Ontario, CA Weather Forecast
Local 7-day forecast
Mostly Sunny
Track current conditions, temperature changes, wind, and the full daily outlook for Ontario, CA in one place.
Mostly sunny, with a high near 76. Southwest wind 0 to 15 mph, with gusts as high as 25 mph.
Local Weather Overview
This forecast page for Ontario, CA is designed for quick trip planning, giving you a clean read on daytime highs, overnight lows, and changing conditions across the upcoming forecast window. Latest sync: May 23, 2026 11:07 PM PDT.
The active forecast window currently covers May 25 to May 30, 2026 for Ontario, CA.
Page Snapshot
- Page focus
- city weather
- Forecast window
- May 25 to May 30, 2026
- Latest sync
- May 23, 2026 11:07 PM PDT
- Forecast office
- SGX
- Source
- NOAA / NWS
Daily Outlook
This Week in Ontario
Saturday looks like the warmest upcoming period in Ontario at 82 degrees F.
Wednesday Night is the coolest period ahead with temperatures near 53 degrees F.
The strongest winds are forecast for Memorial Day at about 0 to 15 mph SW.
The forecast from May 25 through May 30 stays mostly dry.
Forecast Details
- Last updated
- May 23, 2026 11:07 PM PDT
- Coverage
- 6 days
- Time zone
- America/Los_Angeles
- Forecast office
- SGX
- Radar station
- KSOX
Weather data is provided by the National Weather Service and refreshed automatically for U.S. locations.
Open NOAA sourceExtended Forecast
Mostly cloudy, with a low around 54. Southwest wind 0 to 15 mph, with gusts as high as 25 mph.
Partly sunny, with a high near 71.
Partly cloudy, with a low around 54.
Mostly sunny, with a high near 69.
Partly cloudy, with a low around 53.
Mostly sunny, with a high near 71.
Mostly clear, with a low around 53.
Sunny, with a high near 76.
Mostly clear, with a low around 55.
Sunny, with a high near 82.
Detailed Forecast
| Period | Conditions | Temp | Wind |
|---|---|---|---|
|
Memorial Day
May 25
|
Mostly Sunny
|
76°F |
0 to 15 mph
SW
|
|
Monday Night
May 25
|
Mostly Cloudy
|
54°F |
0 to 15 mph
SW
|
|
Tuesday
May 26
|
Partly Sunny
|
71°F |
5 to 10 mph
SW
|
|
Tuesday Night
May 26
|
Partly Cloudy
|
54°F |
5 to 10 mph
SW
|
|
Wednesday
May 27
|
Mostly Sunny
|
69°F |
5 to 10 mph
S
|
|
Wednesday Night
May 27
|
Partly Cloudy
|
53°F |
0 to 10 mph
SW
|
|
Thursday
May 28
|
Mostly Sunny
|
71°F |
0 to 10 mph
SW
|
|
Thursday Night
May 28
|
Mostly Clear
|
53°F |
0 to 10 mph
SW
|
|
Friday
May 29
|
Sunny
|
76°F |
0 to 10 mph
SW
|
|
Friday Night
May 29
|
Mostly Clear
|
55°F |
0 to 10 mph
W
|
|
Saturday
May 30
|
Sunny
|
82°F |
0 to 10 mph
SW
|
Nearby Forecasts
Explore weather pages for nearby cities and major places around Ontario.
