Ashland weather in September

In September, Ashland sees average daytime highs of 79°F and overnight lows near 55°F, with 0.1 in of rain across 0.4 wet days and about 12.3 hours of daylight. It is the 3rd-warmest and 10th-wettest month of the year here.

Day-to-day highs hold fairly steady near 79°F through the month. The sky is clear or mostly clear about 86% 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 Ashland's 3rd-clearest and 8th-windiest month. For the whole year in context, see Ashland's year-round climate.

Daytime high
79°
3rd warmest
Overnight low
55°
10th coldest
Rainfall
0.1 in
0.4 wet days
Daylight
12 h 12 min
5:56 AM – 6:10 PM
Cloud cover
15%
3rd clearest
Wind
5 mph
8th windiest
Solar energy
5.96 kWh/m²
Travel score
9.0
out of 10

Ashland is census-designated place in Alameda County, California, United States.

Density
4,607/km²
people per km²

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

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 79°F through the month.

A typical September day in Ashland reaches about 79°F in the afternoon and slips back to 55°F overnight — a 24°F spread between the day's warmth and the night's chill. On most days the high lands between 71°F and 90°F. Set against its neighbours, September runs on par with August and about 6°F warmer than October.

40°60°80°151015202530
Avg high (°F)Avg low (°F)
18157
28157
38156
48056
58056
68056
78056
88056
98056
108056
118056
128056
137956
147955
157955
167955
177955
187955
197955
207955
217955
227955
237955
247955
257955
267854
277854
287854
297854
307854

Ashland weather by month

How September compares with the rest of the year at a glance. September is the 3rd-warmest and 10th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysDaylight (hours)Travel score
Jan57° / 42°3.599.74.2
Feb60° / 43°3.78.910.54.9
Mar63° / 45°2.88.411.76.0
Apr67° / 47°1.34.812.97.1
May72° / 51°0.73148.2
Jun77° / 54°0.10.914.69.1
Jul80° / 57°0.00.214.39.0
Aug80° / 57°0.10.213.59.0
Sep79° / 55°0.10.412.39.0
Oct74° / 52°0.82.9118.6
Nov64° / 46°1.65.5106.4
Dec57° / 42°3.28.79.44.2

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 86% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 7% 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
8964
9964
10964
11964
12946
13946
14946
15946
16937
17937
18937
19928
20928
219010
229010
239010
248911
258911
268812
278812
288812
298713
308713

Chance of precipitation in September

Any precipitation

Ashland gets around 0.1 in of rain over 0.4 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
121
131
141
151
161
172
182
192
202
212
222
232
242
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 72% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)
164342
265332
366322
466322
567312
668302
769292
869292
970282
1070282
1171272
1271272
1371272
1472271
1572271
1672271
1772271
1872271
1972271
2073261
2173261
2274251
2374251
2475241
2576231
2676231
2777221
2878211
2979201
3080191

Wind in September

Winds average 5 mph in September.

Across September, daily wind ranges from about 5 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
195calm
205calm
215calm
225calm
235calm
245calm
255calm
265calm
275calm
285calm
295calm
305calm

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 5:43 AM to 6:08 AM, and sunset from 6:34 PM to 5:47 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.95:436:34
212.85:436:32
312.85:446:31
412.75:456:29
512.75:466:28
612.75:476:26
712.65:486:24
812.65:496:23
912.55:506:21
1012.55:506:20
1112.45:516:18
1212.45:526:16
1312.45:536:15
1412.35:546:13
1512.35:556:12
1612.25:566:10
1712.25:566:08
1812.25:576:07
1912.15:586:05
2012.15:596:03
2112.06:006:02
2212.06:016:00
2311.96:025:59
2411.96:035:57
2511.96:045:55
2611.86:045:54
2711.86:055:52
2811.76:065:51
2911.76:075:49
3011.76:085:47

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 5.96 kWh/m².

For context, solar energy here swings from a low near 2.23 kWh/m² to a high of 8.04 kWh/m² in June across the year — September's 5.96 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
16.7Intense
26.6Intense
36.6Intense
46.5Intense
56.5Intense
66.4Intense
76.4Intense
86.3Intense
96.3Intense
106.2Intense
116.2Intense
126.1Intense
136.1Intense
146.0Intense
156.0Bright
165.9Bright
175.9Bright
185.8Bright
195.8Bright
205.7Bright
215.7Bright
225.6Bright
235.6Bright
245.5Bright
255.5Bright
265.4Bright
275.3Bright
285.3Bright
295.3Bright
305.2Bright
Planning a trip in September

Is September a good time to visit Ashland?

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

9.0
Sightseeing
2nd-best month of the year
8.6
Beach & pool
3rd-best month of the year

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

What to pack for Ashland in September

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

In September, Ashland sees daytime highs around 79°F and nights near 55°F. Worth packing: light clothes and sun protection.

light clothessun protection

Sea temperature near Ashland 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 26 mi away) is warmest in August 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
Jan54Bracing
Feb54Bracing
Mar54Bracing
Apr54Bracing
May54Bracing
Jun55Bracing
Jul57Bracing
Aug59Bracing
Sep59Bracing
Oct58Bracing
Nov56Bracing
Dec55Bracing

UV index in Ashland 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 Ashland peaks around June 23 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 23UV 10Dec 15UV 2
UV index (midday)Level
Jan2Moderate
Feb4Moderate
Mar5Moderate
Apr7High
May8Very high
Jun10Extreme
Jul10Extreme
Aug10Very high
Sep6High
Oct5High
Nov2Moderate
Dec2Moderate

Air quality in Ashland 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 Ashland is worst in August — around 25 µg/m³ PM2.5 (moderate), about 2.5× the cleanest month (June, 10 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodModerateAug 1824 µg/m³Jun 1110 µg/m³
PM2.5 (µg/m³)Level
Jan15Moderate
Feb18Moderate
Mar16Moderate
Apr12Moderate
May10Good
Jun10Good
Jul11Good
Aug25Moderate
Sep17Moderate
Oct20Moderate
Nov18Moderate
Dec13Moderate
Location & terrain

Where is Ashland?

Ashland sits at 37.7°N, 122.1°W, 46 ft above sea level, in United States. The nearest listed city is Castro Valley, 1.2 mi away.

Topography around Ashland

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

Within 2 miles, the terrain around Ashland has only modest variations in elevation — a maximum elevation change of 755 ft around an average of 141 ft above sea level; within 10 miles, large variations in elevation — a maximum elevation change of 2,031 ft; within 50 miles, very significant variations in elevation — a maximum elevation change of 4,452 ft.

The land around Ashland is covered by artificial surfaces (78%) within 2 miles, artificial surfaces (28%), water (26%) and trees (25%) within 10 miles, and water (28%), grassland (26%) and trees (25%) within 50 miles.

2 miles
755 ft
10 miles
2,031 ft
50 miles
4,452 ft
treesgrasslandcroplandartificial surfaceswaterwetland
September weather nearby: Castro Valley 1.2 mi · San Lorenzo 1.9 mi · Hayward 2.5 mi · San Leandro 3.1 mi · Union City 8.7 mi · San Ramon 9.3 mi · Alameda 9.3 mi · Moraga 9.9 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 Ashland (37.6947°, -122.1138°, elevation 46 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).