2025 Compare Climate & Weather:
Prosser, WA vs Mount Vernon, WA

Highlights

On average, there are 156 sunny days per year in Mount Vernon. Prosser averages 190 sunny days per year. The US average is 205 sunny days.

Mount Vernon, Washington gets 38.1 inches of rain, on average, per year. Prosser, Washington gets 8.5 inches of rain, on average, per year. The US average is 38.1 inches of rain per year.

Mount Vernon averages 5 inches of snow per year. Prosser averages 5.8 inches of snow per year. The US average is 27.8 inches of snow per year.

Weather Highlights

Mount Vernon, Washington
Summer High: the July high is around 72.8 degrees
Winter Low: the January low is 35.7
Rain: averages 38.1 inches of rain a year
Snow: averages 5 inches of snow a year

Prosser, Washington
Summer High: the July high is around 89.3 degrees
Winter Low: the January low is 27.2
Rain: averages 8.5 inches of rain a year
Snow: averages 5.8 inches of snow a year

BestPlaces Comfort Index

The annual BestPlaces Comfort Index for Mount Vernon is 7.2 (10=best), which means it is more comfortable than most places in Washington.

The annual BestPlaces Comfort Index for Prosser is 7.6 (10=best), which means it is one of the most pleasant places in Washington.

Today's Weather - Prosser, WA

66°F

Today's Weather - Mount Vernon, WA

56°F

Average Monthly High / Low (°F)

Hot, Freezing, Rainy, Snowy Days: Prosser / Mount Vernon

July is the hottest month for Prosser with an average high temperature of 89.3°, which ranks it as one of the hottest places in Washington. In Prosser, there are 3 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Prosser are September, June and May.

August is the hottest month for Mount Vernon with an average high temperature of 73.8°, which ranks it as cooler than most places in Washington. In Mount Vernon, there are 2 comfortable months with high temperatures in the range of 70-85°. The most pleasant months of the year for Mount Vernon are August, July and September.

December has the coldest nighttime temperatures for Prosser with an average of 25.7°. This is colder than most places in Washington.

December has the coldest nighttime temperatures for Mount Vernon with an average of 34.6°. This is warmer than most places in Washington.

In Prosser, there are 37.7 days annually when the high temperature is over 90°, which is one of the hottest places in Washington.

In Mount Vernon, there are 0.2 days annually when the high temperature is over 90°, which is one of the coolest places in Washington.

In Prosser, there are 97.9 days annually when the nighttime low temperature falls below freezing, which is colder than most places in Washington.

In Mount Vernon, there are 38.9 days annually when the nighttime low temperature falls below freezing, which is warmer than most places in Washington.

In Prosser, there are 0.7 days annually when the nighttime low temperature falls below zero°, which is colder than most places in Washington.

In Mount Vernon, there are 0.0 days annually when the nighttime low temperature falls below zero°, which is about average compared to other places in Washington.

December is the wettest month in Prosser with 1.3 inches of rain, and the driest month is July with 0.2 inches. The wettest season is Spring with 38% of yearly precipitation and 13% occurs in Autumn, which is the driest season. The annual rainfall of 8.5 inches in Prosser means that it is one of the driest places in Washington.


November is the wettest month in Mount Vernon with 6.0 inches of rain, and the driest month is July with 1.3 inches. The wettest season is Spring with 31% of yearly precipitation and 13% occurs in Autumn, which is the driest season. The annual rainfall of 38.1 inches in Mount Vernon means that it is about average compared to other places in Washington.

December is the rainiest month in Prosser with 9.3 days of rain, and July is the driest month with only 2.0 rainy days. There are 67.5 rainy days annually in Prosser, which is one of the least rainy places in Washington. The rainiest season is Spring when it rains 36% of the time and the driest is Autumn with only a 12% chance of a rainy day.

November is the rainiest month in Mount Vernon with 20.0 days of rain, and August is the driest month with only 5.6 rainy days. There are 165.0 rainy days annually in Mount Vernon, which is rainier than most places in Washington. The rainiest season is Spring when it rains 32% of the time and the driest is Autumn with only a 14% chance of a rainy day.

An annual snowfall of 5.8 inches in Prosser means that it is about average compared to other places in Washington.

An annual snowfall of 5.0 inches in Mount Vernon means that it is about average compared to other places in Washington.

December is the snowiest month in Prosser with 3.6 inches of snow, and 3 months of the year have significant snowfall.

December is the snowiest month in Mount Vernon with 2.0 inches of snow, and 4 months of the year have significant snowfall.