Climate normals · 1970–2000
Fullerton Climate
Fullerton is a city in United States (CA) with a population of about 140,847. Its average annual temperature is 18.4°C (65°F), with roughly 371 mm of rain per year.
18.4°C
Avg Temp
371
Precip (mm/yr)
Aug
Hottest Month
Dec
Coldest Month
Fullerton Climate
Fullerton has an average annual temperature of 18.4°C (65°F) and receives about 371 mm of precipitation per year. The warmest month is August and the coldest is December. Figures are 1970–2000 climate normals.
18.4°C
Avg Temp
371
Precip (mm/yr)
Aug
Hottest Month
Dec
Coldest Month
| Month | Avg (°C/°F) | Precip |
|---|---|---|
| January | 14° / 57° | 80 mm |
| February | 15° / 58° | 82 mm |
| March | 15° / 59° | 71 mm |
| April | 17° / 63° | 22 mm |
| May | 19° / 66° | 5 mm |
| June | 21° / 70° | 2 mm |
| July | 23° / 74° | 1 mm |
| August | 24° / 75° | 3 mm |
| September | 23° / 73° | 7 mm |
| October | 20° / 68° | 11 mm |
| November | 16° / 62° | 36 mm |
| December | 14° / 57° | 51 mm |
1970–2000 normals from WorldClim 2.1 (~9 km grid). Precipitation can be less precise near mountains or coastlines, where rainfall varies sharply over short distances.
Best time to visit Fullerton
The most comfortable months to visit Fullerton are typically June, October and July, when temperatures are mildest and rainfall is relatively low. The hottest month is August (around 30°C high). The coldest is December (near 7°C low). February is usually the wettest month.
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Frequently Asked Questions
The most comfortable months to visit Fullerton are typically June, October and July, when temperatures are mildest and rainfall is relatively low (1970–2000 climate normals).
Fullerton, United States has an average annual temperature of 18.4°C and about 371 mm of precipitation per year. The warmest month is August and the coldest is December.
In August, the hottest month, daily highs in Fullerton average about 30°C (86°F).
Monthly climate normals (1970–2000) sampled from WorldClim 2.1 at ~9 km resolution. Humidity derived from vapor pressure. City coordinates and population from GeoNames.