Weather on March 21
San Mateo, CA
55 Years of Data
About This Date
March 21st in San Mateo, CA typically brings mild spring weather, with average highs around 62°F and lows near 48°F. Over 56 years of records, the warmest March 21st was in 1997 (65°F average), while the coldest was 1973 (47°F) — a 18°F range across recorded history. Rain or other precipitation has occurred on about 32% of March 21st dates historically, with the wettest March 21st recording 1.12" of rain. Temperatures on this date have remained relatively stable over the past several decades.
Temperatures on this date have remained relatively stable over the past several decades.
Planning for March 21st in San Mateo, CA? Great weather for outdoor activities. Consider bringing rain gear or an umbrella.
| Year | High | Low | Avg | Precip | Snow |
|---|---|---|---|---|---|
| 2026 | 75° | 53° | 64° | — | — |
| 2025 | 61° | 46° | 53° | — | — |
| 2024 | 67° | 52° | 59° | — | — |
| 2023 | 56° | 48° | 52° | 1.12" | — |
| 2022 | 65° | 49° | 57° | — | — |
| 2021 | 61° | 44° | 52° | — | — |
| 2020 | 62° | 47° | 54° | — | — |
| 2019 | 61° | 46° | 53° | — | — |
| 2018 | 65° | 55° | 60° | 0.13" | — |
| 2017 | 65° | 57° | 61° | 0.28" | — |
| 2016 | 64° | 54° | 59° | 0.01" | — |
| 2015 | 73° | 56° | 64° | — | — |
| 2014 | 65° | 49° | 57° | — | — |
| 2013 | 59° | 44° | 52° | — | — |
| 2012 | 67° | 49° | 58° | — | — |
| 2011 | 57° | 46° | 52° | 0.08" | — |
| 2010 | 63° | 49° | 56° | — | — |
| 2009 | 56° | 48° | 52° | 0.16" | — |
| 2008 | 63° | 43° | 53° | — | — |
| 2007 | 62° | 46° | 54° | — | — |
| 2006 | 55° | 45° | 50° | 0.02" | — |
| 2005 | 60° | 52° | 56° | 0.5" | — |
| 2004 | 64° | 53° | 59° | — | — |
| 2003 | 62° | 49° | 55° | — | — |
| 2002 | 63° | 50° | 56° | — | — |
| 2001 | 63° | 52° | 57° | — | — |
| 2000 | 71° | 53° | 62° | — | — |
| 1999 | 61° | 50° | 55° | 0.04" | — |
| 1998 | 61° | 54° | 57° | 0.1" | — |
| 1997warmest | 74° | 57° | 65° | — | — |
| 1996 | 59° | 46° | 53° | — | — |
| 1995 | 54° | 44° | 49° | 0.17" | — |
| 1994 | 61° | 48° | 54° | — | — |
| 1993 | 63° | 52° | 57° | — | — |
| 1992 | 65° | 55° | 60° | — | — |
| 1991 | 56° | 47° | 51° | 0.22" | — |
| 1990 | 63° | 47° | 55° | — | — |
| 1989 | 64° | 52° | 58° | — | — |
| 1988 | 64° | 51° | 58° | — | — |
| 1987 | 53° | 43° | 48° | 0.35" | — |
| 1986 | 64° | 50° | 57° | — | — |
| 1985 | 58° | 43° | 50° | — | — |
| 1984 | 62° | 46° | 54° | — | — |
| 1983 | 58° | 44° | 51° | — | — |
| 1982 | 58° | 42° | 50° | — | — |
| 1981 | 63° | 50° | 56° | 0.26" | — |
| 1980 | 62° | 45° | 53° | 0.03" | — |
| 1979 | 58° | 49° | 53° | — | — |
| 1978 | 67° | 52° | 59° | 0.19" | — |
| 1977 | 73° | 39° | 56° | — | — |
| 1976 | 64° | 39° | 52° | — | — |
| 1975 | 55° | 42° | 49° | 0.3" | — |
| 1974 | 60° | 47° | 53° | — | — |
| 1973coldest | 61° | 34° | 47° | 0.25" | — |
| 1972 | 65° | 43° | 54° | — | — |
| 1971 | 62° | 43° | 52° | — | — |
San Mateo, CA Temperature Range by Month
Average monthly highs and lows. The shaded band shows the typical daily temperature range.
San Mateo, CA Monthly Precipitation
Average rainfall per month, in inches.
San Mateo, CA Daily Temperature Calendar
Average daily high temperature for every day of the year. Each cell is the climatological mean for that calendar day across 55 years of NOAA data.
Best Time to Visit San Mateo, CA
Most pleasant months in San Mateo, CA: April, May, June, July, August, September, October.
What to expect on March 21st
This page shows what actually happened each year. For the odds — typical high and low, and how often it stays dry — see the climatological outlook for this date.
March 21st outlook →