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Forecast confidence: High · models disagree by 1°F

Ontario weather

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Mostly clear,much the same tomorrow

NWS, the American and the European model agree on a high near 82° in Ontario today. Tomorrow looks cloudy around 85°, with a 0% chance of rain.

82°61°
85°60°
84°62°
80°64°
83°63°
89°66°
Todaymodels agreeTomorrowmodels agreeSundaysplit ±5°Mondaymodels agreeTuesdaymodels agreeWednesdaymodels agree
NWSNational Blend (NBM)
81°
Mostly clear
Today 81°·Low 61°·Rain 0%
AmericanNOAA GFS
83°
Cloudy
Today 83°·Low 60°·Rain 0%
EuropeanECMWF
82°
Mostly clear
Today 82°·Low 61°·Rain 0%
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Ontario weather alerts and warnings

active National Weather Service watches, warnings and advisories

Checking the National Weather Service for active alerts covering Ontario…

Ontario weather in numbers

from 30 years of measured normals

Ontario swings 51°F across the year, from 94°F highs in July to 43°F lows in February, and February is usually the wettest month in a year that brings about 32 in of precipitation.

Warmest month
July
94°F average high
Coldest month
February
43°F average low
Wettest month
February
32 in a year
Below freezing
Never
overnight lows stay above 32°F
Comfortable
4 months
January, March, April and May
Residents
171,000
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The weather map: all three models at once

NWS, American, European side by side around Ontario and nearby towns.Live rain radar →
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Ontario hourly forecast: next 14 hours

consensus of the three models

Rain in the next 24 hours, model by model

each model's own hourly precipitation, side by side

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Ontario 10-day forecast, out to 14 days

where the models agree, and where they split
Today
Mostly clear
82° 61°
models agree
Tomorrow
Cloudy
85° 60°
models agree
Sun
Partly cloudy
84° 62°
±5°
Mon
Cloudy
80° 64°
models agree
Tue
Mostly clear
83° 63°
models agree
Wed
Clear
89° 66°
models agree
Thu
Clear
88° 67°
±5°
Fri
Mostly clear
87° 69°
±14°
Sat
Mostly clear
89° 69°
±14°
Sun
Cloudy
92° 72°
±15°
Mon
Mostly clear
93° 74°
±17°
Tue
Cloudy
94° 75°
models agree
Wed
Clear
86° 67°
±4°
Thu
Clear
80° 65°
models agree

Ontario, California (CA) is at its warmest in Jul (average highs near 94°F) and coldest in Feb (lows around 43°F), with roughly 32 in of precipitation across the year. Below, compare what NWS, American, European forecast for Ontario right now, and see exactly where they disagree.

We grade every model against the weather that actually happened, so you can see which forecast model is most accurate in United States before you trust any single number.

Ontario climate by month

average daytime high and overnight low across a typical year
Jan
60°
44°
Feb
60°
43°
Mar
61°
46°
Apr
71°
49°
May
75°
53°
Jun
82°
57°
Jul
94°
65°
Aug
93°
66°
Sep
87°
63°
Oct
84°
60°
Nov
72°
49°
Dec
68°
48°

Which forecast is most accurate in Ontario?

CheckWeather Score, graded against the weather that actually happened
ProviderCheckWeather-scoreTempWindRainRun by
European logo
European ★ Best
90
/100rank #1
80±2.0°F98±0.7 mph9597% hitECMWF - European Centre for Medium-Range Weather ForecastsReading, United Kingdom
American logo
American
88
/100rank #2
87±1.3°F90±3.0 mph8994% hitNOAA / NCEP (United States)College Park, Maryland, USA

The CheckWeather Score blends temperature, wind and rain accuracy, each measured against ERA5 (the recorded weather) over the last 30 days across 1999 cities. Lower error means a higher score. See which forecast model is most accurate in United States, how we measure forecast accuracy, or which model each weather app uses.

What do you think of the forecasts?

your vote counts

The accuracy above is the measured record. This is your opinion: which forecast service do you trust most in United States? Give each 1 to 5 stars.

NWSNational Blend (NBM)
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AmericanNOAA GFS
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EuropeanECMWF
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One vote per service. Anonymous: we store no personal data, only a one-way hash of your connection for a day to stop double votes.

Where the models disagree

temperature and rain, judged separately
DayTemperatureRain
Today±1°81° to 83°models agree0% to 0% chance
Tomorrow±1°85° to 86°models agree0% to 0% chance
Sun±5°81° to 86°±2%0% to 2% chance
Mon±4°78° to 82°±4%2% to 6% chance
Tue±2°82° to 84°models agree0% to 0% chance

The models often agree on temperature and still split on rain, and rain is usually what decides whether a plan survives. A wide rain range means the shower is genuinely uncertain, not that the forecast is wrong.

Sunrise and sunset in Ontario

today, local time
Sunrise
06:35
Sunset
18:52
Daylight
12h 17m

Common questions

What's the weather in Ontario today?
On this page we show what NWS, American, European each forecast for Ontario today, side by side and updated live. When all three agree the forecast is reliable; when they split, we flag it so you know the day is genuinely less certain.
Will it rain in Ontario today or tomorrow?
Check the hourly strip and 7-day forecast above. We compare rain from NWS, American, European for Ontario and flag the days where the models disagree on whether showers actually arrive, which is exactly when a single app can catch you out.
Which forecast is most accurate for Ontario?
Over the last 30 days, the European model has been the most accurate for Ontario (CheckWeather Score 90/100), ahead of the American at 88. We grade every model against the recorded weather. See the US accuracy scoreboard for the full method.
What is the warmest month in Ontario?
July is typically the warmest month in Ontario, with average highs around 94°F.
How cold does Ontario get?
The coldest month in Ontario is February, when overnight lows average about 43°F.
How much rain does Ontario get?
Ontario sees roughly 32 in of precipitation a year, with February usually the wettest month.

Nearby

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