River in Quebec

St. Lawrence River Weather Forecast

St. Lawrence River weather: 37°F, clear. Hourly forecast, 14-day outlook, UV, air quality and the best time to visit.

🌙 37°F now🕔 7:27 PM local📅 Best: September

Summary

St. Lawrence River is a river in Quebec. St. Lawrence River is a river known as the Great Lakes outlet to the Atlantic.

Right now it is 37°F (3°C) in St. Lawrence River with clear. It feels like 31°F. Today runs from 27°F to 51°F. Chance of precipitation is 0%. Sightseeing conditions score 7.6/10 - good conditions.

The best time to visit St. Lawrence River is September. The climate is subarctic. January, March and December tend to be the least comfortable months. July is the warmest month with average highs near 78°F, while February is the coldest with lows near 4°F.

The closest major airport is Montreal-Trudeau International Airport (YUL), about 153 mi away. Nearby highlights include Baxter State Park, Mont-Tremblant National Park, Mount Washington and Franconia Notch State Park.

In plain terms. Today is slightly cooler than average for October. The forecast high of 51°F is 5.9°F below the 57°F typical for this month. The best window to be outside is roughly 2 PM to 5 PM, when temperature, rain chance and wind line up best. stargazing is the strongest bet in St. Lawrence River today at 10/10. Overnight lows near 27°F mean ice is possible on bridges before dawn.

Compiled from this page's own data: atlas facts plus live Open-Meteo readings.

Active alerts for St. Lawrence River

⚠️Sat, Oct 24: freezing overnight, 27°F (-3°C). Expect ice on roads and trails.
⚠️Sun, Oct 25: freezing overnight, 32°F (-0°C). Expect ice on roads and trails.
⚠️Mon, Nov 2: heavy rain, 1,1 in. Flooding and delays possible.

Derived from the forecast. No official alert feed is wired for this country yet.

Weather in St. Lawrence River right now

🌙
37°F
Clear · feels like 31°F
Humidity80%
Wind5 mph SSW
Gusts9 mph
UV index0 · Low
Cloud cover0%
Pressure1025 hPa
VisibilityGood · 8 mi
Air quality54 · Moderate
Sunrise7:15 AM
Sunset5:41 PM
Moon🌕 Full moon · 99%

Source: Open-Meteo. Updated 7:27 PM, Oct 25 local time.

⚠️Sat, Oct 24: freezing overnight, 27°F (-3°C). Expect ice on roads and trails.
⚠️Sun, Oct 25: freezing overnight, 32°F (-0°C). Expect ice on roads and trails.
⚠️Mon, Nov 2: heavy rain, 1,1 in. Flooding and delays possible.

Next 24 hours

Hour-by-hour temperature, precipitation chance and wind.

10 PM🌙37°0%5 mph
11 PM🌙36°0%5 mph
12 AM🌙35°0%4 mph
1 AM🌙34°0%5 mph
2 AM🌙33°0%5 mph
3 AM🌙33°0%5 mph
4 AM🌙33°0%4 mph
5 AM🌙32°0%5 mph
6 AM🌙32°0%4 mph
7 AM☀️32°0%4 mph
8 AM☀️32°0%4 mph
9 AM☁️36°0%5 mph
10 AM☁️41°0%8 mph
11 AM☁️44°0%9 mph
12 PM⛅47°0%10 mph
1 PM☀️50°0%10 mph
2 PM☀️52°0%9 mph
3 PM☀️53°0%8 mph
4 PM☀️53°0%7 mph
5 PM⛅50°0%6 mph
6 PM☁️46°0%6 mph
7 PM☁️43°0%5 mph
8 PM☁️42°0%5 mph
9 PM☁️41°2%4 mph

16-day forecast for St. Lawrence River

Daily highs and lows, precipitation and UV.

DayConditionsHigh / LowPrecipWindUV
Sat, Oct 24☁️ Overcast51° / 27°0%8 mph3
Sun, Oct 25☁️ Overcast54° / 32°4%10 mph3
Mon, Oct 26🌦️ Light drizzle54° / 39°37% · 0,0 in13 mph3
Tue, Oct 27☀️ Clear sky45° / 33°0%9 mph3
Wed, Oct 28☁️ Overcast47° / 33°0%8 mph3
Thu, Oct 29🌦️ Light drizzle55° / 36°41% · 0,0 in10 mph3
Fri, Oct 30☁️ Overcast52° / 40°40%9 mph2
Sat, Oct 31☁️ Overcast49° / 35°11%5 mph3
Sun, Nov 1🌦️ Light drizzle48° / 44°41% · 0,1 in3 mph0
Mon, Nov 2🌧️ Rain57° / 48°43% · 1,1 in7 mph0
Tue, Nov 3🌦️ Light drizzle54° / 39°38% · 0,0 in14 mph3
Wed, Nov 4☁️ Overcast47° / 34°29%8 mph3
Thu, Nov 5🌦️ Light rain46° / 39°23% · 0,6 in9 mph0
Fri, Nov 6☁️ Overcast45° / 38°21%12 mph2
Sat, Nov 7🌥️ Fog42° / 31°29%11 mph2
Sun, Nov 8🌧️ Rain41° / 37°26% · 1,0 in16 mph0

Climate in St. Lawrence River month by month

Average high, average low and total rainfall, based on three years of reanalysis data.

JanFebMarAprMayJunJulAugSepOctNovDecLine: average high · Bars: rainfall
MonthAvg highAvg lowRainfallRating
January21°5°2,7 in★★☆☆☆
February24°4°2,0 in★★☆☆☆
March34°17°4,1 in★★☆☆☆
April49°30°4,9 in★★☆☆☆
May62°44°5,0 in★★★☆☆
June73°54°6,9 in★★★☆☆
July78°61°5,1 in★★★★☆
August75°57°6,5 in★★★☆☆
September68°50°1,8 in★★★★☆
October57°42°3,5 in★★★☆☆
November38°27°3,5 in★★☆☆☆
December26°11°3,8 in★☆☆☆☆

Climate type: Subarctic. Source: Open-Meteo archive (ERA5).

Weather map for St. Lawrence River

Animated model layers. Pick a layer to load it.

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Animated layers by Windy. For pin-level detail and nearby places, see the interactive map below.

Air quality and pollen in St. Lawrence River

54
Moderate
Unusually sensitive people should limit long outdoor exertion.
PM2.512.9 µg/m³
PM1012.9 µg/m³
Ozone20 µg/m³
NO₂21.6 µg/m³
UV index0 · Low
Airborne hazeClear air

Air quality: Open-Meteo (CAMS). US AQI scale.

Sun, twilight and moon

Sunrise7:15 AM
Sunset5:41 PM
Daylight10h 26m
Solar noon12:28 PM
Golden hour (am)7:15 AM - 8:15 AM
Golden hour (pm)4:41 PM - 5:41 PM
Blue hour (am)6:45 AM - 7:15 AM
Blue hour (pm)5:41 PM - 6:11 PM
Moon phase🌕 Full moon · 99%
Moonrise4:55 PM
Moonset6:45 AM

Golden and blue hour are the standard photographic approximation around sunrise and sunset.

Best time to visit St. Lawrence River

Go in September. These months score highest on comfortable temperatures, low rainfall and useful daylight.

Hardest months: January, March and December - expect the least comfortable mix of heat, cold or rain.

January★★☆☆☆
February★★☆☆☆
March★★☆☆☆
April★★☆☆☆
May★★★☆☆
June★★★☆☆
July★★★★☆
August★★★☆☆
September★★★★☆
October★★★☆☆
November★★☆☆☆
December★☆☆☆☆

Explore St. Lawrence River

Every topic we hold for this place, and the same topic for the places around it.

Weather for related places

Frequently asked questions

Where is St. Lawrence River?

St. Lawrence River is a river in Quebec. Its coordinates are 46.8139, -71.208. It lies in North America.

What is the weather like in St. Lawrence River right now?

It is currently 37°F (3°C) with clear. Humidity is 80% and wind is 5 mph.

When is the best time to visit St. Lawrence River?

September offer the most comfortable conditions in St. Lawrence River, which has a subarctic climate. January, March and December are usually the hardest months for outdoor plans.

What time zone is St. Lawrence River in?

St. Lawrence River observes America/Toronto (UTC-04:00). The local time is 7:27 PM.

What is the nearest airport to St. Lawrence River?

The closest airports are Montreal-Trudeau International Airport (YUL), 153 mi away and Boston Logan International Airport (BOS), 308 mi away.

What are the top things to do in St. Lawrence River?

Popular options include Baxter State Park, Mont-Tremblant National Park, Mount Washington, Franconia Notch State Park and Acadia National Park.

Related articles

Data sources and methodology

Place dataUSPOTUS Atlas dataset (rivers) - coordinates, hierarchy and facts.
Forecast and observationsOpen-Meteo (ECMWF and national models).
Air quality and pollenCopernicus CAMS via Open-Meteo. US AQI scale.
Climate averagesERA5 reanalysis via the Open-Meteo archive, aggregated over 3 years.
MethodScores, comparisons and advice on this page are computed from the inputs above. Distances are straight-line. Nothing is estimated where data is missing - the block is simply not shown.

Last updated October 25, 2026 at 7:27 PM local time. Live blocks refresh every 15 minutes; climate averages monthly.

Davil Hofile
Written byWriter at USPOTUS

Davil Hofile is a writer at USPOTUS covering breaking news, NFL updates, viral stories, entertainment, pets, and lifestyle. He specializes in transforming complex news into clear, trustworthy, and engaging articles that help readers quickly understand what's happening across the United States. His reporting follows Google's E-E-A-T guidelines, emphasizing accuracy, credible sources, and practical value for readers.

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