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Saint John River

Saint John River Current Water Temperature and Forecast

On this page, you will find comprehensive information about the water temperature in Saint John River, including current readings, historical data and trends, monthly averages, as well as weather forecasts and upcoming temperature predictions. We find every spot where you can swim and tell you what the water temperature is there today and throughout the year.

Current Water Temperature in Saint John River

47°F

TODAY

46°F

YESTERDAY

40°F

A WEEK AGO

As of today, the minimum water temperature in the Saint John River ranges from 41°F (5°C) to 47°F (8°C). This water temperature is still quite low, and swimming in such conditions may only be comfortable for hardened individuals. It is recommended to limit the time spent in the water to avoid hypothermia. For those not accustomed to cold water, it is better to refrain from swimming. However, if you decide to enter the water, it is advisable to wear a warm wetsuit for protection against the cold.

It is important to note that these swimming tips and recommendations apply only in good weather. When the air temperature is below 68°F (20°C), and sometimes even below 77°F (25°C), swimming can be unpleasant even with relatively high water temperatures.

Analysis, Historical Data, and Forecast of Water Temperature

Water Temperature Chart for Saint John River Over the Last 30 Days

Today the water temperature in Saint John River is lower than the same day in previous years. The water temperature range here in May is from 41°F to 70°F. The water temperature is trending upward, and it has increased both over the past 30 days and the past week.

The forecasted water temperature values for Saint John River are presented in the table below.

The actual water temperature values near the shore may differ by a few degrees from the stated values. For the development of the forecast, we use our own mathematical model that takes into account the current water temperature changes, historical data, and key weather trends, including wind strength and direction, and air temperature in each specific region.

Daily Water Temperature Chart

DateCurrentAverageForecast
May 240°F55°F
May 344°F55°F
May 444°F55°F
May 545°F55°F
May 644°F55°F
May 744°F55°F
May 846°F55°F
May 947°F55°F
May 1055°F47°F
May 1155°F48°F
May 1255°F48°F
May 1355°F49°F
May 1455°F49°F
May 1555°F49°F
May 1655°F50°F
May 1755°F50°F
* Current - Actual water temperature value
** Average - Average water temperature on this day in recent years
*** Forecast - Our water temperature forecast

Water Temperature Ranges in Saint John River by Month

January

MinimumAverageMaximum
36°F42°F48°F

February

MinimumAverageMaximum
36°F42°F48°F

March

MinimumAverageMaximum
37°F44°F52°F

April

MinimumAverageMaximum
37°F49°F61°F

May

MinimumAverageMaximum
41°F55°F70°F

June

MinimumAverageMaximum
57°F65°F72°F

July

MinimumAverageMaximum
63°F68°F75°F

August

MinimumAverageMaximum
63°F71°F73°F

September

MinimumAverageMaximum
52°F64°F66°F

October

MinimumAverageMaximum
46°F56°F61°F

November

MinimumAverageMaximum
37°F47°F61°F

December

MinimumAverageMaximum
37°F40°F46°F

Monthly Water Temperature Histogram for Saint John River

Water Temperature in Cities and Towns on Saint John River

Canada (New Brunswick)
49°F
Canada (Maine)
44°F
Madawaska
United States (Maine)
43°F

Saint John River Weather

MAY 10

43°F / 54°F
moderate rain

rain: 89% | wind: 11 mph

MAY 11

41°F / 54°F
slight rain

rain: 87% | wind: 22 mph

MAY 12

36°F / 59°F
light drizzle

rain: 15% | wind: 17 mph

MAY 13

41°F / 70°F
overcast

rain: 15% | wind: 9 mph

MAY 14

46°F / 79°F
overcast

rain: 8% | wind: 12 mph

MAY 15

59°F / 68°F
overcast

rain: 23% | wind: 14 mph

Water Temperature in Saint John River: General Trends and Swimming Opportunities

Source Saint John Ponds
• location Somerset County, Maine, United States
Mouth Bay of Fundy
• location Saint John, New Brunswick, Canada
Length 673 km (418 mi)

The Saint John River, flowing through both the United States and Canada, provides a beautiful and relatively tranquil setting for outdoor activities, including swimming. The water temperature in the river varies depending on the season and location, but in the warmer months of summer, it typically ranges between 60°F to 75°F (15°C to 24°C), offering comfortable swimming conditions. During the cooler months, the temperature can drop significantly, especially in the northern sections of the river near New Brunswick, making swimming less inviting.

Swimming opportunities along the Saint John River are available in various regions, particularly near cities like Fredericton and Saint John in Canada, as well as the areas closer to the U.S. border. In these places, locals and visitors alike enjoy the river's calm stretches, which make it suitable for swimming. While the water is generally clean and safe, swimmers should be cautious of the river's varying currents, especially near the dam areas and after heavy rainfall. Overall, the Saint John River, with its scenic views and moderate water temperatures during the summer, is a popular spot for swimming and other water-based activities, offering a peaceful experience in nature.

Geographical Location of Saint John River

Frequently Asked Questions About Saint John River and its Water Temperatures

What is the current water temperature in Saint John River?

The water temperature today in Saint John River ranges from 43°F (6.1°C) to 49°F (9.6°C).

What is the water temperature in Saint John River during the summer months?

The average water temperature in Saint John River during the summer months is typically between 65°F to 71°F (19°C to 21°C), and it can reach up to 75°F (24°C) at its warmest. However, in some years, the temperature may exceed this range.

What is the water temperature in Saint John River in May?

The average water temperature in Saint John River in May ranges from 46°F to 70°F (8°C to 21°C).

What is the water temperature in Saint John River in September?

The average water temperature in Saint John River in September is typically between 52°F to 66°F (11°C to 19°C).

Where does Saint John River flow?

Saint John River flows through United States (Maine), Canada (New Brunswick, Quebec).

Is it possible to swim in the Saint John River?

Yes, it is possible to swim in the Saint John River. However, it's essential to consider water safety rules and local guidelines regarding water quality and currents.

What major cities are located on Saint John River?

Cities along the course of Saint John River include Edmundston (New Brunswick), Fredericton (New Brunswick).