Swanley weather in May

In May, Swanley sees average daytime highs of 16°C and overnight lows near 9°C, with 50 mm of rain across 10 wet days and about 15.3 hours of daylight. It is the 5th-warmest and 8th-wettest month of the year here.

Highs climb over the month, from about 15°C in the first days to 18°C by the end. The sky is clear or mostly clear about 17% of the time in May, and the air most often feels dry.

Daylight stretches from about 14 h 30 min at the start of May to 16 hours by month's end. Set against the rest of the year, May is Swanley's 5th-clearest and 7th-windiest month. For the whole year in context, see Swanley's year-round climate.

Daytime high
16°
5th warmest
Overnight low
8th coldest
Rainfall
50 mm
10 wet days
Daylight
15 h 18 min
4:15 AM – 7:36 PM
Cloud cover
68%
5th clearest
Wind
14 km/h
7th windiest
Solar energy
5.2 kWh/m²
Travel score
4.9
out of 10

Swanley is town and civil parish in the Sevenoaks District of Kent, England.

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

Temperature in May

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 15°C in the first days to 18°C by the end.

A typical May day in Swanley reaches about 16°C in the afternoon and slips back to 9°C overnight — a 7°C spread between the day's warmth and the night's chill. On most days the high lands between 12°C and 21°C. Set against its neighbours, May runs about 3°C warmer than April and about 3°C cooler than June.

10°15°20°25°151015202531
Avg high (°C)Avg low (°C)
1157
2157
3158
4158
5158
6158
7158
8158
9158
10168
11168
12168
13168
14169
15169
16169
17169
18169
19179
20179
21179
221710
231710
241710
251710
261710
271710
281710
291810
301810
311810

How May really feels in Swanley

Once humidity and wind are folded in, May averages 0 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

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

May sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Swanley weather by month

How May compares with the rest of the year at a glance. May is the 5th-warmest and 8th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / 5110.80.78.11.0
Feb / 439.219.61.2
Mar10° / 409.70.611.52.3
Apr13° / 4610.80.113.53.5
May16° / 5010015.34.9
Jun19° / 12°539.7016.36.0
Jul21° / 14°5310.2015.96.4
Aug21° / 14°609.9014.46.4
Sep18° / 12°458.7012.45.9
Oct15° / 5610.5010.44.2
Nov11° / 5810.70.18.62.4
Dec / 56110.87.71.2

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 17% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 16% of May, with mostly cloudy or overcast conditions the remaining 67%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
13268
23268
33367
43367
53367
63367
73367
83367
93466
103466
113466
123268
133268
143268
153268
163268
173268
183268
193169
203169
213268
223169
233169
243169
253268
263268
273268
283268
293169
303268
313268

Chance of precipitation in May

Any precipitation

Swanley gets around 50 mm of rain over 10 wet days in May. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 33% and peaks near 36% on the wettest days.

0%10%20%30%40%50%151015202531
Rain chance (%)
136
235
334
434
533
632
731
831
931
1031
1131
1232
1332
1432
1533
1633
1733
1833
1934
2034
2134
2234
2334
2434
2534
2634
2734
2834
2934
3034
3134

Humidity in May

DryComfortableHumidMuggyOppressiveMiserable

Most of May feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, May lands in the dry band about 95% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)
19910
29910
39910
49910
59910
69820
79820
89820
99820
109730
119730
129730
139730
149730
159640
169640
179640
189640
199550
209550
219460
229460
239370
249370
259280
269190
279190
2890100
2988111
3087121
3187121

Wind in May

Winds average 14 km/h in May.

Across May, daily wind ranges from about 14 km/h on the calmest days to 15 km/h at its breeziest. It stays fairly steady from day to day.

05101520151015202531
Wind speed (km/h)Feels
115light breeze
215light breeze
315light breeze
415light breeze
515light breeze
615light breeze
715light breeze
815light breeze
915light breeze
1015light breeze
1115light breeze
1215light breeze
1315light breeze
1415light breeze
1514light breeze
1614light breeze
1714light breeze
1814light breeze
1914light breeze
2014light breeze
2114light breeze
2214light breeze
2314light breeze
2414light breeze
2514light breeze
2614light breeze
2714light breeze
2814light breeze
2914light breeze
3014light breeze
3114light breeze

Sunrise & sunset in May

DaylightNight

Daylight runs from about 14 h 30 min at the start of May to 16 hours by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 90 minutes over May. Sunrise moves from 4:41 AM to 3:57 AM, and sunset from 7:12 PM to 7:56 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
114.54:417:12
214.64:397:14
314.64:377:15
414.74:357:17
514.84:337:19
614.84:327:20
714.94:307:22
814.94:287:24
915.04:267:25
1015.04:257:27
1115.14:237:28
1215.14:217:30
1315.24:207:31
1415.24:187:33
1515.34:177:35
1615.34:157:36
1715.44:147:38
1815.44:127:39
1915.54:117:40
2015.54:097:42
2115.64:087:43
2215.64:077:45
2315.74:067:46
2415.74:047:48
2515.84:037:49
2615.84:027:50
2715.84:017:51
2815.94:007:53
2915.93:597:54
3016.03:587:55
3116.03:577:56

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.2 kWh/m².

For context, solar energy here swings from a low near 0.66 kWh/m² to a high of 5.47 kWh/m² in June across the year — May's 5.2 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
14.9Bright
24.9Bright
34.9Bright
45.0Bright
55.0Bright
65.0Bright
75.0Bright
85.1Bright
95.1Bright
105.1Bright
115.1Bright
125.2Bright
135.2Bright
145.2Bright
155.2Bright
165.2Bright
175.2Bright
185.2Bright
195.2Bright
205.2Bright
215.2Bright
225.2Bright
235.3Bright
245.3Bright
255.3Bright
265.3Bright
275.3Bright
285.3Bright
295.3Bright
305.3Bright
315.3Bright
Planning a trip in May

Is May a good time to visit Swanley?

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

4.9
Sightseeing
5th-best month of the year
0.8
Beach & pool
5th-best month of the year

May is a reasonable time to visit Swanley for sightseeing.

What to pack for Swanley in May

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

In May, Swanley sees daytime highs around 16°C and nights near 9°C. Worth packing: a warm layer, rain gear and sun protection. About 10 days see rain.

a warm layerrain gearsun protection

Sea temperature near Swanley in May

The nearest coast averages about 11°C in May — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 66 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.

5°10°15°20°JanFebMarAprMayJunJulAugSepOctNovDecbracingcool
Sea temperature (°C)Comfort
Jan9Bracing
Feb8Bracing
Mar8Bracing
Apr9Bracing
May11Bracing
Jun13Bracing
Jul16Cool
Aug17Cool
Sep17Cool
Oct16Cool
Nov14Bracing
Dec11Bracing

UV index in Swanley in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May 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 Swanley peaks around July 24 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.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighModerateLowJul 24UV 6Jan 1UV 1
UV index (midday)Level
Jan1Low
Feb1Low
Mar3Moderate
Apr4Moderate
May6High
Jun6High
Jul6High
Aug6High
Sep4Moderate
Oct2Moderate
Nov1Low
Dec1Low
Location & terrain

Where is Swanley?

Swanley sits at 51.4°N, 0.2°E, 81 m above sea level, in United Kingdom. The nearest listed city is Bexley, 5.0 km away.

Topography around Swanley

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

Within 3 km, the terrain around Swanley has only modest variations in elevation — a maximum elevation change of 107 m around an average of 72 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 258 m; within 80 km, significant variations in elevation — a maximum elevation change of 303 m.

The land around Swanley is covered by grassland (33%), trees (31%) and cropland (23%) within 3 km, trees (35%), grassland (25%) and artificial surfaces (24%) within 16 km, and grassland (27%), trees (25%) and cropland (24%) within 80 km.

3 km
107 m
16 km
258 m
80 km
303 m
treesgrasslandcroplandartificial surfaceswater
May weather nearby: Bexley 5.0 km · Orpington 6.0 km · Dartford 6.0 km · Chislehurst 8.0 km · Welling 9.0 km · Longfield 9.0 km · Hartley 9.0 km · Eltham 10 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 Swanley (51.3972°, 0.1732°, elevation 81 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).