Historical weather data, all-time temperature records, and monthly climate averages for San Luis Obispo, CA. Explore typical weather conditions by week for trip planning, and see how today compares to the historical record.
April 5th in San Luis Obispo is a mild, mostly dry affair — historically speaking, expect a high near 68° and a low around 45°. There's a 22% chance of rain, so a light jacket isn't a bad call. The date has seen some wild swings though: a scorching 90° back in 1961 and a sharp 34° low in 1999.
San Luis Obispo's weather has some teeth when it wants to. The all-time high hit a brutal 113° on September 6, 2020, while the coldest day on record plunged to 17° on December 23, 1990. A single January storm in 2023 dumped 6.05 inches of rain — the most ever recorded in one day.
San Luis Obispo is famously temperate year-round, with average highs ranging from just 63° in early January to 80° in late August — hardly a dramatic swing. If you're chasing warmth, late summer through early fall is your window; if you want to avoid rain, skip the last week of December, the wettest stretch of the year at 1.54 inches on average.