Seaford weather in September

In September, Seaford sees average daytime highs of 17°C and overnight lows near 15°C, with 68 mm of rain across 10.7 wet days and about 12.4 hours of daylight. It is the 3rd-warmest and 5th-wettest month of the year here.

Day-to-day highs hold fairly steady near 17°C through the month. The sky is clear or mostly clear about 25% of the time in September, and the air most often feels dry.

Daylight stretches from about 13 h 24 min at the start of September to 11 h 30 min by month's end. Set against the rest of the year, September is Seaford's 5th-clearest and 7th-windiest month. For the whole year in context, see Seaford's year-round climate.

Daytime high
17°
3rd warmest
Overnight low
15°
10th coldest
Rainfall
68 mm
10.7 wet days
Daylight
12 h 24 min
5:43 AM – 6:05 PM
Cloud cover
61%
5th clearest
Wind
23 km/h
7th windiest
Solar energy
3.38 kWh/m²
Travel score
5.4
out of 10

Seaford is coastal town and civil parish in East Sussex, England.

Density
1,313/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 17°C through the month.

A typical September day in Seaford reaches about 17°C in the afternoon and slips back to 15°C overnight — a 3°C spread between the day's warmth and the night's chill. On most days the high lands between 15°C and 19°C. Set against its neighbours, September runs about 1°C cooler than August and about 2°C warmer than October.

10°13°15°18°20°151015202530
Avg high (°C)Avg low (°C)
11815
21815
31815
41815
51815
61815
71815
81815
91715
101715
111715
121715
131715
141715
151715
161715
171714
181714
191714
201714
211714
221714
231714
241714
251714
261614
271614
281614
291614
301614

Seaford weather by month

How September compares with the rest of the year at a glance. September is the 3rd-warmest and 5th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / 9814.40.58.21.3
Feb / 6711.60.69.71.1
Mar / 5310.10.311.51.6
Apr10° / 489.2013.52.5
May13° / 10°478.5015.23.6
Jun15° / 13°488.7016.24.7
Jul17° / 15°508.6015.85.9
Aug18° / 16°639.1014.36.1
Sep17° / 15°6810.7012.45.4
Oct15° / 12°11414.3010.43.9
Nov12° / 12315.908.72.5
Dec / 11114.60.47.81.7

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 25% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 21% of September, with mostly cloudy or overcast conditions the remaining 54%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
14555
24654
34654
44753
54852
64753
74753
84753
94753
104654
114753
124753
134753
144753
154753
164852
174852
184753
194753
204753
214654
224654
234654
244555
254456
264456
274357
284258
294159
304060

Chance of precipitation in September

Any precipitation

Seaford gets around 68 mm of rain over 10.7 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 36% and peaks near 46% on the wettest days. The odds climb toward the end of the month.

0%20%40%60%151015202530
Rain chance (%)
129
229
329
430
530
631
732
832
933
1033
1134
1234
1334
1434
1534
1635
1735
1835
1936
2037
2137
2238
2339
2440
2541
2642
2743
2844
2945
3046

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 58% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)
1454015
2463915
3483814
4493714
5503614
6523513
7533413
8543313
9553213
10563212
11573112
12583111
13583111
14593110
1560319
1660319
1761318
1861327
1961327
2061336
2162335
2261345
2362344
2462344
2563343
2663343
2763343
2865332
2966322
3067312

Wind in September

Winds average 23 km/h in September.

Across September, daily wind ranges from about 22 km/h on the calmest days to 25 km/h at its breeziest. It stays fairly steady from day to day.

0102030151015202530
Wind speed (km/h)Feels
122breezy
222breezy
322breezy
422breezy
523breezy
623breezy
723breezy
823breezy
923breezy
1023breezy
1123breezy
1224breezy
1324breezy
1424breezy
1524breezy
1624breezy
1724breezy
1824breezy
1924breezy
2024breezy
2124breezy
2224breezy
2324breezy
2424breezy
2524breezy
2625breezy
2725breezy
2825breezy
2925breezy
3025breezy

Sunrise & sunset in September

DaylightNight

Daylight runs from about 13 h 24 min at the start of September to 11 h 30 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 114 minutes over September. Sunrise moves from 5:19 AM to 6:05 AM, and sunset from 6:40 PM to 5:33 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
113.45:196:40
213.35:206:38
313.25:226:35
413.25:236:33
513.15:256:31
613.05:276:29
713.05:286:26
812.95:306:24
912.85:316:22
1012.85:336:19
1112.75:356:17
1212.65:366:15
1312.65:386:12
1412.55:396:10
1512.45:416:08
1612.45:436:05
1712.35:446:03
1812.25:466:01
1912.25:475:58
2012.15:495:56
2112.05:515:54
2212.05:525:51
2311.95:545:49
2411.95:555:47
2511.85:575:44
2611.75:595:42
2711.76:005:40
2811.66:025:37
2911.56:045:35
3011.56:055:33

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 3.38 kWh/m².

For context, solar energy here swings from a low near 0.71 kWh/m² to a high of 5.81 kWh/m² in June across the year — September's 3.38 kWh/m² falls in the middle.

012345151015202530
Solar energy (kWh/m²)Level
14.0Bright
24.0Bright
34.0Moderate
43.9Moderate
53.9Moderate
63.8Moderate
73.8Moderate
83.7Moderate
93.7Moderate
103.6Moderate
113.6Moderate
123.5Moderate
133.5Moderate
143.4Moderate
153.4Moderate
163.4Moderate
173.3Moderate
183.3Moderate
193.2Moderate
203.2Moderate
213.1Moderate
223.1Moderate
233.0Moderate
243.0Moderate
252.9Moderate
262.9Moderate
272.8Moderate
282.8Moderate
292.7Moderate
302.7Moderate
Planning a trip in September

Hazard calendar for Seaford

In seasonPeak

In September, Seaford sits inside its rainy season season. The full year is below, with each hazard's peak months called out.

Seaford's rainy season runs August–February, when most of the year's rain falls.

Rainy season
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is September a good time to visit Seaford?

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

5.4
Sightseeing
3rd-best month of the year
1.3
Beach & pool
3rd-best month of the year

September is a reasonable time to visit Seaford for sightseeing.

What to pack for Seaford in September

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

In September, Seaford sees daytime highs around 17°C and nights near 15°C. Worth packing: rain gear and a windbreaker. About 11 days see rain.

rain geara windbreaker

Sea temperature near Seaford in September

The nearest coast averages about 17°C 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 16 km away) is warmest in August at about 17°C and coldest in March near 8°C.

The water stays below 20°C all year — cool enough that most swimmers want a wetsuit.

10°15°20°JanFebMarAprMayJunJulAugSepOctNovDecbracingcool
Sea temperature (°C)Comfort
Jan10Bracing
Feb9Bracing
Mar8Bracing
Apr9Bracing
May11Bracing
Jun13Bracing
Jul16Cool
Aug17Cool
Sep17Cool
Oct16Cool
Nov14Bracing
Dec12Bracing

UV index in Seaford in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 4 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Seaford peaks around August 10 at about 6 (high) — sunscreen and a hat are worth it in the middle of the day. It bottoms out near January 1 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 6 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighModerateLowAug 10UV 6Jan 1UV 1
UV index (midday)Level
Jan1Low
Feb1Low
Mar3Moderate
Apr4Moderate
May6High
Jun6High
Jul6High
Aug6High
Sep4Moderate
Oct2Moderate
Nov1Low
Dec1Low
Location & terrain

Where is Seaford?

Seaford sits at 50.8°N, 0.1°E, 10 m above sea level, in United Kingdom. The nearest listed city is Peacehaven, 8.0 km away.

Topography around Seaford

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Seaford.

Within 3 km, the terrain around Seaford has only modest variations in elevation — a maximum elevation change of 106 m around an average of 21 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 214 m; within 80 km, significant variations in elevation — a maximum elevation change of 302 m.

The land around Seaford is covered by water (43%) and grassland (23%) within 3 km, water (51%) and grassland (25%) within 16 km, and water (40%), grassland (23%) and trees (21%) within 80 km.

3 km
106 m
16 km
214 m
80 km
302 m
treesgrasslandcroplandartificial surfacesbare terrainwater
September weather nearby: Peacehaven 8.0 km · Rottingdean 12 km · Eastbourne 13 km · Lewes 13 km · Hailsham 15 km · Brighton 18 km · Hove 20 km · Uckfield 22 km

United Kingdom travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type D / G / M
230 V · 50 Hz
Prices
≈ 89% of US
price level, 2025
GDP per capita
$57,602
2025
Happiness
6.7 / 10
World Happiness, 2025
Safe drinking water
100%
of population, 2024
Homicide rate
1.1
per 100k, 2021
Road deaths
3.2
per 100k/yr, 2019
Income group
High
World Bank
Religion
Christian 60%none 26%Muslim 4%other 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 Seaford (50.7714°, 0.1027°, elevation 10 m), 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. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).