ClimateForecastNovemberDecember >>

Saint Helens (OR) Climate by Month

The temperature in Saint Helens can vary greatly throughout the year. The temperatures shift from warm to cold. It also has a notably wet climate with much precipitation. Now, let’s break down all the climate details for a clearer picture.

Average day and night temperature

Depending on the time of the year, temperatures range from comfortable to chilly in Saint Helens. Average daytime temperatures range from a comfortable 28°C in August, the warmest time of the year, to a chilly 7°C during cooler months like December. At night, temperatures typically average around 1°C during these months.

The mean minimum and maximum temperatures throughout the year

Precipitation and rainy days

Saint Helens has a relatively rain/snowy climate with high precipitation levels, averaging 1096 mm of rain/snowfall annually. Significant seasonal changes in precipitation occur throughout the year. During the wetter season, December receives heavy rainfall, averaging 198 mm of precipitation, recorded across 22 rainy days. In contrast, the drier season, July brings less rainfall, with 12 mm over 4 rainy days.

The mean monthly precipitation over the year, including rain, hail and snow

Sunshine over the year

Seasonal changes in sunshine hours are quite dramatic in Saint Helens. While July receives considerable daily sunshine with up to 11.1 hours, December marks the darkest time of the year, where sunshine is scarce with only 2.1 hours of sunlight per day.

Monthly hours of sunshine

Data from: Portland, the United States of America (33 KM, 20 Miles).

Daily hours of sunshine

Data from: Portland, the United States of America (33 KM, 20 Miles).

The best time of year to visit Saint Helens in the United States of America

During the months of May, June and September you are most likely to experience good weather with pleasant average temperatures that fall between 20°C and 26°C.

Other facts from our historical weather data:
  • Which months have the greatest rainfall in Saint Helens?
    Most rainfall (rainy season) is seen in January, November and December.
  • Does Saint Helens have a dry season?
    Yes, the months of July and August are very dry.
  • Which is the warmest month in Saint Helens?
    August has an average maximum temperature of 28°C and is the warmest month of the year.
  • Which is the coldest month in Saint Helens?
    The coldest month is December with an average maximum temperature of 7°C.
  • Which is the wettest month in Saint Helens?
    December tops the wettest month list with 198 mm of rainfall.
  • Which is the driest month in Saint Helens?
    July is the driest month with 12 mm of precipitation.
  • Which is the sunniest month in Saint Helens?
    July is the sunniest month with an average of 332 hours of sunshine.

  • No idea where to travel to this year? We have a tool that recommends destinations based on your ideal conditions. Find out where to go with our weather planner.

    Forecast for Saint Helens (OR)

    Thu   Nov 21
    11°C | 6°C
    SE 7 km/h
    1.2 mm
    partly cloudy and rain

    partly cloudy and rain

    Fri   Nov 22
    13°C | 6°C
    S 18 km/h
    16 mm
    broken clouds and rain

    broken clouds and rain

    Sat   Nov 23
    9°C | 5°C
    S 11 km/h
    3.9 mm
    overcast and rain

    overcast and rain