Tracy in Winter
In winter (December, January and February), Tracy sees average daytime highs around 58°F and overnight lows near 42°F, with 9.5 in of rain over about 26 wet days across the season. It is the coldest season of the year and the wettest season of the year.
Across winter, daytime highs hold fairly steady around 58°F. The sky is clear or mostly clear about 35% of the time across winter, and the air most often feels dry.
Winter is Tracy's weakest season of the year to visit on our travel score. For the whole year in context, see Tracy's year-round climate.
- Avg daytime high
- 58°F
- coldest season of the year
- Avg overnight low
- 42°F
- Rainfall
- 9.5 in
- 26 wet days
- Avg wind
- 4 mph
- Travel score
- 4.5
- weakest season of the year
- Months
- Dec · Jan · Feb
Temperature in Tracy in Winter
Across winter, daytime highs hold fairly steady around 58°F.
A typical winter day in Tracy reaches about 58°F and drops to 42°F overnight. The warmest of the three months is February, the coolest December.
Tracy weather by month
How the three winter months (December, January and February) compare with the rest of the year — the season's months are highlighted.
| Month | High / Low (°F) | Rainfall (inches) | Wet days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|
| Jan | 57° / 41° | 3.3 | 9.1 | 9.7 | 4.2 |
| Feb | 60° / 43° | 3.2 | 8.7 | 10.5 | 5.0 |
| Mar | 65° / 46° | 2.6 | 8.9 | 11.7 | 6.2 |
| Apr | 70° / 48° | 1.3 | 5 | 12.9 | 7.5 |
| May | 77° / 53° | 0.7 | 3.1 | 14 | 8.4 |
| Jun | 84° / 57° | 0.1 | 0.8 | 14.6 | 7.5 |
| Jul | 88° / 60° | 0.0 | 0.2 | 14.3 | 6.2 |
| Aug | 87° / 60° | 0.1 | 0.2 | 13.5 | 6.5 |
| Sep | 83° / 57° | 0.1 | 0.6 | 12.3 | 7.8 |
| Oct | 75° / 52° | 0.8 | 2.7 | 11 | 8.6 |
| Nov | 64° / 46° | 1.5 | 5.5 | 10 | 6.5 |
| Dec | 57° / 41° | 3.0 | 8.3 | 9.4 | 4.2 |
Cloud cover in Winter
The sky is clear or mostly clear about 35% of the time across winter.
Chance of precipitation in Winter
Tracy gets around 9.5 in of rain over 26 wet days across winter. The line is the day-by-day chance of measurable precipitation.
Humidity in Winter
Most of winter feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Winter
Winds average 4 mph across winter.
Sunrise & sunset in Winter
Daylight runs from about 9 h 36 min in early December to 11 hours by late February. The lit band spans sunrise to sunset each day.
Solar energy in Winter
Average shortwave solar energy reaching the ground each day across winter, about 2.7 kWh/m².
Is winter a good time to visit Tracy?
Our two travel scores rate winter for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.
winter is a reasonable time to visit Tracy for sightseeing.
What to pack for Tracy in Winter
From winter's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In winter, Tracy sees daytime highs around 58°F and nights near 42°F. Worth packing: a warm layer and rain gear. About 26 days see rain.
UV index in Tracy in Winter
Clear-sky midday UV across winter averages around 3. The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Tracy peaks around June 22 at about 10 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 15 at about 2 (moderate).
The index reaches 3 or more — the level where the WHO recommends sun protection — in 9 months of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 2 | 4 | 4 | 7 | 8 | 10 | 10 | 10 | 6 | 5 | 2 | 2 |
| Level | Moderate | Moderate | Moderate | High | Very high | Extreme | Extreme | Very high | High | High | Moderate | Moderate |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 2 | Moderate |
| Feb | 4 | Moderate |
| Mar | 4 | Moderate |
| Apr | 7 | High |
| May | 8 | Very high |
| Jun | 10 | Extreme |
| Jul | 10 | Extreme |
| Aug | 10 | Very high |
| Sep | 6 | High |
| Oct | 5 | High |
| Nov | 2 | Moderate |
| Dec | 2 | Moderate |
Air quality in Tracy in Winter
Average fine-particle pollution (PM2.5) through the year — so you can see where winter falls, not just the annual average.
Air quality in Tracy is worst in August — around 34 µg/m³ PM2.5 (moderate), about 4.9× the cleanest month (June, 7 µg/m³).
Modeled monthly averages (CAMS reanalysis, 2015–2024).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 13 | 13 | 13 | 10 | 8 | 7 | 9 | 34 | 16 | 14 | 15 | 12 |
| Level | Moderate | Moderate | Moderate | Good | Good | Good | Good | Moderate | Moderate | Moderate | Moderate | Good |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 13 | Moderate |
| Feb | 13 | Moderate |
| Mar | 13 | Moderate |
| Apr | 10 | Good |
| May | 8 | Good |
| Jun | 7 | Good |
| Jul | 9 | Good |
| Aug | 34 | Moderate |
| Sep | 16 | Moderate |
| Oct | 14 | Moderate |
| Nov | 15 | Moderate |
| Dec | 12 | Good |
Where is Tracy?
Tracy sits at 37.7°N, 121.4°W, 52 ft above sea level, in United States. The nearest listed city is Lathrop, 9.9 mi away.
Topography around Tracy
How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Tracy.
Within 2 miles, the terrain around Tracy has only modest variations in elevation — a maximum elevation change of 118 ft around an average of 52 ft above sea level; within 10 miles, significant variations in elevation — a maximum elevation change of 1,795 ft; within 50 miles, very significant variations in elevation — a maximum elevation change of 4,373 ft.
The land around Tracy is covered by artificial surfaces (64%) within 2 miles, grassland (41%) and cropland (31%) within 10 miles, and grassland (40%) and trees (24%) within 50 miles.
United States travel facts
- Power plugs
- Type A / B
- 120 V · 60 Hz
- Prices
- ≈ 100% of US
- price level, 2025
- GDP per capita
- $90,027
- 2025
- Happiness
- 6.8 / 10
- World Happiness, 2025
- Safe drinking water
- 98%
- of population, 2024
- Homicide rate
- 5.8
- per 100k, 2023
- Road deaths
- 12.7
- per 100k/yr, 2019
- Income group
- High
- World Bank
- Religion
Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.
Data sources
Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Tracy (37.7399°, -121.4262°, elevation 52 ft), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google.