July is one of the warmer months of the year in Sunnyvale, with average highs near 30.1°C and lows around 11.8°C (mean 21°C). It is one of the drier months, averaging 1 mm of rainfall and 60% relative humidity across the period.
July is one of the warmer months of the year in Sunnyvale. Across 45 years of records, the warmest July in Sunnyvale was 1984 — when the month averaged 23.6°C — while the coldest was 2011 at 18.9°C. Typical July days reach 30.1°C with nights near 11.8°C. The long-term July temperature trend is broadly flat.
July is one of the drier months in Sunnyvale, averaging 1 mm of rainfall. The wettest Julys on record were 1997, 1999 and 2005 with 2 mm, while the driest were 2017, 2019 and 2023, among others at 0 mm.
Relative humidity in Sunnyvale during July averages 60%. The most humid July was 2011 at 68%, and the least humid was 1984 at 47%.
July receives about 6.5 kWh/m²/day of solar energy in Sunnyvale. The sunniest July was 1989 at 7.3 kWh/m²/day, and the cloudiest was 1994 at 5.6.
Average wind speed in Sunnyvale during July is 2.8 m/s. The windiest Julys were 2021 and 2022 at 3.1 m/s, while the calmest were 1995 and 1996 at 2.4 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 21.2°C | 21.1°C | 21.0°C | 20.6°C | 20.8°C | -0.4°C |
| Avg High | 31.0°C | 30.4°C | 30.1°C | 29.4°C | 29.7°C | -1.3°C |
| Avg Low | 11.5°C | 11.9°C | 12.0°C | 11.9°C | 11.9°C | +0.4°C |
| Avg Rain | 0 mm | 1 mm | 1 mm | 0 mm | 1 mm | +0 mm |
July temperatures in Sunnyvale have fallen by about 0.6°C between 1981–1985 and 2021–2025.
July has ranged from a record low of 7.8°C (2006) to a record high of 45.3°C (2006).
Rainfall in July is one of the drier months, averaging 1 mm, with a wettest year of 2 mm.
Daytime highs and overnight lows have shifted differently — highs fell about 0.4°C per decade while lows rose 0.1°C per decade, narrowing the gap between day and night.
One of the best times to visit Sunnyvale
July is one of the best times to visit Sunnyvale. Expect days averaging 30.1°C and nights around 11.8°C (mean 21°C) — warmer than Sunnyvale's yearly average — with low rainfall (1 mm), so conditions are generally comfortable for sightseeing and outdoor plans.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 27.9°C | 19.4°C | 11.0°C | 37.1°C | 9.6°C | 0 mm | 65% | 3 m/s | 6.6 |
| 2024 | 33.0°C | 23.3°C | 13.6°C | 43.2°C | 10.8°C | 0 mm | 55% | 2.8 m/s | 6.9 |
| 2023 | 29.2°C | 20.5°C | 11.9°C | 39.3°C | 9.5°C | 0 mm | 63% | 2.9 m/s | 6.9 |
| 2022 | 27.9°C | 19.8°C | 11.7°C | 35.7°C | 9.5°C | 2 mm | 65% | 3.1 m/s | 6.6 |
| 2021 | 30.1°C | 21.0°C | 12.0°C | 39.5°C | 10.0°C | 0 mm | 58% | 3.1 m/s | 6.3 |
| 2020 | 29.9°C | 20.6°C | 11.3°C | 35.3°C | 9.2°C | 0 mm | 61% | 2.9 m/s | 6.8 |
| 2019 | 28.0°C | 19.9°C | 11.9°C | 39.2°C | 9.9°C | 0 mm | 67% | 3 m/s | 6.9 |
| 2018 | 31.1°C | 21.9°C | 12.8°C | 34.9°C | 9.3°C | 0 mm | 58% | 2.9 m/s | 6.5 |
| 2017 | 30.8°C | 21.2°C | 11.6°C | 38.5°C | 9.8°C | 0 mm | 59% | 2.9 m/s | 7 |
| 2016 | 29.6°C | 20.5°C | 11.4°C | 40.3°C | 9.7°C | 0 mm | 60% | 3 m/s | 6.9 |
| 2015 | 29.8°C | 21.8°C | 13.8°C | 40.2°C | 10.0°C | 1 mm | 62% | 2.8 m/s | 6.3 |
| 2014 | 31.6°C | 22.5°C | 13.4°C | 38.3°C | 9.2°C | 0 mm | 58% | 2.8 m/s | 6.2 |
| 2013 | 29.9°C | 20.9°C | 11.9°C | 38.2°C | 9.2°C | 0 mm | 60% | 3 m/s | 6 |
| 2012 | 28.5°C | 19.7°C | 10.9°C | 39.1°C | 9.2°C | 0 mm | 63% | 2.8 m/s | 6.5 |
| 2011 ❄️ | 26.9°C | 18.9°C | 10.8°C | 35.5°C | 9.2°C | 0 mm | 68% | 2.7 m/s | 6.4 |
| 2010 | 27.5°C | 19.1°C | 10.8°C | 34.6°C | 8.7°C | 0 mm | 67% | 2.8 m/s | 6.3 |
| 2009 | 29.7°C | 20.6°C | 11.5°C | 39.9°C | 8.8°C | 0 mm | 61% | 2.8 m/s | 6.5 |
| 2008 | 30.2°C | 21.1°C | 12.0°C | 43.3°C | 9.5°C | 0 mm | 63% | 2.8 m/s | 6.5 |
| 2007 | 29.6°C | 20.8°C | 12.0°C | 41.4°C | 9.7°C | 0 mm | 66% | 2.8 m/s | 6.7 |
| 2006 | 32.3°C | 22.9°C | 13.6°C | 45.3°C | 7.8°C | 0 mm | 59% | 2.5 m/s | 7.1 |
| 2005 | 31.8°C | 22.2°C | 12.6°C | 40.4°C | 10.0°C | 2 mm | 60% | 2.7 m/s | 6.7 |
| 2004 | 29.3°C | 20.6°C | 11.9°C | 36.7°C | 9.9°C | 0 mm | 64% | 2.9 m/s | 6.1 |
| 2003 | 31.3°C | 21.8°C | 12.3°C | 40.3°C | 9.0°C | 2 mm | 60% | 2.9 m/s | 6.7 |
| 2002 | 29.7°C | 20.6°C | 11.5°C | 41.2°C | 9.4°C | 0 mm | 63% | 2.9 m/s | 6.6 |
| 2001 | 29.0°C | 20.4°C | 11.8°C | 42.7°C | 9.4°C | 1 mm | 61% | 2.9 m/s | 6.2 |
| 2000 | 27.6°C | 19.2°C | 10.8°C | 39.9°C | 9.2°C | 1 mm | 65% | 2.9 m/s | 6.4 |
| 1999 | 27.8°C | 19.3°C | 10.8°C | 42.5°C | 7.9°C | 2 mm | 61% | 2.8 m/s | 6.6 |
| 1998 | 28.4°C | 20.0°C | 11.6°C | 38.7°C | 9.4°C | 0 mm | 68% | 2.5 m/s | 6.4 |
| 1997 🌧️ | 30.5°C | 21.2°C | 11.9°C | 37.2°C | 9.1°C | 2 mm | 62% | 2.8 m/s | 6.5 |
| 1996 | 32.9°C | 22.9°C | 12.8°C | 39.1°C | 8.9°C | 1 mm | 52% | 2.4 m/s | 6.4 |
| 1995 | 29.0°C | 20.6°C | 12.3°C | 38.8°C | 9.5°C | 0 mm | 65% | 2.4 m/s | 7 |
| 1994 | 30.4°C | 20.7°C | 11.0°C | 36.2°C | 9.1°C | 1 mm | 58% | 2.6 m/s | 5.6 |
| 1993 | 30.6°C | 20.9°C | 11.1°C | 40.2°C | 8.8°C | 1 mm | 59% | 2.5 m/s | 6.7 |
| 1992 | 30.5°C | 21.6°C | 12.7°C | 35.6°C | 8.5°C | 0 mm | 60% | 2.5 m/s | 6.3 |
| 1991 | 31.8°C | 21.8°C | 11.9°C | 39.2°C | 9.6°C | 0 mm | 58% | 2.5 m/s | 6.2 |
| 1990 | 32.0°C | 22.2°C | 12.5°C | 40.0°C | 9.5°C | 0 mm | 57% | 2.5 m/s | 6.3 |
| 1989 | 30.1°C | 20.3°C | 10.5°C | 38.8°C | 8.7°C | 0 mm | 60% | 3 m/s | 7.3 |
| 1988 | 33.8°C | 23.3°C | 12.8°C | 42.4°C | 9.0°C | 0 mm | 53% | 2.7 m/s | 6.5 |
| 1987 | 27.9°C | 19.2°C | 10.4°C | 36.2°C | 8.0°C | 0 mm | 63% | 2.9 m/s | 7.1 |
| 1986 | 31.3°C | 21.3°C | 11.4°C | 37.0°C | 8.7°C | 1 mm | 56% | 2.5 m/s | 6.4 |
| 1985 | 33.3°C | 23.0°C | 12.8°C | 38.6°C | 10.5°C | 2 mm | 50% | 2.6 m/s | 6.2 |
| 1984 🔥 | 33.9°C | 23.6°C | 13.3°C | 41.4°C | 8.9°C | 0 mm | 47% | 2.5 m/s | 6.4 |
| 1983 | 27.7°C | 19.3°C | 11.0°C | 36.2°C | 8.3°C | 1 mm | 66% | 2.7 m/s | — |
| 1982 | 29.1°C | 19.8°C | 10.5°C | 35.2°C | 8.8°C | 0 mm | 63% | 2.6 m/s | — |
| 1981 | 31.6°C | 21.3°C | 11.0°C | 38.3°C | 8.6°C | 0 mm | 53% | 2.6 m/s | — |
Actual recorded July data for each year, 1981–2025 — sourced from NASA POWER.
The average high in July is around 30.1°C with lows near 11.8°C (mean 21°C), based on 45 years of NASA POWER data.
July averages 1 mm of rainfall in Sunnyvale, one of the drier months. The wettest on record was 2 mm in 1997.
The hottest July reached 45.3°C in 2006. The coldest dipped to 7.8°C in 2006.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average July temperatures have fallen by about 0.6°C — but days and nights have moved in opposite directions. Overnight lows rose from 11.7°C to 12°C while daytime highs eased from 31.1°C to 29.6°C, narrowing the gap between day and night.
July is one of the warmer months of the year in Sunnyvale and one of the drier months, so plan for around 30.1°C daytime highs and 11.8°C at night.
Not quite — July is the 11th coolest month in Sunnyvale, averaging 21°C.
For July in Sunnyvale, pack light, breathable clothing and sun protection, with typical highs of 30.1°C and lows of 11.8°C.
Relative humidity in July averages 60% — moderately humid.
Average wind speed in July is 2.8 m/s. The windiest July on record averaged 3.1 m/s (2021).
The wettest July on record was 1997 with 2 mm. On average, July sees 1 mm.
All figures are derived from NASA POWER (Prediction Of Worldwide Energy Resources), based on MERRA-2 satellite reanalysis, covering 1981–2025.
Explore how the weather in Sunnyvale behaves each July, based on 45 years of NASA POWER climate data from 1981 to 2025. This page breaks down average temperatures, rainfall, humidity, wind and solar radiation for July specifically, along with year-by-year records and how the month has changed over the decades.
