Casa Grande weather in September

In September, Casa Grande sees average daytime highs of 99°F and overnight lows near 74°F, with 0.9 in of rain across 3.1 wet days and about 12.2 hours of daylight. It is the 4th-warmest and 5th-wettest month of the year here.

Highs ease over the month, from about 101°F in the first days to 96°F by the end. The sky is clear or mostly clear about 80% of the time in September, and the air most often feels dry.

Daylight stretches from about 12 h 42 min at the start of September to 11 h 42 min by month's end. Set against the rest of the year, September is Casa Grande's 4th-clearest and 8th-windiest month. For the whole year in context, see Casa Grande's year-round climate.

Daytime high
99°
4th warmest
Overnight low
74°
10th coldest
Rainfall
0.9 in
3.1 wet days
Daylight
12 h 12 min
6:15 AM – 6:27 PM
Cloud cover
23%
4th clearest
Wind
5 mph
8th windiest
Solar energy
6.13 kWh/m²
Travel score
1.8
out of 10

Casa Grande is city in Pinal County, Arizona, United States.

Density
180/km²
people per km²
Founded
1879

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 101°F in the first days to 96°F by the end.

A typical September day in Casa Grande reaches about 99°F in the afternoon and slips back to 74°F overnight — a 24°F spread between the day's warmth and the night's chill. On most days the high lands between 91°F and 106°F. Set against its neighbours, September runs about 5°F cooler than August and about 10°F warmer than October.

60°80°100°151015202530
Avg high (°F)Avg low (°F)
110279
210278
310178
410178
510178
610178
710177
810177
910077
1010076
1110076
1210076
1310076
149975
159975
169974
179974
189974
199874
209873
219873
229873
239872
249772
259771
269771
279671
289670
299670
309569

How September really feels in Casa Grande

Once humidity and wind are folded in, September averages 30 days 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
30
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.

Casa Grande weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 5th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysDaylight (hours)Travel score
Jan67° / 43°1.03.510.17.5
Feb71° / 47°1.13.710.87.8
Mar78° / 52°0.72.711.88.3
Apr85° / 57°0.21.112.86.8
May94° / 65°0.10.613.73.5
Jun104° / 74°0.10.514.10.4
Jul105° / 81°0.83.913.90.0
Aug103° / 81°1.14.313.20.2
Sep99° / 74°0.93.112.21.8
Oct89° / 63°0.52.111.25.5
Nov76° / 51°0.51.810.38.6
Dec66° / 43°0.93.69.97.4

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 80% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 9% of September, with mostly cloudy or overcast conditions the remaining 11%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
18614
28614
38614
48614
58713
68812
78812
88812
98911
108911
119010
129010
13919
14919
15919
169010
17919
18919
19919
20919
21919
22919
239010
249010
258911
268911
278911
288911
298911
308911

Chance of precipitation in September

Any precipitation

Casa Grande gets around 0.9 in of rain over 3.1 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 11% and peaks near 15% on the wettest days. The odds ease toward the end of the month.

0%10%20%30%151015202530
Rain chance (%)
115
215
315
415
515
614
714
814
913
1013
1113
1212
1312
1412
1511
1611
1710
1810
199
209
218
228
237
247
257
267
277
287
297
307

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 57% of days. Sticky, muggy-or-worse air turns up on roughly 12% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1312124185
2322124175
3332224175
4342223165
5362223154
6372223144
7392222134
8412222133
9432121123
10452120113
11472020103
12491919103
13511918103
1454181792
1556171692
1659161582
1762151382
1863151282
1966141172
2067131172
2169131062
227112962
237212862
247411852
257610752
267610752
277910641
28809641
29819631
30819631

Wind in September

Winds average 5 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
14calm
24calm
34calm
44calm
54calm
64calm
74calm
84calm
95calm
105calm
115calm
125calm
135calm
145calm
155calm
165calm
175calm
185calm
195calm
205calm
215calm
225calm
235calm
245calm
255calm
265calm
275calm
285calm
295calm
305calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 12 h 42 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 60 minutes over September. Sunrise moves from 6:05 AM to 6:25 AM, and sunset from 6:48 PM to 6:08 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.76:056:48
212.76:066:47
312.66:076:45
412.66:076:44
512.66:086:43
612.56:096:41
712.56:096:40
812.56:106:39
912.46:116:37
1012.46:116:36
1112.46:126:34
1212.36:136:33
1312.36:136:32
1412.36:146:30
1512.26:156:29
1612.26:156:27
1712.26:166:26
1812.16:176:25
1912.16:176:23
2012.16:186:22
2112.06:196:20
2212.06:196:19
2312.06:206:17
2411.96:216:16
2511.96:216:15
2611.96:226:13
2711.86:236:12
2811.86:246:10
2911.76:246:09
3011.76:256:08

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 3.25 kWh/m² to a high of 8.47 kWh/m² in June across the year — September's 6.13 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
16.5Intense
26.4Intense
36.4Intense
46.4Intense
56.4Intense
66.3Intense
76.3Intense
86.3Intense
96.3Intense
106.3Intense
116.2Intense
126.2Intense
136.2Intense
146.2Intense
156.1Intense
166.1Intense
176.1Intense
186.1Intense
196.0Intense
206.0Intense
216.0Intense
226.0Bright
235.9Bright
245.9Bright
255.9Bright
265.9Bright
275.8Bright
285.8Bright
295.8Bright
305.7Bright
Planning a trip in September

Is September a good time to visit Casa Grande?

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

1.8
Sightseeing
9th-best month of the year
5.1
Beach & pool
7th-best month of the year

September is a weaker month for outdoor sightseeing in Casa Grande.

What to pack for Casa Grande in September

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

In September, Casa Grande sees daytime highs around 99°F and nights near 74°F. Pack light clothes and sun protection. About 3 days see rain.

light clothessun protection

UV index in Casa Grande in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 9 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Casa Grande peaks around June 23 at about 11 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 20 at about 3 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateVery highExtremeVery highHighModerateJun 23UV 11Dec 20UV 3
UV index (midday)Level
Jan4Moderate
Feb5Moderate
Mar5Moderate
Apr8Very high
May9Very high
Jun11Extreme
Jul11Extreme
Aug11Extreme
Sep9Very high
Oct7High
Nov5Moderate
Dec3Moderate

Air quality in Casa Grande 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 Casa Grande is worst in June — around 28 µg/m³ PM2.5 (moderate), about 2.2× the cleanest month (October, 12 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateJun 1626 µg/m³Oct 1212 µg/m³
PM2.5 (µg/m³)Level
Jan13Moderate
Feb13Moderate
Mar14Moderate
Apr14Moderate
May14Moderate
Jun28Moderate
Jul14Moderate
Aug13Moderate
Sep13Moderate
Oct12Moderate
Nov13Moderate
Dec13Moderate
Location & terrain

Where is Casa Grande?

Casa Grande sits at 32.9°N, 111.8°W, 1,398 ft above sea level, in United States. The nearest listed city is Eloy, 14 mi away.

Topography around Casa Grande

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

Within 2 miles, the terrain around Casa Grande has only modest variations in elevation — a maximum elevation change of 102 ft around an average of 1,398 ft above sea level; within 10 miles, large variations in elevation — a maximum elevation change of 2,182 ft; within 50 miles, very significant variations in elevation — a maximum elevation change of 4,928 ft.

The land around Casa Grande is covered by bare terrain (44%) and artificial surfaces (38%) within 2 miles, bare terrain (43%) and shrubs (25%) within 10 miles, and shrubs (59%) and bare terrain (20%) within 50 miles.

2 miles
102 ft
10 miles
2,182 ft
50 miles
4,928 ft
treesshrubsgrasslandcroplandartificial surfacesbare terrain
September weather nearby: Eloy 14 mi · Maricopa 21 mi · Florence 24 mi · San Tan Valley 25 mi · Queen Creek 27 mi · Chandler 30 mi · Gilbert 33 mi · Ahwatukee Foothills 35 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 Casa Grande (32.8795°, -111.7574°, elevation 1,398 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).