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Ontario, California weather

United States · America/Los_Angeles · 34.06, -117.65

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Ontario, California hourly forecast

Every hour our forecast source publishes for Ontario, California — 48 hours ahead, free, with no account and no subscription. Temperature, feels like, rain chance and amount, wind and gusts, humidity, cloud cover.

Today at a glance

  • Warmest hour: 2 PM at 85°F
  • Coolest hour: 11 PM at 70°F
  • Strongest wind: 5 PM near 11 mph
  • No hour on this day has a rain chance above 50%.

Source updated: 4:21:54 PM · WeatherSignal checked: 4:21:54 PM

Source: Open-Meteo (national weather-service models)

Hour by hour

All times shown in America/Los_Angeles. Pick a day to see its hours.

Hourly weather forecast for Ontario, California
TimeConditionTempFeelsPrecip %AmountWindHumidityCloud
9 AMPartly cloudy75°74°0%0.00″3 mph WNW43%88%
10 AMMainly clear79°78°0%0.00″4 mph SW29%38%
11 AMOvercast82°81°0%0.00″4 mph SSW24%87%
12 PMOvercast82°81°0%0.00″5 mph SSW23%97%
1 PMPartly cloudy83°82°0%0.00″6 mph SW21%57%
2 PMPartly cloudy85°84°0%0.00″7 mph WSW19%84%
3 PMOvercast84°83°0%0.00″5 mph SW19%94%
4 PMOvercast84°83°0%0.00″8 mph S19%100%
5 PMOvercast81°80°0%0.00″11 mph SE20%100%
6 PMOvercast78°77°0%0.00″10 mph ESE21%100%
7 PMOvercast76°75°0%0.00″7 mph ESE25%100%
8 PMOvercast74°73°0%0.00″4 mph ENE30%99%
9 PMOvercast72°71°0%0.00″3 mph NE33%90%
10 PMOvercast71°70°0%0.00″3 mph NNE38%95%
11 PMOvercast70°69°0%0.00″3 mph NNE40%100%

What this forecast is built from

  • Source: MET Norway Locationforecast (backup source)
  • How far it goes: 48 hours (2.0 days), one value per 60 minutes
  • The primary forecast source was unavailable, so this location is running on the backup source, which publishes a shorter hourly horizon.
  • Columns are hidden when the source does not publish that measurement for this location, rather than showing an invented number.

Hourly timing is the least certain part of any forecast, and days six through eight are far less certain than tomorrow. Rain can arrive earlier or later than the hour shown. Official warnings always take precedence.

Planning your week in Ontario, California

  • The warmest afternoon ahead is tomorrow, reaching about 85°F.
  • The coldest night ahead dips to about 55°F.
  • This is a dry stretch — most days show rain chances under 20%, good for outdoor plans.
  • UV reaches 6 on the sunniest day — sunscreen is worth it if you will be outside around midday.

Common questions about Ontario, California weather

How accurate is the Ontario, California forecast?
The next 48 hours are usually reliable on temperature and sky cover, with timing that can shift by an hour or two. Days three and four are dependable for the overall pattern. Beyond that, treat the numbers as a planning direction rather than a promise — we label confidence on every day so you can judge for yourself.
When will it rain in Ontario, California?
No day in the current outlook has a rain chance above 40%, so conditions look favorable for outdoor plans across the week.
Where does this forecast come from?
Forecast values come from national weather model data, and official warnings come from the National Weather Service. We show the source and the last-updated time on every page, and we never invent a number the source did not publish — missing measurements are hidden, not guessed.
How often is this page updated?
The forecast refreshes whenever the source model publishes new data, typically several times a day. The freshness note near the top of the page shows exactly when the numbers you are looking at were issued.

More weather for Ontario, California

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