🇺🇸 Weather in Fullerton
Map Overlays:
Hourly Forecast for Fullerton
00:00
17°
25%
01:00
17°
26%
02:00
17°
26%
03:00
16°
26%
04:00
16°
27%
05:00
16°
26%
06:00
17°
18%
07:00
17°
15%
08:00
18°
19%
09:00
20°
11%
10:00
21°
1%
11:00
22°
1%
12:00
23°
1%
13:00
24°
1%
14:00
24°
2%
15:00
24°
1%
16:00
23°
1%
17:00
22°
1%
18:00
22°
1%
19:00
21°
1%
20:00
20°
3%
21:00
19°
1%
22:00
18°
2%
23:00
18°
2%
14-Day Forecast for Fullerton
2026-06-05
Overcast
29° /
17°
2026-06-06
Cloudy
24° /
16°
2026-06-07
Sunny
24° /
17°
2026-06-08
Sunny
25° /
17°
2026-06-09
Sunny
26° /
18°
2026-06-10
Sunny
26° /
18°
2026-06-11
Partly Cloudy
25° /
18°
Additional Forecasts for Fullerton
Air Quality
💨 US EPA Index 2 (Moderate)
CO (Carbon Monoxide) 124.0 μg/m³
O₃ (Ozone) 60.0 μg/m³
NO₂ (Nitrogen Dioxide) 25.3 μg/m³
SO₂ (Sulphur Dioxide) 3.8 μg/m³
PM2.5 (Fine particles) 15.7 μg/m³
PM10 (Coarse particles) 21.2 μg/m³
Historical Weather
Weather Forecasts for Other Cities in United States
Weather in Fullerton — FAQ
Answers refreshed each request based on current conditions in Fullerton.
What is the weather like right now in Fullerton?
Right now in Fullerton, United States the temperature is 18.3°C (feels like 18.3°C), with overcast. Relative humidity is 78% and wind is 9.7 km/h.
What is today's high and low temperature in Fullerton?
Today's forecast high in Fullerton is 28.6°C and the overnight low is 16.7°C. The diurnal range — high minus low — depends on cloud cover; clear days swing more than overcast ones.
Will it rain in Fullerton today?
The chance of precipitation in Fullerton today is 8%. Forecast accuracy is highest within the next 6 hours and decreases steadily out to 14 days.
How often does the weather here update?
Current observations refresh every 15-60 minutes from the nearest monitoring stations operated by national meteorological agencies. The hourly forecast updates approximately every hour; the 7- and 14-day outlook is recomputed several times per day.
What does 'feels like' temperature mean?
Feels-like (apparent) temperature accounts for humidity, wind chill and direct sunshine — variables that change how the human body perceives heat or cold. On hot, humid days it can be 3-7°C above the actual reading; on cold windy days it can be 5-15°C below.
Why does the temperature in Fullerton differ from nearby cities?
Even short distances can change temperatures noticeably. Fullerton's reading reflects altitude, proximity to large bodies of water, urban heat island effects, and the exact location of the monitoring stations supplying the data. Coastal cities are typically milder and more humid than inland equivalents.