Greenfield weather in September

In September, Greenfield sees average daytime highs of 83°F and overnight lows near 58°F, with 0.1 in of rain across 0.7 wet days and about 12.2 hours of daylight. It is the 3rd-warmest and 9th-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 89% 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 Greenfield's 3rd-clearest and 11th-windiest month. For the whole year in context, see Greenfield's year-round climate.

Daytime high
83°
3rd warmest
Overnight low
58°
10th coldest
Rainfall
0.1 in
0.7 wet days
Daylight
12 h 12 min
5:52 AM – 6:06 PM
Cloud cover
12%
3rd clearest
Wind
4 mph
11th windiest
Solar energy
6.31 kWh/m²
Travel score
7.9
out of 10

Greenfield is city in Monterey County, California, United States.

Density
3,107/km²
people per km²
Founded
1947

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 Greenfield reaches about 83°F in the afternoon and slips back to 58°F overnight — a 26°F spread between the day's warmth and the night's chill. On most days the high lands between 73°F and 93°F. Set against its neighbours, September runs about 4°F cooler than August and about 8°F warmer than October.

40°60°80°151015202530
Avg high (°F)Avg low (°F)
18660
28659
38659
48659
58559
68559
78559
88559
98558
108458
118458
128458
138458
148358
158357
168357
178357
188357
198357
208257
218257
228257
238257
248256
258256
268156
278156
288156
298056
308055

Greenfield weather by month

How September compares with the rest of the year at a glance. September is the 3rd-warmest and 9th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysDaylight (hours)Travel score
Jan58° / 40°3.57.69.84.5
Feb59° / 41°3.58.510.64.7
Mar63° / 43°2.67.511.75.9
Apr67° / 45°1.14.312.97.3
May74° / 50°0.52.213.98.7
Jun82° / 55°0.10.414.48.3
Jul87° / 60°0.00.314.26.4
Aug87° / 60°0.00.213.46.3
Sep83° / 58°0.10.712.27.9
Oct75° / 52°0.72.111.18.8
Nov64° / 44°1.24.210.16.8
Dec58° / 40°2.97.39.64.6

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 89% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 5% of September, with mostly cloudy or overcast conditions the remaining 6%. 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
8964
9964
10964
11964
12955
13955
14955
15955
16946
17946
18946
19946
20937
21937
22928
23928
24919
25919
26919
279010
289010
299010
309010

Chance of precipitation in September

Any precipitation

Greenfield gets around 0.1 in of rain over 0.7 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 (%)
12
22
32
42
52
62
72
82
92
102
112
122
132
142
152
162
172
182
192
202
213
223
233
243
253
263
274
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 94% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)
19181
29172
39172
49172
59172
69172
79172
89172
99361
109361
119361
129451
139451
149451
159451
169550
179640
189640
199640
209640
219640
229730
239730
249730
259730
269730
279730
289730
299730
309820

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 5:40 AM to 6:04 AM, and sunset from 6:29 PM to 5:45 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.85:406:29
212.85:416:28
312.75:426:26
412.75:436:25
512.75:446:23
612.65:446:22
712.65:456:20
812.55:466:18
912.55:476:17
1012.55:486:15
1112.45:486:14
1212.45:496:12
1312.35:506:11
1412.35:516:09
1512.35:526:08
1612.25:526:06
1712.25:536:05
1812.15:546:03
1912.15:556:01
2012.15:566:00
2112.05:575:58
2212.05:575:57
2312.05:585:55
2411.95:595:54
2511.96:005:52
2611.86:015:51
2711.86:025:49
2811.86:025:48
2911.76:035:46
3011.76:045:45

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 6.31 kWh/m².

For context, solar energy here swings from a low near 2.61 kWh/m² to a high of 8.4 kWh/m² in June across the year — September's 6.31 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
17.0Intense
27.0Intense
36.9Intense
46.9Intense
56.8Intense
66.8Intense
76.7Intense
86.7Intense
96.6Intense
106.6Intense
116.5Intense
126.5Intense
136.5Intense
146.4Intense
156.3Intense
166.3Intense
176.3Intense
186.2Intense
196.1Intense
206.1Intense
216.0Intense
226.0Bright
235.9Bright
245.9Bright
255.8Bright
265.8Bright
275.7Bright
285.7Bright
295.6Bright
305.6Bright
Planning a trip in September

Is September a good time to visit Greenfield?

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

7.9
Sightseeing
4th-best month of the year
9.1
Beach & pool
1st-best month of the year

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

What to pack for Greenfield in September

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

In September, Greenfield sees daytime highs around 83°F and nights near 58°F. Pack light clothes and sun protection.

light clothessun protection

Sea temperature near Greenfield in September

The nearest coast averages about 59°F in September — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 25 mi away) is warmest in September at about 59°F and coldest in April near 54°F.

The water stays below 68°F all year — cool enough that most swimmers want a wetsuit.

52°54°56°58°60°JanFebMarAprMayJunJulAugSepOctNovDecbracingcool
Sea temperature (°F)Comfort
Jan55Bracing
Feb55Bracing
Mar55Bracing
Apr54Bracing
May54Bracing
Jun55Bracing
Jul57Bracing
Aug59Bracing
Sep59Cool
Oct59Cool
Nov58Bracing
Dec56Bracing

UV index in Greenfield in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 7 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Greenfield peaks around June 21 at about 11 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 14 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 21UV 11Dec 14UV 2
UV index (midday)Level
Jan3Moderate
Feb4Moderate
Mar5Moderate
Apr7High
May9Very high
Jun11Extreme
Jul11Extreme
Aug10Extreme
Sep7Very high
Oct6High
Nov3Moderate
Dec2Moderate

Air quality in Greenfield 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 Greenfield is worst in September — around 27 µg/m³ PM2.5 (moderate), about 7.0× the cleanest month (December, 4 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodSep 1027 µg/m³Dec 174 µg/m³
PM2.5 (µg/m³)Level
Jan4Good
Feb5Good
Mar5Good
Apr5Good
May5Good
Jun5Good
Jul16Moderate
Aug25Moderate
Sep27Moderate
Oct6Good
Nov4Good
Dec4Good
Location & terrain

Where is Greenfield?

Greenfield sits at 36.3°N, 121.2°W, 289 ft above sea level, in United States. The nearest listed city is Soledad, 8.7 mi away.

Topography around Greenfield

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

Within 2 miles, the terrain around Greenfield has only modest variations in elevation — a maximum elevation change of 131 ft around an average of 279 ft above sea level; within 10 miles, large variations in elevation — a maximum elevation change of 3,671 ft; within 50 miles, very significant variations in elevation — a maximum elevation change of 5,883 ft.

The land around Greenfield is covered by cropland (67%) within 2 miles, grassland (53%) and cropland (22%) within 10 miles, and grassland (47%) and trees (23%) within 50 miles.

2 miles
131 ft
10 miles
3,671 ft
50 miles
5,883 ft
treesshrubsgrasslandcroplandartificial surfacesbare terrainwater
September weather nearby: Soledad 8.7 mi · Big Sur 32 mi · Salinas 34 mi · Hollister 38 mi · Seaside 39 mi · Prunedale 39 mi · Marina 40 mi · Monterey 41 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 Greenfield (36.3208°, -121.2438°, elevation 289 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. Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. 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).