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Costa Mesa, CA Weather on April 20
April 20th in Costa Mesa, CA typically brings pleasant spring weather, with average highs around 73°F and lows near 54°F. Over 55 years of records, the warmest April 20th was in 2009 (79°F average), while the coldest was 1995 (55°F) — a 24°F range across recorded history. Rain or other precipitation has occurred on about 11% of April 20th dates historically, with the wettest April 20th recording 2.29" of rain. The last decade has been 2.5°F warmer on this date compared to 20-30 years ago.
What to Expect on April 20
Planning for April 20th in Costa Mesa, CA? Great weather for outdoor activities.
April 20 Weather Records for Costa Mesa
- •The all-time record high for April 20th in Costa Mesa, CA is 98°F, set in 2009.
- •The coldest April 20th on record dropped to 43°F in 1972.
- •Temperatures have reached 90°F or higher on April 20th in 3 of the last 55 years.
- •Last year (1971), April 20th was 9°F cooler than the long-term average.
Frequently Asked Questions
What was the warmest April 20 ever in Costa Mesa?
The warmest April 20 in Costa Mesa, CA reached 98°F in 2009. That is 25°F above the long-term average high of 73°F.
What was the coldest April 20 ever in Costa Mesa?
The coldest April 20 in Costa Mesa, CA dropped to 43°F in 1972. That is 11°F below the long-term average low of 54°F.
What is the average temperature on April 20 in Costa Mesa?
On April 20, Costa Mesa averages a high of 73°F and a low of 54°F based on 55 years of NOAA weather observations from SANTA ANA JOHN WAYNE AP.
How many years of weather data are available for April 20 in Costa Mesa?
We have 55 years of weather records for April 20 in Costa Mesa, CA, sourced from NOAA's Global Historical Climatology Network. Records include daily high and low temperatures, precipitation, and snowfall data going back to 2025.
April 20 Weather History in Costa Mesa
| Year | High | Low | Precip | Snow |
|---|---|---|---|---|
| 2025 | 70°F | 54°F | 0" | -- |
| 2024 | 75°F | 58°F | 0" | -- |
| 2023 | 77°F | 53°F | 0" | -- |
| 2022 | 69°F | 59°F | 0" | -- |
| 2021 | 68°F | 58°F | 0" | -- |
| 2020 | 71°F | 62°F | 0" | -- |
| 2019 | 66°F | 57°F | 0" | -- |
| 2018 | 73°F | 53°F | 0" | -- |
| 2017 | 74°F | 57°F | 0" | -- |
| 2016 | 85°F | 59°F | 0" | -- |
| 2015 | 68°F | 59°F | 0" | -- |
| 2014 | 74°F | 59°F | 0" | -- |
| 2013 | 77°F | 53°F | 0" | -- |
| 2012 | 74°F | 56°F | 0" | -- |
| 2011 | 69°F | 58°F | 0.13" | -- |
| 2010 | 69°F | 54°F | 0.1" | -- |
| 2009 | 98°F | 60°F | 0" | -- |
| 2008 | 66°F | 53°F | 0" | -- |
| 2007 | 58°F | 52°F | 0.58" | -- |
| 2006 | 76°F | 53°F | 0" | -- |
| 2005 | 68°F | 50°F | 0" | -- |
| 2004 | 68°F | 53°F | 0" | -- |
| 2003 | 72°F | 52°F | 0" | -- |
| 2002 | 67°F | 52°F | 0" | -- |
| 2001 | 64°F | 51°F | 0.05" | -- |
| 2000 | 73°F | 53°F | 0" | -- |
| 1999 | 70°F | 57°F | 0" | -- |
| 1998 | 84°F | 54°F | 0" | -- |
| 1997 | 78°F | 60°F | 0" | -- |
| 1996 | 71°F | 52°F | 0" | -- |
| 1995 | 63°F | 47°F | 0" | -- |
| 1994 | 73°F | 57°F | 0" | -- |
| 1993 | 85°F | 57°F | 0" | -- |
| 1992 | 84°F | 52°F | 0" | -- |
| 1991 | 67°F | 57°F | 0" | -- |
| 1990 | 71°F | 58°F | 0" | -- |
| 1989 | 76°F | 60°F | 0" | -- |
| 1988 | 65°F | 51°F | 2.29" | -- |
| 1987 | 90°F | 49°F | 0" | -- |
| 1986 | 91°F | 55°F | 0" | -- |
| 1985 | 66°F | 51°F | 0" | -- |
| 1984 | 74°F | 51°F | 0" | -- |
| 1983 | 66°F | 51°F | 1.57" | -- |
| 1982 | 89°F | 54°F | 0" | -- |
| 1981 | 69°F | 49°F | 0" | -- |
| 1980 | 77°F | 56°F | 0" | -- |
| 1979 | 76°F | 49°F | 0" | -- |
| 1978 | 72°F | 53°F | 0" | -- |
| 1977 | 79°F | 52°F | 0" | -- |
| 1976 | 83°F | 52°F | 0" | -- |
| 1975 | 72°F | 48°F | 0" | -- |
| 1974 | 69°F | 51°F | 0" | -- |
| 1973 | 72°F | 45°F | 0" | -- |
| 1972 | 71°F | 43°F | 0" | -- |
| 1971 | 64°F | 51°F | 0" | -- |
Based on 55 years of data from NOAA station: SANTA ANA JOHN WAYNE AP
Monthly Climate Averages
Historical temperature and precipitation averages for Costa Mesa, CA, based on 55+ years of weather data.
Temperatures in Fahrenheit. Precipitation and snowfall in inches.