- Latitude: 34.1
- Longitude: -117.25
High Temperatures
On March 18 in this location the average high temperature is 70.9 °F (21.6 °C). The lowest recored high temperature was 46.0 °F (7.8 °C) in 1982 and the highest recored high temperature was 91.9 °F (33.3 °C) in 2004. The high temperature is usually* between 64.8 °F (18.2 °C) and 77.0 °F (25.0 °C). About a quarter of the time, the high temperature is less than 64.8 °F (18.2 °C), and another quarter of the time, the high temperature is greater than and 77.0 °F (25.0 °C). About 95% of the time, the high temperature has been between 53.3 °F (11.8 °C) and 88.6 °F (31.4 °C).
Low Temperatures
On March 18 in this location the average low temperature is 45.0 °F (7.2 °C). The lowest recored low temperature was 30.9 °F (-0.6 °C) in 2021 and the lowest recored low temperature was 69.3 °F (20.7 °C) in 1934. The low temperature is usually* between 41.4 °F (5.2 °C) and 48.6 °F (9.2 °C). About a quarter of the time, the low temperature is less than 41.4 °F (5.2 °C), and another quarter of the time, the low temperature is greater than and 48.6 °F (9.2 °C). About 95% of the time, the low temperature has been between 34.6 °F (1.4 °C) and 55.5 °F (13.0 °C).
Frost
On March 18 in this location expect the temperatures to drop below freezing for a risk of frost about 0.7% 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
- NORTON AAF — Weather Bureau Army Navy (WBAN): 23122 — from year 2015 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
- SAN BERNARDINO INTL — Integrated Surface Dataset (ISD) station ID: 722866 — from year 2009 to 2025
- SAN BERNARDINO INTERNATIONAL — Integrated Surface Dataset (ISD) station ID: 722866 — Weather Bureau Army Navy (WBAN): 23122 — from year 1943 to 2014
- RIVERSIDE MUNI — Integrated Surface Dataset (ISD) station ID: 722869 — 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 2001
- BEAUMONT — Integrated Surface Dataset (ISD) station ID: 722867 — from year 2000 to 2001
- ONTARIO — Integrated Surface Dataset (ISD) station ID: 722865 — Weather Bureau Army Navy (WBAN): 93180 — from year 1943 to 1999
- BEAUMONT — Integrated Surface Dataset (ISD) station ID: 722867 — Weather Bureau Army Navy (WBAN): 23156 — from year 1973 to 1999
- ONTARIO INTERNATIONAL ARPT — Weather Bureau Army Navy (WBAN): 03102 — from year 1968 to 1972
- BEAUMONT 1 E — Weather Bureau Army Navy (WBAN): 23156 — from year 1948 to 1953