Snow in Ontario, California Winter storm alerts · 7-day snow forecast · average snowfall
Alerts for Ontario right now
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Snow forecast — next 7 days
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Measurable snow is rare in Ontario: the 1991–2020 normal rounds to zero — only a trace in most years, and nights reach freezing on about 2 days a year. When snow or ice does arrive, it causes outsized trouble because roads are rarely treated — watch for Winter Weather Advisories and Freeze Warnings.
Winter by month
Month
Snowfall
Days 1″+
Days with snow cover
Freezing nights
Avg. low
December
0″
0
0
1
44°F
January
0″
0
0
1
45°F
Year
0″
0
0
2
NOAA NCEI U.S. Climate Normals 1991–2020 — snowfall at Pomona/Fairplex (7 mi from the city center, -7 ft elevation difference); temperatures at Ontario Intl. Airport. Averages smooth out big years: single winters can bring half or double the normal.
0 inches in an average year (NOAA U.S. Climate Normals 1991–2020, Pomona/Fairplex station, 7 miles away).
Is there a winter storm warning for Ontario today?
This page checks the National Weather Service for active alerts at Ontario's location every time you open it; the box at the top lists any winter storm, winter weather, cold or freeze alert in effect right now.
How many freezing nights does Ontario have?
About 2 nights a year drop to 32 °F or below (NOAA 1991–2020); the coldest month, December, averages a low of 44 °F.