Gilroy, United States experiences average highs of 21°C (70°F) and lows of 11°C (52°F) throughout the year. The climate is relatively dry, with only 4 rainy days per month on average. Sunshine is abundant, averaging about 10 hours per day. Average highs have stayed broadly stable across the available records.
Gilroy, United States Weather & Climate 2026
Monthly climate averages for Gilroy, United States. Based on 10-year ERA5 reanalysis data.
Climate Overview
Drier season: May–Oct 
Wetter season: Jan–Dec At-a-Glance Climate Summary
Live Weather & Air Quality
Key figures
Climate Score
8.3/10
Best: June, July, August, September, October
UV Index
6
High
Temperature 21°C / 11°C
Feels Like 21°C / 10°C
Rainy Days 4
Rainfall 36 mm
Sunshine 10 h
Humidity 72%
Wind Speed 12 km/h
Dew Point 11°C
Hottest Month
27°C
August
Avg Low16°C
Rain0days
Coldest Month
7°C
January
Avg High16°C
Rain9days
Driest Month
0days
June
Avg High25°C
Avg Low13°C
Windiest Month
14 km/h
May (Gusts 39)
Sea Temperature
13°C – 17°C
Warmest water: September (
17.3°C
)
Worst Time to Visit
Consider avoiding January, February, December due to less favorable weather conditions.
Sun Position
Sunrise 05:47
Daylight 14.7h
Sunset 20:29
Live conditions—
Gilroy on the map · live conditions
Gilroy, United States
- Continent
- Americas
- Country
- United States
- City
- Gilroy
- Population
- 53.2K
- Elevation
- 61 m
- Coordinates
- 37.01°, -121.57°
Seasonal Breakdown
Spring
Mar–May
Avg High 20°C
Avg Low 10°C
Rain 5 days/mo
Summer
Jun–Aug
Avg High 26°C
Avg Low 14°C
Rain 0 days/mo
3/3 best months
Autumn
Sep–Nov
Avg High 23°C
Avg Low 12°C
Rain 3 days/mo
2/3 best months
Winter
Dec–Feb
Avg High 16°C
Avg Low 7°C
Rain 8 days/mo
Climate Charts
Based on historical averages (2016–2025)
Monthly Temperatures
HighLowShaded bands show the typical range across the available yearly records.
Line chart showing monthly temperatures. Jan: 16°C / 7°C . Feb: 17°C / 7°C . Mar: 17°C / 8°C . Apr: 20°C / 10°C . May: 22°C / 11°C . Jun: 25°C / 13°C . Jul: 27°C / 15°C . Aug: 27°C / 16°C . Sep: 27°C / 16°C . Oct: 24°C / 13°C . Nov: 19°C / 9°C . Dec: 16°C / 7°C .
Monthly Rainfall
Rainfall
Bar chart showing monthly rainfall. Jan: 106 mm. Feb: 72 mm. Mar: 83 mm. Apr: 23 mm. May: 12 mm. Jun: 0 mm. Jul: 0 mm. Aug: 0 mm. Sep: 2 mm. Oct: 19 mm. Nov: 40 mm. Dec: 78 mm.
Monthly Humidity
Humidity
Line chart showing monthly humidity. Jan: 79%. Feb: 73%. Mar: 76%. Apr: 74%. May: 71%. Jun: 66%. Jul: 67%. Aug: 69%. Sep: 69%. Oct: 66%. Nov: 72%. Dec: 77%.
Monthly Wind Speed
Wind SpeedGusts
Bar chart showing monthly wind speed. Jan: 11 km/h . Feb: 12 km/h . Mar: 13 km/h . Apr: 13 km/h . May: 14 km/h . Jun: 13 km/h . Jul: 12 km/h . Aug: 11 km/h . Sep: 11 km/h . Oct: 9 km/h . Nov: 9 km/h . Dec: 9 km/h .
Sunshine
Sunshine
Sunshine: Jan: 7h. Feb: 9h. Mar: 10h. Apr: 11h. May: 13h. Jun: 14h. Jul: 13h. Aug: 12h. Sep: 11h. Oct: 10h. Nov: 8h. Dec: 7h.
Sea Temperature
Sea Temperatureswim
Line chart showing monthly sea temperature. Jan: 13°C . Feb: 13°C . Mar: 13°C . Apr: 13°C . May: 14°C . Jun: 15°C . Jul: 16°C . Aug: 17°C . Sep: 17°C . Oct: 17°C . Nov: 14°C . Dec: 13°C .
UV Index
UV Index
Bar chart showing monthly UV index. Jan: UV 3. Feb: UV 4. Mar: UV 6. Apr: UV 7. May: UV 8. Jun: UV 8. Jul: UV 8. Aug: UV 8. Sep: UV 7. Oct: UV 5. Nov: UV 4. Dec: UV 3.
Monthly Daylight Hours
Daylight12h reference
Monthly Dew Point & Comfort
Dew Point Dry Comfortable Humid Muggy Oppressive
Climate Trends
Average highs have stayed broadly stable across the available records. Average rainfall is trending drier by about 11 mm.
2016 to 2025
Avg high Avg rainfall
Climate summary
| Last 12 months | All years | |
|---|---|---|
| Hottest month | Aug 2025 · 27°C | Aug · 27°C |
| Coldest month | Jan 2025 · 5°C | Jan · 7°C |
| Wettest month | Feb 2025 · 96 mm | Jan · 106 mm |
| Windiest month | Mar 2025 · 16 km/h | May · 14 km/h |
Month-by-Month Weather Table
January
Fair 
February
Fair March
Good April
Good May
Excellent June best
Excellent July best
Excellent August best
Excellent September best
Excellent October best
Excellent November
Good December
Fair | Month | Temp | Feels Like | Rain | Sun | Humidity | UV | Status | Details |
|---|---|---|---|---|---|---|---|---|
| January | 16°C / 7°C | 14°C / 5°C | 9days (106 mm) Wet | 7.1h Good | 79% Humid | 3.1 Moderate | Fair | View Details |
| February | 17°C / 7°C | 15°C / 5°C | 7days (72 mm) Good | 8.7h Good | 73% Muggy | 4 Moderate | Fair | View Details |
| March | 17°C / 8°C | 16°C / 6°C | 10days (83 mm) Wet | 9.6h Good | 76% Humid | 5.5 High | Good | View Details |
| April | 20°C / 10°C | 20°C / 9°C | 3days (23 mm) Excellent | 11h Excellent | 74% Muggy | 6.7 High | Good | View Details |
| May | 22°C / 11°C | 22°C / 10°C | 2days (12 mm) Excellent | 12.6h Excellent | 71% Muggy | 7.9 Very High | Excellent | View Details |
| June best | 25°C / 13°C | 26°C / 13°C | 0days (0 mm) Excellent | 13.5h Excellent | 66% Muggy | 8.2 Very High | Excellent | View Details |
| July best | 27°C / 15°C | 28°C / 15°C | 0days (0 mm) Excellent | 13.3h Excellent | 67% Muggy | 8.3 Very High | Excellent | View Details |
| August best | 27°C / 16°C | 29°C / 16°C | 0days (0 mm) Excellent | 12.4h Excellent | 69% Muggy | 7.8 Very High | Excellent | View Details |
| September best | 27°C / 16°C | 28°C / 16°C | 1days (2 mm) Excellent | 11.4h Excellent | 69% Muggy | 6.6 High | Excellent | View Details |
| October best | 24°C / 13°C | 24°C / 13°C | 2days (19 mm) Excellent | 9.8h Good | 66% Muggy | 5.2 High | Excellent | View Details |
| November | 19°C / 9°C | 18°C / 7°C | 5days (40 mm) Good | 8.4h Good | 72% Muggy | 3.6 Moderate | Good | View Details |
| December | 16°C / 7°C | 15°C / 5°C | 8days (78 mm) Wet | 7h Good | 77% Humid | 2.9 Moderate | Fair | View Details |
Compare Nearby City Climates
Frequently Asked Questions
The best months to visit Gilroy are June, July, August, September, October, when temperatures are comfortable and rainfall is at its lowest. This is based on 10-year climate averages for Gilroy, scoring temperature, rainfall, humidity, and sunshine hours.
The hottest month in Gilroy is August, with average daytime highs of 27°C (81°F). Plan outdoor activities for early morning or late afternoon if visiting during this period.
The coldest month in Gilroy is January, with average overnight lows of 7°C (44°F). Pack warm layers and expect shorter daylight hours during this period.
The wettest month in Gilroy is January, averaging 106mm of precipitation across 9 rainy days. An umbrella or waterproof jacket is essential.
Gilroy receives approximately 125 sunshine hours per year. The sunniest month is June with around 14 hours. Based on climate data for Gilroy.
The least favorable months to visit Gilroy are January, February, December, primarily due to less favorable weather conditions. For the best conditions, consider June, July, August, September, October instead.
The annual average UV index in Gilroy is 6, classified as high. Standard sun protection (sunscreen, hat) is recommended during prolonged outdoor exposure.
Average humidity in Gilroy is 72%, classified as moderate. Humidity levels are generally comfortable and should not affect outdoor activities for most people.
Sea temperatures in Summer average 15°C (59°F), which most swimmers will find too cold without a wetsuit.
Average wind speeds in Gilroy are 12 km/h (7 mph). The windiest month is May with peak winds reaching 14 km/h (9 mph) (gusts up to 39 km/h / 24 mph).
Gilroy averages 10 clear-sky days per month with overall cloud cover around 40%. The clearest skies occur in August.
The annual average dew point in Gilroy is 11°C (52°F), which feels pleasant with low humidity. Outdoor activities are comfortable year-round from a humidity standpoint.
Gilroy has a Warm-Summer Mediterranean climate, classified as Csb under the Köppen system. Temperate climates have mild winters and warm summers, with rainfall spread across the year and four distinct seasons.
The 'feels like' temperature in Gilroy ranges from 10°C (50°F) to 21°C (70°F) on average. The 'feels like' temperature closely matches the actual temperature throughout most of the year.
Yes, June is a great time to visit Gilroy. It earns a climate score of 9.5/10 with Excellent.
For June in Gilroy, pack Breathable clothing, Sunscreen (SPF 30+), Sun hat, Sunglasses, Comfortable walking shoes. With average highs of 25°C (77°F) and 0 rainy days, these essentials will keep you comfortable.
Data Source
Climate data derived from ERA5 reanalysis (ECMWF), averaged over 2016–2025. Sea surface temperature from marine reanalysis data. Climate scores and seasonal estimates are computed by WorldStats.
Last updated: