Tracy weather in September

In September, Tracy sees average daytime highs of 83°F and overnight lows near 57°F, with 0.1 in of rain across 0.6 wet days and about 12.3 hours of daylight. It is the 4th-warmest and 11th-wettest month of the year here.

Highs ease over the month, from about 86°F in the first days to 81°F by the end. The sky is clear or mostly clear about 87% of the time in September, and the air most often feels dry.

Daylight stretches from about 12 h 54 min at the start of September to 11 h 42 min by month's end. Set against the rest of the year, September is Tracy's 3rd-clearest and 8th-windiest month. For the whole year in context, see Tracy's year-round climate.

Daytime high
83°
4th warmest
Overnight low
57°
10th coldest
Rainfall
0.1 in
0.6 wet days
Daylight
12 h 12 min
5:53 AM – 6:07 PM
Cloud cover
13%
3rd clearest
Wind
4 mph
8th windiest
Solar energy
6.13 kWh/m²
Travel score
7.8
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 September

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 86°F in the first days to 81°F by the end.

A typical September day in Tracy reaches about 83°F in the afternoon and slips back to 57°F overnight — a 26°F spread between the day's warmth and the night's chill. On most days the high lands between 76°F and 92°F. Set against its neighbours, September runs about 4°F cooler than August and about 8°F warmer than October.

50°60°70°80°90°151015202530
Avg high (°F)Avg low (°F)
18659
28659
38659
48659
58558
68558
78558
88558
98558
108458
118458
128458
138457
148457
158357
168357
178357
188357
198357
208357
218357
228256
238256
248256
258256
268256
278156
288156
298156
308055

Tracy weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 11th-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 September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 87% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 6% of September, with mostly cloudy or overcast conditions the remaining 7%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
1973
2973
3964
4964
5964
6964
7964
8964
9955
10955
11955
12955
13955
14946
15937
16937
17937
18928
19928
20919
21919
22919
23919
249010
259010
269010
278911
288911
298812
308812

Chance of precipitation in September

Any precipitation

Tracy gets around 0.1 in of rain over 0.6 wet days in September. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 2% and peaks near 4% on the wettest days.

0%10%20%30%151015202530
Rain chance (%)
11
21
31
41
51
61
71
81
91
101
111
122
132
142
152
162
172
182
193
203
213
223
233
243
253
263
273
284
294
304

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the dry band about 81% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)
174233
275223
376213
478202
579192
679192
780182
880182
981172
1081172
1182171
1282171
1382171
1481181
1581181
1681181
1781190
1881190
1981190
2081190
2181190
2282180
2382180
2483170
2584160
2684160
2785150
2886140
2987130
3088120

Wind in September

Winds average 4 mph in September.

Across September, daily wind ranges from about 4 mph on the calmest days to 5 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202530
Wind speed (mph)Feels
15calm
25calm
35calm
45calm
55calm
65calm
75calm
85calm
95calm
105calm
115calm
125calm
135calm
145calm
155calm
165calm
175calm
185calm
194calm
204calm
214calm
224calm
234calm
244calm
254calm
264calm
274calm
284calm
294calm
304calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 12 h 54 min at the start of September to 11 h 42 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 72 minutes over September. Sunrise moves from 5:40 AM to 6:05 AM, and sunset from 6:31 PM to 5:45 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.95:406:31
212.85:416:29
312.85:426:28
412.75:426:26
512.75:436:25
612.75:446:23
712.65:456:22
812.65:466:20
912.55:476:18
1012.55:486:17
1112.45:486:15
1212.45:496:14
1312.45:506:12
1412.35:516:10
1512.35:526:09
1612.25:536:07
1712.25:546:06
1812.25:556:04
1912.15:556:02
2012.15:566:01
2112.05:575:59
2212.05:585:57
2311.95:595:56
2411.96:005:54
2511.96:015:53
2611.86:025:51
2711.86:035:49
2811.76:035:48
2911.76:045:46
3011.76:055:45

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 6.13 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 — September's 6.13 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
16.9Intense
26.8Intense
36.8Intense
46.7Intense
56.7Intense
66.6Intense
76.6Intense
86.5Intense
96.5Intense
106.4Intense
116.4Intense
126.3Intense
136.3Intense
146.2Intense
156.2Intense
166.1Intense
176.0Intense
186.0Bright
195.9Bright
205.9Bright
215.8Bright
225.8Bright
235.7Bright
245.7Bright
255.6Bright
265.5Bright
275.5Bright
285.4Bright
295.4Bright
305.3Bright
Planning a trip in September

Is September a good time to visit Tracy?

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

7.8
Sightseeing
3rd-best month of the year
9.1
Beach & pool
1st-best month of the year

September is one of the better times to visit Tracy for general sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Tracy in September

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

In September, Tracy sees daytime highs around 83°F and nights near 57°F. Pack light clothes and sun protection.

light clothessun protection

UV index in Tracy in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 6 — enough to warrant sun protection. 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 September

GoodModeratePoorUnhealthyVery unhealthy

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