annual rainfall of 10.6 inches in Ontario means that it is one of the driest places in Oregon.

December is the rainiest month in Sisters with 9.1 days of rain, and August is the driest month with only 2.7 rainy days. There are 72.8 rainy days annually in Sisters, which is one of the least rainy places in Oregon. The rainiest season is Spring when it rains 34% of the time and the driest is Autumn with only a 15% chance of a rainy day.

December is the rainiest month in Ontario with 10.3 days of rain, and July is the driest month with only 2.3 rainy days. There are 78.5 rainy days annually in Ontario, which is one of the least rainy places in Oregon. The rainiest season is Spring when it rains 35% of the time and the driest is Autumn with only a 12% chance of a rainy day.

An annual snowfall of 16.1 inches in Sisters means that it is snowier than most places in Oregon.

An annual snowfall of 13.2 inches in Ontario means that it is snowier than most places in Oregon.

December is the snowiest month in Sisters with 4.8 inches of snow, and 5 months of the year have significant snowfall.

December is the snowiest month in Ontario with 6.5 inches of snow, and 4 months of the year have significant snowfall.