Modesto climate
Modesto (California, United States) has a hot-summer Mediterranean climate (Köppen Csa). The average temperature over the year is 17 °C63 °F, and about 421 mm17 in of precipitation falls in an average year.
Temperature by month
Precipitation by month
Modesto climate table
| Month | High °C°F | Low °C°F | Mean °C°F | Precip. mmin |
|---|---|---|---|---|
| Jan | 1558 | 541 | 1049 | 742.9 |
| Feb | 1661 | 542 | 1151 | 732.9 |
| Mar | 1966 | 744 | 1355 | 622.5 |
| Apr | 2271 | 846 | 1559 | 341.3 |
| May | 2781 | 1051 | 1966 | 130.5 |
| Jun | 3392 | 1356 | 2374 | 30.1 |
| Jul | 38100 | 1660 | 2780 | 00.0 |
| Aug | 3698 | 1559 | 2678 | 10.0 |
| Sep | 3392 | 1458 | 2475 | 30.1 |
| Oct | 2780 | 1152 | 1966 | 210.8 |
| Nov | 2067 | 745 | 1356 | 431.7 |
| Dec | 1458 | 541 | 1049 | 943.7 |
| Year | 38100 | 541 | 1763 | 42117 |
“Year” row: highest monthly high, lowest monthly low, annual mean and annual total.
| Month | Humid. | Cloud | Solar | Daylight |
|---|---|---|---|---|
| Jan | 80% | 59% | 2.3 | 9:50 |
| Feb | 79% | 51% | 3.5 | 10:45 |
| Mar | 77% | 48% | 4.9 | 11:51 |
| Apr | 70% | 40% | 6.3 | 13:07 |
| May | 59% | 28% | 7.6 | 14:11 |
| Jun | 48% | 14% | 8.4 | 14:45 |
| Jul | 41% | 11% | 8.2 | 14:31 |
| Aug | 44% | 11% | 7.4 | 13:36 |
| Sep | 46% | 15% | 6.0 | 12:22 |
| Oct | 53% | 27% | 4.4 | 11:09 |
| Nov | 67% | 44% | 2.9 | 10:05 |
| Dec | 77% | 58% | 2.1 | 9:34 |
Humid. = average relative humidity at 2 m; cloud = average cloud amount; solar = average daily solar energy reaching the ground in kWh/m² (all-sky); daylight in hours:minutes, calculated for the 15th of each month.
What the climate of Modesto is like
The warmest month is July, with an average high of 38 °C100 °F and a low of 16 °C60 °F. The coldest is December, when highs average 14 °C58 °F and lows 5 °C41 °F. There is a clear seasonal cycle, with 17 °C30.6 °F between the average temperature of the warmest and the coolest month.
Annual precipitation is moderate at about 421 mm17 in. The wettest three-month stretch is December–February, which brings 57% of the annual total. Months with less than 20 mm0.8 in on average: May–September. The wettest month is December (94 mm3.7 in), the driest is July (0 mm0.0 in).
Relative humidity ranges from 41% in July to 80% in January. The clearest skies (lowest average cloud amount, 11%) are typical of August. Average wind speed near the ground ranges from 6 km/h (4 mph) in January to 12 km/h (7 mph) in June. Daylight lasts from about 9.6 hours in December to 14.7 hours in June.
Best time to visit Modesto
Based on these averages, the most comfortable months for sightseeing and outdoor activities are March–May and October and November: average highs of 19 °C66 °F to 27 °C81 °F with 13 mm0.5 in to 62 mm2.5 in of precipitation per month.
The most challenging month is July, which is hot, with average highs of 38 °C100 °F.
Comfort score: months are ranked by how close they come to an average high of 21–28 °C (70–82 °F), lows above 5 °C (41 °F), little precipitation and moderate humidity. The best-ranked months of each place are recommended, even where none meets all of these. These are general rules of thumb applied to long-term averages.
What to pack for Modesto
- Winter (December–February) — highs 1458 to 16 °C61 °F, lows around 5 °C41 °F, about 80 mm3.1 in of precipitation a month. Pack long sleeves, a sweater and a medium jacket and an extra layer for the cooler mornings and evenings.
- Spring (March–May) — highs 1966 to 27 °C81 °F, lows 744 to 10 °C51 °F, about 36 mm1.4 in of precipitation a month. Pack light layers — T-shirts plus a light sweater or jacket and an extra layer for the cooler mornings and evenings.
- Summer (June–August) — highs 3392 to 38 °C100 °F, lows 1356 to 16 °C60 °F, about 1 mm0.1 in of precipitation a month. Pack very light, breathable clothing, a sun hat and plenty of water and an extra layer for the cooler mornings and evenings.
- Autumn (September–November) — highs 2067 to 33 °C92 °F, lows 745 to 14 °C58 °F, about 22 mm0.9 in of precipitation a month. Pack light summer clothes such as T-shirts, shorts or light dresses and an extra layer for the cooler mornings and evenings.
How Modesto compares
Compared with Stockton, about 44 km to the northwest, Modesto is on average 0.4 °C0.8 °F warmer and receives 6% less precipitation (421 mm17 in vs 449 mm18 in). The difference is largest in July (1.1 °C2.1 °F warmer).
Of the 222 places in the United States covered by World Climates, Modesto is the 76th warmest by annual mean temperature and the 185th wettest by annual precipitation. See all of them on the United States climate page.
Places in other countries with the most similar temperature and rainfall pattern: Irbid (Jordan, Csa), Nablus (Palestine, Csa) and Jerusalem (Israel, Csa).
Nearby places
- Stockton 44 km · 17 °C63 °F · 449 mm18 in
- Antioch 82 km · 15 °C60 °F · 467 mm18 in
- San Jose 86 km · 15 °C60 °F · 511 mm20 in
- Hayward 95 km · 15 °C59 °F · 511 mm20 in
- Concord 98 km · 15 °C59 °F · 467 mm18 in
- Sacramento 113 km · 17 °C63 °F · 567 mm22 in
- Fairfield 114 km · 15 °C60 °F · 467 mm18 in
- Salinas 122 km · 14 °C58 °F · 479 mm19 in
Frequently asked questions
What is the warmest month in Modesto?
July is the warmest month in Modesto, with an average high of 38 °C (100 °F) and an average low of 16 °C (60 °F).
What is the coldest month in Modesto?
December is the coldest month, with an average high of 14 °C (58 °F) and an average low of 5 °C (41 °F).
When does it rain the most in Modesto?
December is the wettest month with about 94 mm (3.7 in) of precipitation; July is the driest with about 0 mm (0.0 in).
What is the best time to visit Modesto?
Judging by long-term averages, the most comfortable months are March–May and October and November.
About this data
All figures are 25-year averages (January 2001 – December 2025) from the NASA POWER project. Temperature, humidity, wind and precipitation come from the MERRA-2 reanalysis (precipitation is the bias-corrected MERRA-2 product), cloud and solar values from CERES satellite data. They describe a grid cell of roughly 50–70 km, not a single weather station, so they can differ from airport records — most of all on coasts, in mountains and for rainfall. Average highs and lows are the monthly mean temperature plus/minus half of the average daily temperature range. Counts of rainy days are not part of this dataset.
The grid cell’s average elevation is 254 m, while Modesto lies at about 28 m. Temperatures on this page were therefore adjusted by +1.5 °C2.6 °F using the standard lapse rate of 6.5 °C per 1,000 m.