Patterson weather in September

In September, Patterson sees average daytime highs of 86°F and overnight lows near 60°F, with 0.1 in of rain across 0.8 wet days and about 12.3 hours of daylight. It is the 4th-warmest and 10th-wettest month of the year here.

Highs ease over the month, from about 89°F in the first days to 83°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 48 min at the start of September to 11 h 42 min by month's end. Set against the rest of the year, September is Patterson's 3rd-clearest and 9th-windiest month. For the whole year in context, see Patterson's year-round climate.

Daytime high
86°
4th warmest
Overnight low
60°
10th coldest
Rainfall
0.1 in
0.8 wet days
Daylight
12 h 12 min
5:52 AM – 6:06 PM
Cloud cover
13%
3rd clearest
Wind
4 mph
9th windiest
Solar energy
6.14 kWh/m²
Travel score
6.7
out of 10

Patterson is city in Stanislaus County, California, United States.

Density
1,390/km²
people per km²
Founded
1909

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 89°F in the first days to 83°F by the end.

A typical September day in Patterson reaches about 86°F in the afternoon and slips back to 60°F overnight — a 26°F spread between the day's warmth and the night's chill. On most days the high lands between 77°F and 95°F. Set against its neighbours, September runs about 5°F cooler than August and about 9°F warmer than October.

60°80°100°151015202530
Avg high (°F)Avg low (°F)
19062
28962
38962
48962
58962
68962
78861
88861
98861
108761
118761
128760
138760
148660
158660
168660
178660
188560
198559
208559
218559
228559
238559
248459
258459
268458
278358
288358
298358
308258

How September really feels in Patterson

Once humidity and wind are folded in, September averages 1 day that feel above 90°F and 0 that feel at or below 32°F — the comfort signal a plain temperature reading hides.

Days feeling ≥ 90°F
1
heat index over the day's high
Days feeling ≤ 32°F
0
wind chill below the day's low

The story in September is heat — humidity pushes the afternoon "feels like" well above the raw temperature.

Patterson weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 10th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysDaylight (hours)Travel score
Jan57° / 42°3.38.89.74.2
Feb60° / 44°3.28.910.65.0
Mar65° / 46°2.68.911.76.2
Apr71° / 49°1.35.112.97.6
May79° / 55°0.73.1148.1
Jun87° / 60°0.2114.56.2
Jul92° / 64°0.00.214.34.4
Aug91° / 63°0.10.213.44.9
Sep86° / 60°0.10.812.36.7
Oct77° / 54°0.82.4118.6
Nov65° / 46°1.55.5106.6
Dec57° / 41°2.88.29.54.2

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 (%)
1964
2964
3964
4964
5964
6964
7964
8955
9955
10955
11955
12955
13955
14946
15946
16946
17937
18928
19928
20928
21928
22928
23919
249010
259010
269010
278911
288911
298911
308911

Chance of precipitation in September

Any precipitation

Patterson gets around 0.1 in of rain over 0.8 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 3% and peaks near 5% on the wettest days.

0%10%20%30%151015202530
Rain chance (%)
11
21
31
42
52
62
72
82
92
102
112
122
132
142
152
162
173
183
193
203
213
223
234
244
254
264
274
285
295
305

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 94% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)
191711
291711
392611
492611
592611
692611
792611
892611
992611
1093511
1194510
1295500
1395500
1495500
1595500
1696400
1796400
1895500
1996400
2096400
2196400
2296400
2396400
2496400
2596400
2696400
2796400
2896400
2996400
3097300

Wind in September

Winds average 4 mph in September.

Across September, 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.

0246810151015202530
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

Sunrise & sunset in September

DaylightNight

Daylight runs from about 12 h 48 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 66 minutes over September. Sunrise moves from 5:39 AM to 6:04 AM, and sunset from 6:30 PM to 5:44 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.85:396:30
212.85:406:28
312.85:416:27
412.75:416:25
512.75:426:23
612.65:436:22
712.65:446:20
812.65:456:19
912.55:466:17
1012.55:476:16
1112.45:476:14
1212.45:486:12
1312.45:496:11
1412.35:506:09
1512.35:516:08
1612.25:526:06
1712.25:536:04
1812.25:536:03
1912.15:546:01
2012.15:556:00
2112.05:565:58
2212.05:575:56
2311.95:585:55
2411.95:595:53
2511.96:005:52
2611.86:005:50
2711.86:015:48
2811.76:025:47
2911.76:035:45
3011.76:045:44

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 6.14 kWh/m².

For context, solar energy here swings from a low near 2.33 kWh/m² to a high of 8.26 kWh/m² in June across the year — September's 6.14 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
176.1Intense
186.0Intense
196.0Bright
205.9Bright
215.8Bright
225.8Bright
235.7Bright
245.7Bright
255.6Bright
265.6Bright
275.5Bright
285.5Bright
295.4Bright
305.3Bright
Planning a trip in September

Is September a good time to visit Patterson?

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

6.7
Sightseeing
4th-best month of the year
9.0
Beach & pool
1st-best month of the year

September is a reasonable time to visit Patterson for sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Patterson in September

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

In September, Patterson sees daytime highs around 86°F and nights near 60°F. Pack light clothes and sun protection.

light clothessun protection

UV index in Patterson 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 Patterson peaks around June 21 at about 10 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 17 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 highVery highHighModerateJun 21UV 10Dec 17UV 2
UV index (midday)Level
Jan2Moderate
Feb4Moderate
Mar4Moderate
Apr7High
May8Very high
Jun10Extreme
Jul10Very high
Aug10Very high
Sep6High
Oct5High
Nov2Moderate
Dec2Moderate

Air quality in Patterson 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 Patterson 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 Patterson?

Patterson sits at 37.5°N, 121.1°W, 102 ft above sea level, in United States. The nearest listed city is Ceres, 12 mi away.

Topography around Patterson

How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Patterson.

Within 2 miles, the terrain around Patterson has only modest variations in elevation — a maximum elevation change of 108 ft around an average of 105 ft above sea level; within 10 miles, large variations in elevation — a maximum elevation change of 2,142 ft; within 50 miles, very significant variations in elevation — a maximum elevation change of 4,298 ft.

The land around Patterson is covered by cropland (32%), artificial surfaces (25%) and trees (23%) within 2 miles, grassland (41%), cropland (32%) and trees (21%) within 10 miles, and grassland (46%) and trees (24%) within 50 miles.

2 miles
108 ft
10 miles
2,142 ft
50 miles
4,298 ft
treesgrasslandcroplandartificial surfacesbare terrainwater
September weather nearby: Ceres 12 mi · Modesto 14 mi · Turlock 16 mi · Ripon 19 mi · Riverbank 21 mi · Manteca 23 mi · Tracy 25 mi · Lathrop 25 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 Patterson (37.4716°, -121.1297°, elevation 102 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).