Diablo Grande Weather in May
Average highs run from 84°F on May 1 to 92°F on May 31, and lows from 49°F to 55°F. Normal precipitation for the month is 0.45 in over about 2 wet days.
May day by day
The normal high and low for each date, and the record, in °F.
- Normal low
- Normal high
- Record high
- Record low
May at a glance
- Average high
- 88°F
- Average low
- 52°F
- Precipitation
- 0.45 in
- Record high
- 105°FMay 29, 1984
- Record low
- 34°FMay 4, 1952
- Chance of a freeze
- 4%
- Days of 90°F or more
- 11.4
- Daylight
- 13 h 45 min to 14 h 34 min
- Cloud cover
- 33%
- Humidity
- 61%
- Dew point
- 46°F
- Wind
- 9.2 mph
Every day of the month
A wet day has at least 0.01 inch of precipitation.
| Date | Normal high | Normal low | Record high | Record low | Chance wet |
|---|---|---|---|---|---|
| May 1 | 84°F | 49°F | 97°F 1981 | 38°F 1983 | 11% |
| May 2 | 85°F | 49°F | 95°F 1996 | 35°F 1983 | 11% |
| May 3 | 85°F | 50°F | 93°F 1966 | 38°F 1983 | 11% |
| May 4 | 85°F | 50°F | 97°F 1990 | 34°F 1952 | 10% |
| May 5 | 85°F | 50°F | 97°F 1987 | 37°F 1952 | 10% |
| May 6 | 86°F | 50°F | 100°F 1987 | 40°F 1975 | 10% |
| May 7 | 86°F | 50°F | 99°F 1987 | 36°F 2021 | 10% |
| May 8 | 86°F | 51°F | 95°F 1984 | 36°F 1971 | 10% |
| May 9 | 86°F | 51°F | 97°F 2001 | 41°F 1963 | 9% |
| May 10 | 87°F | 51°F | 97°F 1993 | 39°F 1982 | 9% |
| May 11 | 87°F | 51°F | 97°F 1987 | 38°F 1982 | 9% |
| May 12 | 87°F | 51°F | 96°F 1987 | 39°F 1993 | 9% |
| May 13 | 87°F | 52°F | 98°F 1976 | 42°F 1982 | 9% |
| May 14 | 88°F | 52°F | 101°F 1976 | 38°F 1982 | 8% |
| May 15 | 88°F | 52°F | 102°F 1972 | 41°F 1998 | 8% |
| May 16 | 88°F | 52°F | 98°F 2008 | 41°F 2026 | 8% |
| May 17 | 88°F | 52°F | 103°F 2008 | 36°F 2002 | 8% |
| May 18 | 89°F | 53°F | 104°F 2009 | 38°F 1998 | 8% |
| May 19 | 89°F | 53°F | 102°F 2008 | 38°F 2002 | 8% |
| May 20 | 89°F | 53°F | 98°F 1966 | 38°F 2021 | 7% |
| May 21 | 89°F | 53°F | 99°F 1988 | 37°F 1971 | 7% |
| May 22 | 89°F | 53°F | 98°F 1967 | 38°F 1960 | 7% |
| May 23 | 90°F | 54°F | 99°F 2000 | 41°F 2021 | 7% |
| May 24 | 90°F | 54°F | 98°F 2001 | 36°F 2021 | 6% |
| May 25 | 90°F | 54°F | 98°F 1982 | 37°F 1990 | 6% |
| May 26 | 90°F | 54°F | 101°F 1951 | 34°F 2021 | 6% |
| May 27 | 91°F | 54°F | 100°F 1951 | 41°F 2026 | 6% |
| May 28 | 91°F | 54°F | 101°F 2020 | 42°F 1959 | 6% |
| May 29 | 91°F | 54°F | 105°F 1984 | 43°F 1977 | 5% |
| May 30 | 91°F | 55°F | 104°F 1950 | 41°F 1982 | 5% |
| May 31 | 92°F | 55°F | 102°F 2025 | 41°F 1988 | 5% |
Chance of rain
- Chance of a wet day
Sunrise and sunset
Times for 2026, local time (PDT).
- May 1
- sunrise 6:10 AM, sunset 7:55 PM
- May 31
- sunrise 5:46 AM, sunset 8:20 PM
Other months
Sources
Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00046168 (Newman), public domain. Records: NOAA GHCN-Daily, station USC00048999, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.