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Ontario Running Weather

Thursday, June 4, 2026 · Hour-by-hour forecast updated 3:49 AM PDT

Best Time to Run in Ontario Today

5 AM–8 AM

57°F and clear at peak. Wind 4 mph from the WNW, dew point 56°F.

87
Peak FitScore
Temperature
57°F / feels 57°
Wind
4 mph WNW, gusts 7
Dew Point
56°F — noticeable
Humidity
96%
UV Index
0 — Low
Air Quality
69 AQI — Moderate

Hourly running conditions

🌙 5 AM
87
57° feels 57° 4 mph WNW
🌅 6 AM
87
56° feels 57° 3 mph WNW
🌤️ 7 AM
84
59° feels 61° 1 mph WNW
☀️ 8 AM
83
63° feels 65° 1 mph WSW
☀️ 9 AM
74
69° feels 71° 2 mph WSW
☀️ 10 AM
62
76° feels 79° 3 mph SW
☀️ 11 AM
49
82° feels 86° 5 mph WSW
☀️ 12 PM
48
88° feels 91° 7 mph W
☀️ 1 PM
47
90° feels 92° 9 mph W
☀️ 2 PM
46
91° feels 92° 11 mph W
☀️ 3 PM
42
90° feels 90° 13 mph W
☀️ 4 PM
41
88° feels 87° 13 mph W
80–100 Excellent 60–79 Good 40–59 Fair Below 40 Poor

7-day running forecast

🌤️
Today Jun 4
91° / 56°
87
🏃 5 AM–8 AM
🌫️
Fri Jun 5
88° / 59°
87
🏃 5 AM–8 AM
☁️
Sat Jun 6
84° / 66°
84
🏃 9 AM–12 PM
☀️
Sun Jun 7
83° / 63°
88
🏃 9 AM–12 PM
☀️
Mon Jun 8
86° / 64°
85
🏃 6–9 AM
☀️
Tue Jun 9
83° / 64°
86
🏃 9 AM–12 PM
☁️
Wed Jun 10
80° / 64°
90
🏃 9 AM–12 PM
Get Ontario's forecast every evening

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FitCast
iMessage
🌤 Tomorrow in Ontario: Best window: 9–11 AM (FitScore 95) 6am: 48°F, feels 45° — NW 8mph 9am: 58°F, feels 56° — W 12mph 12pm: 66°F, feels 65° — SW 8mph ☔ Rain likely after 3pm.
Yesterday 8:14 PM Nightly

Ontario running weather FAQ

What's the best time to run in Ontario today?

Based on today's FitScore analysis, the best time to run is 5 AM–8 AM with a peak FitScore of 87/100. Check the hourly breakdown above for detailed conditions throughout the day.

What months are best for running in Ontario?

The best months for running in Ontario are June, July, August, September. The most challenging months are typically November, December. Mild summers with low humidity make for ideal running. Watch for marine layer fog in coastal areas.

What is the FitScore?

FitScore rates each hour from 0–100 for outdoor exercise based on temperature, humidity, dew point, wind, precipitation probability, UV index, and air quality. Higher scores mean better conditions.

Nearby:Pomona, CAFontana, CACorona, CA
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