Sunnyvale, CA weather in May
Sunnyvale is mild and dry in May: highs average 72°F and nights drop to about 53°F. Expect about 3 wet days. A great month for outdoor plans.
- Normal high
- 72°F
- Normal low
- 53°F
- Wet days
- 3
- 0.4 in total
- Muggy days
- 0
- dew point 65°F+
How May changes from start to finish
| May 1 | May 31 | |
|---|---|---|
| Normal high | 70°F | 74°F |
| Normal low | 51°F | 54°F |
| Chance of a wet day | 11% | 6% |
| Sunrise / sunset | 6:13 am / 7:57 pm | 5:49 am / 8:22 pm |
| Daylight | 13.7 h | 14.6 h |
Chance of a wet day: average for the first and last 7 days of the month. Times are local clock time (Pacific Time).
A typical May day
- 6 am54°Fdew point 48°F
- 9 am60°Fdew point 49°F
- Noon65°Fdew point 49°F
- 3 pm65°Fdew point 48°F
- 6 pm60°Fdew point 48°F
- 9 pm56°Fdew point 48°F
NOAA hourly normals (local standard time) from San Francisco Intl Airport (25 mi away); average wind 14 mph; clear or few clouds in 44% of daytime hours, mostly cloudy or overcast in 34%.
What kind of days to expect
- Comfortable dayshigh 65-80°F and dew point under 60°F24 of 31
- Hot dayshigh 90°F or more1 of 31
- Muggy daysdaily mean dew point 65°F or more0 of 31
- Wet daysat least 0.01 in of rain or melted snow3 of 31
- Notable rainat least 0.10 in1 of 31
- Freezing nightslow 32°F or below0 of 31
Average days per May, counted from daily records for each year 1991-2020.
Rain in May
Normal precipitation is 0.4 in; a dry May brings about 0.02 in and a wet one about 0.6 in (25th and 75th percentiles). Days with half an inch or more are rare.
How May varies from year to year
- Warmest May, 1991-20202001: average high 78°F
- Coolest May2015: average high 67°F
- Wettest May1994: 1.7 in
- Driest May2001: no measurable precipitation
- Highest reading99°F (May 15, 2008)
- Lowest reading43°F (May 10, 2003)
From the station's daily records with NOAA quality flags removed; most recent date shown when a reading repeats.
May compared with April and June
| April | May | June | |
|---|---|---|---|
| Normal high | 68°F | 72°F | 76°F |
| Normal low | 49°F | 53°F | 56°F |
| Wet days | 6 | 3 | 1 |
| Comfortable days | 18 | 24 | 23 |
| Daylight | 13.2 h | 14.2 h | 14.7 h |
Highs change by +4°F from April and +4°F into June.
Nearby alternatives in May
- Warmer: Concord, CA42 mi · high 78°F · 3 wet days
- Cooler: San Francisco, CA35 mi · high 64°F · 4 wet days
How Sunnyvale ranks in May
- Normal high237th warmest of 378 cities; 44th of 60 in California
- Wet days41st driest of 378
- Comfortable days12th most of 339
Heating and cooling
May has 116 heating degree days and 26 cooling degree days (base 65°F), 5% of the year's total heating and cooling demand.
Questions
How hot is Sunnyvale in May?
The normal high is 72°F and the normal low is 53°F. From 1991 to 2020 the hottest May reading was 99°F (most recently on May 15, 2008).
Does it rain a lot in Sunnyvale in May?
About 3 days in May have at least 0.01 in of precipitation, and the normal total is 0.4 in. The wettest May in 1991-2020 was in 1994 (1.7 in); the driest was in 2001, with no measurable precipitation.
Is May a good time to visit Sunnyvale?
May ranks 3rd of 12 months on our comfort score for Sunnyvale (88 out of 100). It has about 24 comfortable days and about 1 day at 90°F or hotter. The best months are May, June and July.
Where the numbers come from
- Temperature, rain and frost dates: Moffett Federal Airfield (USW00023244), 2.6 mi NNW of the city center, 39 ft (85 ft lower than the city). NOAA normals and daily records, 1991-2020.
- Snowfall: Palo Alto (USC00046646), 7.7 mi NW of the city center, 25 ft (99 ft lower than the city). NOAA normals and daily records, 1991-2020.
- Snow depth: Newark (USC00046144), 10 mi N of the city center, 10 ft (114 ft lower than the city). NOAA normals and daily records, 1991-2020.
- Humidity and wind by hour and cloud cover: San Francisco Intl Airport (USW00023234), 25 mi NW of the city center, 8 ft (116 ft lower than the city). NOAA normals and daily records, 1991-2020.
- Daily humidity and wind: N Y. Mineta Sn Jo Intl Apt (724945-23293), 6.2 mi E of the city center, 49 ft (75 ft lower than the city). Hourly observations, 1991-2020.