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Ontario Running Weather

Tuesday, July 21, 2026 · Hour-by-hour forecast updated 6:24 AM PDT

Best Time to Run in Ontario Today

5 AM–7 AM

66°F and clear at peak. Wind 4 mph from the NW, dew point 54°F.

90
Peak FitScore
Temperature
66°F / feels 66°
Wind
4 mph NW, gusts 4
Dew Point
54°F — comfortable
Humidity
65%
UV Index
0 — Low
Air Quality
56 AQI — Moderate

Hourly running conditions

🌅 6 AM
82
69° feels 69° 3 mph NW 1% rain
☀️ 7 AM
72
71° feels 72° 4 mph W 1% rain
☀️ 8 AM
65
75° feels 76° 4 mph W 1% rain
☀️ 9 AM
65
79° feels 79° 4 mph WSW 1% rain
☀️ 10 AM
61
83° feels 84° 5 mph WSW 1% rain
🌤️ 11 AM
51
86° feels 88° 7 mph WSW 1% rain
☀️ 12 PM
50
89° feels 90° 9 mph WSW 1% rain
☀️ 1 PM
43
91° feels 92° 10 mph WSW 1% rain
☀️ 2 PM
39
92° feels 93° 12 mph WSW 1% rain
☀️ 3 PM
43
91° feels 91° 13 mph WSW 1% rain
☀️ 4 PM
39
90° feels 90° 13 mph W 1% rain
☀️ 5 PM
37
89° feels 87° 13 mph W 1% rain
80–100 Excellent 60–79 Good 40–59 Fair Below 40 Poor

7-day running forecast

Today Jul 21
92° / 69°
90
🏃 5 AM–7 AM
☀️
Wed Jul 22
95° / 66°
90
🏃 5 AM–7 AM
☀️
Thu Jul 23
99° / 77°
59
🏃 6–9 AM
☀️
Fri Jul 24
99° / 80°
58
🏃 6–9 AM
☀️
Sat Jul 25
101° / 79°
57
🏃 6–9 AM
☁️
Sun Jul 26
100° / 79°
58
🏃 6–9 AM
☁️
Mon Jul 27
96° / 81°
59
🏃 6–9 AM
Get Ontario's forecast every evening

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🌤 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–7 AM with a peak FitScore of 90/100. 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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