Tracy weather in January

In January, Tracy sees average daytime highs of 57°F and overnight lows near 41°F, with 3.3 in of rain across 9.1 wet days and about 9.7 hours of daylight. It is the 11th-warmest and 1st-wettest month of the year here.

Highs climb over the month, from about 56°F in the first days to 59°F by the end. The sky is clear or mostly clear about 35% of the time in January, and the air most often feels dry.

Daylight stretches from about 9 h 24 min at the start of January to 10 hours by month's end. Set against the rest of the year, January is Tracy's 12th-clearest and 11th-windiest month. For the whole year in context, see Tracy's year-round climate.

Daytime high
57°
11th warmest
Overnight low
41°
2nd coldest
Rainfall
3.3 in
9.1 wet days
Daylight
9 h 42 min
7:25 AM – 5:05 PM
Cloud cover
57%
12th clearest
Wind
4 mph
11th windiest
Solar energy
2.44 kWh/m²
Travel score
4.2
out of 10

Tracy is city in San Joaquin County, California, United States.

Density
1,509/km²
people per km²
Founded
1910

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in January

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 56°F in the first days to 59°F by the end.

A typical January day in Tracy reaches about 57°F in the afternoon and slips back to 41°F overnight — a 15°F spread between the day's warmth and the night's chill. On most days the high lands between 51°F and 63°F. Set against its neighbours, January runs on par with December and about 4°F cooler than February.

30°40°50°60°70°151015202531
Avg high (°F)Avg low (°F)
15640
25640
35640
45640
55641
65641
75641
85641
95641
105641
115641
125641
135641
145641
155741
165742
175742
185742
195742
205742
215742
225842
235842
245842
255842
265842
275842
285842
295942
305942
315942

Tracy weather by month

How January compares with the rest of the year at a glance. January is the 11th-warmest and 1st-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysDaylight (hours)Travel score
Jan57° / 41°3.39.19.74.2
Feb60° / 43°3.28.710.55.0
Mar65° / 46°2.68.911.76.2
Apr70° / 48°1.3512.97.5
May77° / 53°0.73.1148.4
Jun84° / 57°0.10.814.67.5
Jul88° / 60°0.00.214.36.2
Aug87° / 60°0.10.213.56.5
Sep83° / 57°0.10.612.37.8
Oct75° / 52°0.82.7118.6
Nov64° / 46°1.55.5106.5
Dec57° / 41°3.08.39.44.2

Cloud cover in January

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 35% of the time in January, the cloudiest month of the year.

Beyond those clear spells, partly cloudy skies cover about 12% of January, with mostly cloudy or overcast conditions the remaining 54%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14654
24555
34555
44555
54555
64456
74456
84555
94456
104555
114555
124654
134654
144654
154654
164753
174753
184753
194753
204753
214753
224753
234852
244852
254753
264852
274852
284753
294852
304852
314852

Chance of precipitation in January

Any precipitation

Tracy gets around 3.3 in of rain over 9.1 wet days in January, the wettest month. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 29% and peaks near 31% on the wettest days.

0%10%20%30%40%151015202531
Rain chance (%)
128
228
328
429
529
628
728
828
928
1028
1128
1229
1329
1429
1529
1629
1730
1830
1930
2031
2131
2231
2331
2430
2530
2630
2729
2829
2929
3028
3128

Humidity in January

DryComfortableHumidMuggyOppressiveMiserable

Most of January feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, January lands in the dry band about 100% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)
1991
2991
3991
4991
5991
6991
7991
8991
91000
101000
111000
121000
131000
141000
151000
161000
171000
181000
191000
201000
211000
221000
231000
241000
251000
261000
271000
28991
29991
30991
31991

Wind in January

Winds average 4 mph in January.

Across January, daily wind ranges from about 4 mph on the calmest days to 4 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (mph)Feels
14calm
24calm
34calm
44calm
54calm
64calm
74calm
84calm
94calm
104calm
114calm
124calm
134calm
144calm
154calm
164calm
174calm
184calm
194calm
204calm
214calm
224calm
234calm
244calm
254calm
264calm
274calm
284calm
294calm
304calm
314calm

Sunrise & sunset in January

DaylightNight

Daylight runs from about 9 h 24 min at the start of January to 10 hours by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 36 minutes over January. Sunrise moves from 7:26 AM to 7:18 AM, and sunset from 4:52 PM to 5:20 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
19.47:264:52
29.47:264:53
39.57:264:53
49.57:264:54
59.57:264:55
69.57:264:56
79.57:274:56
89.57:264:57
99.57:264:58
109.57:264:59
119.67:265:00
129.67:265:01
139.67:265:02
149.67:265:03
159.67:265:04
169.77:255:05
179.77:255:06
189.77:255:07
199.77:245:08
209.77:245:09
219.87:235:10
229.87:235:11
239.87:235:12
249.87:225:13
259.97:215:14
269.97:215:15
279.97:205:16
2810.07:205:17
2910.07:195:18
3010.07:185:19
3110.07:185:20

Solar energy in January

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in January, about 2.44 kWh/m².

For context, solar energy here swings from a low near 2.26 kWh/m² to a high of 8.27 kWh/m² in July across the year — January's 2.44 kWh/m² sits near the bottom.

0123151015202531
Solar energy (kWh/m²)Level
12.3Moderate
22.3Moderate
32.3Moderate
42.3Moderate
52.3Moderate
62.3Moderate
72.3Moderate
82.3Moderate
92.3Moderate
102.3Moderate
112.3Moderate
122.4Moderate
132.4Moderate
142.4Moderate
152.4Moderate
162.4Moderate
172.5Moderate
182.5Moderate
192.5Moderate
202.5Moderate
212.6Moderate
222.6Moderate
232.6Moderate
242.6Moderate
252.7Moderate
262.7Moderate
272.7Moderate
282.8Moderate
292.8Moderate
302.9Moderate
312.9Moderate
Planning a trip in January

Is January a good time to visit Tracy?

Our two travel scores rate January for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

4.2
Sightseeing
11th-best month of the year
0.0
Beach & pool
12th-best month of the year

January is a reasonable time to visit Tracy for sightseeing.

What to pack for Tracy in January

From January's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In January, Tracy sees daytime highs around 57°F and nights near 41°F. Worth packing: a warm layer and rain gear. About 9 days see rain.

a warm layerrain gear

UV index in Tracy in January

LowModerateHighVery highExtreme

Clear-sky midday UV in January peaks around 2. 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.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highExtremeVery highHighModerateJun 22UV 10Dec 15UV 2
UV index (midday)Level
Jan2Moderate
Feb4Moderate
Mar4Moderate
Apr7High
May8Very high
Jun10Extreme
Jul10Extreme
Aug10Very high
Sep6High
Oct5High
Nov2Moderate
Dec2Moderate

Air quality in Tracy in January

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where January 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).

010203040JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodModerateAug 1832 µg/m³Jun 157 µg/m³
PM2.5 (µg/m³)Level
Jan13Moderate
Feb13Moderate
Mar13Moderate
Apr10Good
May8Good
Jun7Good
Jul9Good
Aug34Moderate
Sep16Moderate
Oct14Moderate
Nov15Moderate
Dec12Good
Location & terrain

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.

2 miles
118 ft
10 miles
1,795 ft
50 miles
4,373 ft
treesgrasslandcroplandartificial surfacesbare terrainwaterwetland
January weather nearby: Lathrop 9.9 mi · Manteca 12 mi · Ripon 17 mi · Stockton 17 mi · Livermore 19 mi · Brentwood 20 mi · Oakley 24 mi · Modesto 24 mi

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
Protestant 47%unaffiliated 23%Roman Catholic 21%Jewish 2%

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. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).