- Latitude: 33.898
- Longitude: -117.602
High Temperatures
On April 21 in this location the average high temperature is 74.9 °F (23.8 °C). The lowest recored high temperature was 53.1 °F (11.7 °C) in 1957 and the highest recored high temperature was 100.9 °F (38.3 °C) in 2009. The high temperature is usually* between 68.9 °F (20.5 °C) and 80.9 °F (27.2 °C). About a quarter of the time, the high temperature is less than 68.9 °F (20.5 °C), and another quarter of the time, the high temperature is greater than and 80.9 °F (27.2 °C). About 95% of the time, the high temperature has been between 57.4 °F (14.1 °C) and 92.4 °F (33.5 °C).
Low Temperatures
On April 21 in this location the average low temperature is 50.1 °F (10.0 °C). The lowest recored low temperature was 34.9 °F (1.6 °C) in 1973 and the lowest recored low temperature was 73.0 °F (22.8 °C) in 1987. The low temperature is usually* between 46.8 °F (8.2 °C) and 53.3 °F (11.9 °C). About a quarter of the time, the low temperature is less than 46.8 °F (8.2 °C), and another quarter of the time, the low temperature is greater than and 53.3 °F (11.9 °C). About 95% of the time, the low temperature has been between 40.6 °F (4.8 °C) and 59.6 °F (15.3 °C).
Frost
On April 21 in this location expect the temperatures to drop below freezing for a risk of frost about 0.0% of the time.
Data Source(s)
The data used to compute the average high/low temperatures for this location were taken from the following stations:
- MARCH AIR RESERVE BASE — Integrated Surface Dataset (ISD) station ID: 722860 — Weather Bureau Army Navy (WBAN): 23119 — from year 1933 to 2025
- ONTARIO INTERNATIONAL ARPT — Integrated Surface Dataset (ISD) station ID: 747040 — Weather Bureau Army Navy (WBAN): 03102 — from year 2005 to 2025
- RIVERSIDE MUNICIPAL ARPT — Integrated Surface Dataset (ISD) station ID: 722869 — Weather Bureau Army Navy (WBAN): 03171 — from year 2006 to 2025
- CHINO AIRPORT — Integrated Surface Dataset (ISD) station ID: 722899 — Weather Bureau Army Navy (WBAN): 03179 — from year 2006 to 2025
- FULLERTON MUNICIPAL ARPT — Integrated Surface Dataset (ISD) station ID: 722976 — Weather Bureau Army Navy (WBAN): 03166 — from year 2006 to 2025
- CORONA MUNICIPAL AIRPORT — Integrated Surface Dataset (ISD) station ID: 720333 — Weather Bureau Army Navy (WBAN): 53175 — from year 2011 to 2025
- BRACKETT FIELD AIRPORT — Integrated Surface Dataset (ISD) station ID: 722887 — Weather Bureau Army Navy (WBAN): 03180 — from year 2013 to 2025
- CABLE — Integrated Surface Dataset (ISD) station ID: 720329 — from year 2018 to 2025
- CORONA MUNI — Integrated Surface Dataset (ISD) station ID: 720333 — from year 2007 to 2017
- RIVERSIDE MUNI — Integrated Surface Dataset (ISD) station ID: 722869 — from year 1999 to 2005
- CHINO — Integrated Surface Dataset (ISD) station ID: 722899 — from year 1999 to 2005
- RIVERSIDE/MARCH AFB — Integrated Surface Dataset (ISD) station ID: 722860 — from year 2000 to 2004
- ONTARIO INTL ARPT — Integrated Surface Dataset (ISD) station ID: 747040 — from year 2002 to 2004
- ONTARIO — Integrated Surface Dataset (ISD) station ID: 722865 — from year 2000 to 2000
- ONTARIO — Integrated Surface Dataset (ISD) station ID: 722865 — Weather Bureau Army Navy (WBAN): 93180 — from year 1943 to 1999
- EL TORO MCAS — Integrated Surface Dataset (ISD) station ID: 690140 — Weather Bureau Army Navy (WBAN): 93101 — from year 1989 to 1999
- FOB DWYER — Integrated Surface Dataset (ISD) station ID: 690160 — Weather Bureau Army Navy (WBAN): 93114 — from year 1990 to 1998
- TUSTIN MCAF — Integrated Surface Dataset (ISD) station ID: 722915 — Weather Bureau Army Navy (WBAN): 93114 — from year 1976 to 1989
- EL TORO MCAS — Weather Bureau Army Navy (WBAN): 93101 — from year 1945 to 1988
- EL TORO(USMC) — Integrated Surface Dataset (ISD) station ID: 722908 — from year 1973 to 1988
- MARINE CORPS AIR STATION — Weather Bureau Army Navy (WBAN): 93114 — from year 1945 to 1975
- ONTARIO INTERNATIONAL ARPT — Weather Bureau Army Navy (WBAN): 03102 — from year 1968 to 1972