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 71°F across the year, from 95°F highs in July to 24°F lows in January, and December is usually the wettest month in a year that brings about 10 in of precipitation.
Warmest month
July
95°F average high
Coldest month
January
24°F average low
Wettest month
December
10 in a year
Below freezing
4 months
January, February, November and December
Comfortable
3 months
April, May and October
Residents
11,000
share this forecast
The weather map: all three models at once
NWS, American, European side by side around Ontario and nearby towns.Live rain radar →
Loading the three model maps…
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
Loading the three models…
Ontario 10-day forecast, out to 14 days
where the models agree, and where they split
Ontario, Oregon (OR) is at its warmest in Jul (average highs near 95°F) and coldest in Jan (lows around 24°F), with roughly 10 in of precipitation across the year. Below, compare what NWS, American, European forecast for Ontario right now, and see exactly where they disagree.
average daytime high and overnight low across a typical year (1991-2020)
Jan
38°
24°
Feb
45°
27°
Mar
55°
35°
Apr
63°
40°
May
73°
49°
Jun
83°
59°
Jul
95°
66°
Aug
91°
64°
Sep
79°
54°
Oct
63°
41°
Nov
46°
31°
Dec
35°
24°
Source: 1991-2020 averages, ERA5 for this place adjusted with NASA POWER.
How Ontario's weather has changed since 1995
30 years of daily data, 1995-2024, shown as change
+0.4°F
Around Ontario, the difference between 1995-2004 and 2015-2024 is +0.4°F, within the normal swing from year to year.
1995each stripe is one year2024
cooler than averagearound averagewarmer than average
Days above 95°F
7 more days a year
2015-2024 against 1995-2004. Within the normal year-to-year swing
Frost nights
1 fewer night a year
2015-2024 against 1995-2004, below 32°F. Within the normal year-to-year swing
Average wind
−2%
2015-2024 against 1995-2004. Within the normal year-to-year swing
Bars: each year against the area's 30-year average. Dashed lines: the average of the first and the last ten years.
See the numbers year by year
Year
Temp vs average
Days >95°F vs avg
Frost nights vs avg
Wind vs avg
1995
−0.9°F
−24
−19
−1%
1996
−0.9°F
−2
−5
+3%
1997
−0.6°F
−21
+11
−1%
1998
−0.2°F
+4
−12
−1%
1999
−0.8°F
−10
+7
+6%
2000
−0.4°F
−3
+8
−1%
2001
+0.7°F
+7
+7
−1%
2002
±0.0°F
−1
−2
+6%
2003
+2.1°F
+7
−8
−1%
2004
+0.5°F
−4
−6
−4%
2005
−0.2°F
+1
−2
−8%
2006
+0.1°F
+5
+3
+3%
2007
+0.9°F
+14
−10
+3%
2008
−1.1°F
−4
+15
+6%
2009
−1.5°F
−4
+21
−1%
2010
−1.3°F
−16
+16
+3%
2011
−2.0°F
−12
+27
−1%
2012
+1.2°F
+6
−0
+3%
2013
−0.6°F
+18
+15
−1%
2014
+1.4°F
+2
−19
−1%
2015
+1.9°F
−4
−17
−4%
2016
+0.5°F
−9
−21
+3%
2017
−1.1°F
+5
−9
−4%
2018
+0.3°F
−1
−3
+3%
2019
−0.8°F
−4
−3
−1%
2020
+0.3°F
−6
+6
−4%
2021
+1.6°F
+20
+2
+6%
2022
−0.6°F
+20
+22
−4%
2023
+0.1°F
−3
+12
−4%
2024
+1.2°F
+5
−21
−4%
Source: NASA POWER daily data from the MERRA-2 reanalysis, 1995-2024. Each value describes a grid square of about 50 km around Ontario, not a weather station, and a square that takes in sea or a large lake runs milder than the city itself. That is why this section shows change against the square's own 30-year average rather than counts you could compare with a local station. Rain and snow are left out because their long-term record in this dataset is not consistent over time. "Within the normal year-to-year swing" means the change is smaller than the usual differences between single years.
Which forecast is most accurate in the US?
CheckWeather Score, graded against the weather that actually happened
Provider
CheckWeather-score
Temp
Wind
Rain
Run by
European ★ Best
93
/100rank #1
91±0.9°F
97±1.1 mph
9396% hit
ECMWF - European Centre for Medium-Range Weather ForecastsReading, United Kingdom
American
82
/100rank #2
83±1.7°F
94±2.0 mph
7184% hit
NOAA / NCEP (United States)College Park, Maryland, USA
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)
Loading ratings…
AmericanNOAA GFS
Loading ratings…
EuropeanECMWF
Loading ratings…
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.
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?
No single model is always right. NWS, American, European each run their own physics, so we line all three up: when they agree the Ontario forecast is reliable, and when they split you should expect surprises. See our tested US accuracy scoreboard for how the models compare.
What is the warmest month in Ontario?
July is typically the warmest month in Ontario, with average highs around 95°F.
How cold does Ontario get?
The coldest month in Ontario is January, when overnight lows average about 24°F.
How much rain does Ontario get?
Ontario sees roughly 10 in of precipitation a year, with December usually the wettest month.
Is Ontario getting warmer?
Not clearly. In NASA's reanalysis for the area around Ontario, the difference between 1995-2004 and 2015-2024 is 0.4°F, within the normal swing from year to year.
