- Latitude: 33.952
- Longitude: -117.439
High Temperatures
On September 18 in this location the average high temperature is 87.8 °F (31.0 °C). The lowest recored high temperature was 66.9 °F (19.4 °C) in 1963 and the highest recored high temperature was 107.1 °F (41.7 °C) in 2016. The high temperature is usually* between 82.3 °F (27.9 °C) and 93.4 °F (34.1 °C). About a quarter of the time, the high temperature is less than 82.3 °F (27.9 °C), and another quarter of the time, the high temperature is greater than and 93.4 °F (34.1 °C). About 95% of the time, the high temperature has been between 71.6 °F (22.0 °C) and 104.0 °F (40.0 °C).
Low Temperatures
On September 18 in this location the average low temperature is 59.1 °F (15.0 °C). The lowest recored low temperature was 41.9 °F (5.5 °C) in 2006 and the lowest recored low temperature was 78.3 °F (25.7 °C) in 1934. The low temperature is usually* between 55.5 °F (13.1 °C) and 62.6 °F (17.0 °C). About a quarter of the time, the low temperature is less than 55.5 °F (13.1 °C), and another quarter of the time, the low temperature is greater than and 62.6 °F (17.0 °C). About 95% of the time, the low temperature has been between 48.8 °F (9.3 °C) and 69.3 °F (20.7 °C).
Frost
On September 18 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 2024
- NORTON AAF — Weather Bureau Army Navy (WBAN): 23122 — from year 2014 to 2024
- ONTARIO INTERNATIONAL ARPT — Integrated Surface Dataset (ISD) station ID: 747040 — Weather Bureau Army Navy (WBAN): 03102 — from year 2005 to 2024
- RIVERSIDE MUNICIPAL ARPT — Integrated Surface Dataset (ISD) station ID: 722869 — Weather Bureau Army Navy (WBAN): 03171 — from year 2006 to 2024
- CHINO AIRPORT — Integrated Surface Dataset (ISD) station ID: 722899 — Weather Bureau Army Navy (WBAN): 03179 — from year 2006 to 2024
- SAN BERNARDINO INTL — Integrated Surface Dataset (ISD) station ID: 722866 — from year 2009 to 2024
- CORONA MUNICIPAL AIRPORT — Integrated Surface Dataset (ISD) station ID: 720333 — Weather Bureau Army Navy (WBAN): 53175 — from year 2011 to 2024
- CABLE — Integrated Surface Dataset (ISD) station ID: 720329 — from year 2018 to 2024
- CORONA MUNI — Integrated Surface Dataset (ISD) station ID: 720333 — from year 2006 to 2017
- SAN BERNARDINO INTERNATIONAL — Integrated Surface Dataset (ISD) station ID: 722866 — Weather Bureau Army Navy (WBAN): 23122 — from year 1943 to 2013
- RIVERSIDE MUNI — Integrated Surface Dataset (ISD) station ID: 722869 — from year 1998 to 2005
- CHINO — Integrated Surface Dataset (ISD) station ID: 722899 — from year 1998 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 2001 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
- ONTARIO INTERNATIONAL ARPT — Weather Bureau Army Navy (WBAN): 03102 — from year 1968 to 1972