Gelligaer weather in May

In May, Gelligaer sees average daytime highs of 15°C and overnight lows near 7°C, with 89 mm of rain across 13.6 wet days and about 15.3 hours of daylight. It is the 5th-warmest and 6th-wettest month of the year here.

Highs climb over the month, from about 13°C in the first days to 16°C by the end. The sky is clear or mostly clear about 12% 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 Gelligaer's 3rd-clearest and 8th-windiest month. For the whole year in context, see Gelligaer's year-round climate.

Daytime high
15°
5th warmest
Overnight low
8th coldest
Rainfall
89 mm
13.6 wet days
Daylight
15 h 24 min
4:28 AM – 7:51 PM
Cloud cover
72%
3rd clearest
Wind
14 km/h
8th windiest
Solar energy
5 kWh/m²
Travel score
3.9
out of 10

Gelligaer is town in Caerphilly County Borough, Wales, UK.

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 13°C in the first days to 16°C by the end.

A typical May day in Gelligaer reaches about 15°C in the afternoon and slips back to 7°C overnight — a 8°C spread between the day's warmth and the night's chill. On most days the high lands between 11°C and 20°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)
1136
2136
3136
4136
5146
6146
7146
8146
9146
10146
11147
12147
13147
14147
15157
16157
17157
18157
19157
20158
21158
22158
23158
24168
25168
26168
27168
28168
29168
30169
31169

How May really feels in Gelligaer

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.

Gelligaer weather by month

How May compares with the rest of the year at a glance. May is the 5th-warmest and 6th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / 10014.61.78.10.5
Feb / 8011.41.99.60.7
Mar / 7612.71.411.51.6
Apr12° / 8012.90.513.62.8
May15° / 8913.6015.33.9
Jun17° / 10°8312.2016.35.0
Jul19° / 12°8413015.95.6
Aug19° / 12°9012.6014.45.5
Sep16° / 10°7711.2012.44.8
Oct13° / 11113.60.110.43.1
Nov / 10313.90.68.61.7
Dec / 10813.31.67.70.7

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 12% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 15% of May, with mostly cloudy or overcast conditions the remaining 73%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
12971
22971
32872
42872
52971
62971
72971
82872
92872
102872
112872
122773
132773
142773
152674
162575
172674
182575
192575
202575
212575
222476
232575
242575
252575
262575
272773
282773
292773
302872
312872

Chance of precipitation in May

Any precipitation

Gelligaer gets around 89 mm of rain over 13.6 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 45% and peaks near 46% on the wettest days.

0%20%40%60%151015202531
Rain chance (%)
144
244
344
444
544
644
744
844
944
1044
1145
1245
1346
1446
1546
1646
1746
1845
1945
2045
2145
2245
2345
2445
2545
2645
2745
2845
2945
3045
3145

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 97% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)
11000
21000
3991
4991
5991
6991
7991
8991
9982
10982
11982
12982
13982
14982
15982
16982
17973
18973
19973
20973
21973
22964
23964
24964
25964
26964
27955
28955
29955
30946
31946

Wind in May

Winds average 14 km/h in May.

Across May, daily wind ranges from about 13 km/h on the calmest days to 14 km/h at its breeziest. It stays fairly steady from day to day.

05101520151015202531
Wind speed (km/h)Feels
114light breeze
214light breeze
314light breeze
414light breeze
514light breeze
614light breeze
714light breeze
814light breeze
914light breeze
1014light breeze
1114light breeze
1214light breeze
1314light breeze
1414light breeze
1514light breeze
1614light breeze
1714light breeze
1813light breeze
1913light breeze
2013light breeze
2113light breeze
2213light breeze
2313light breeze
2413light breeze
2513light breeze
2613light breeze
2713light breeze
2813light breeze
2913light breeze
3013light breeze
3113light 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 4:54 AM to 4:10 AM, and sunset from 7:27 PM to 8:11 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
114.54:547:27
214.64:527:28
314.74:507:30
414.74:487:32
514.84:467:33
614.84:447:35
714.94:437:37
815.04:417:38
915.04:397:40
1015.14:377:41
1115.14:367:43
1215.24:347:45
1315.24:327:46
1415.34:317:48
1515.34:297:49
1615.44:287:51
1715.44:267:52
1815.54:257:54
1915.54:237:55
2015.64:227:57
2115.64:217:58
2215.74:198:00
2315.74:188:01
2415.84:178:02
2515.84:168:04
2615.84:158:05
2715.94:138:06
2815.94:128:08
2916.04:118:09
3016.04:108:10
3116.04:108:11

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5 kWh/m².

For context, solar energy here swings from a low near 0.63 kWh/m² to a high of 5.27 kWh/m² in June across the year — May's 5 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
14.7Bright
24.7Bright
34.8Bright
44.8Bright
54.8Bright
64.9Bright
74.9Bright
84.9Bright
94.9Bright
104.9Bright
115.0Bright
125.0Bright
135.0Bright
145.0Bright
155.0Bright
165.0Bright
175.0Bright
185.0Bright
195.0Bright
205.0Bright
215.0Bright
225.0Bright
235.0Bright
245.0Bright
255.0Bright
265.0Bright
275.0Bright
285.1Bright
295.1Bright
305.1Bright
315.1Bright
Planning a trip in May

Is May a good time to visit Gelligaer?

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

3.9
Sightseeing
5th-best month of the year
0.2
Beach & pool
5th-best month of the year

May is a weaker month for outdoor sightseeing in Gelligaer.

What to pack for Gelligaer in May

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

In May, Gelligaer sees daytime highs around 15°C and nights near 7°C. Worth packing: a warm layer, rain gear and sun protection. About 14 days see rain.

a warm layerrain gearsun protection

Sea temperature near Gelligaer in May

The nearest coast averages about 12°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 33 km away) is warmest in August at about 18°C and coldest in February near 7°C.

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

5°10°15°20°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshing
Sea temperature (°C)Comfort
Jan8Bracing
Feb7Bracing
Mar8Bracing
Apr9Bracing
May12Bracing
Jun15Bracing
Jul17Cool
Aug18Cool
Sep17Cool
Oct15Bracing
Nov12Bracing
Dec9Bracing

UV index in Gelligaer 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 Gelligaer peaks around August 13 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 13UV 6Jan 1UV 1
UV index (midday)Level
Jan1Low
Feb1Low
Mar3Moderate
Apr4Moderate
May6High
Jun6High
Jul6High
Aug7High
Sep4Moderate
Oct2Moderate
Nov1Low
Dec1Low
Location & terrain

Where is Gelligaer?

Gelligaer sits at 51.7°N, 3.3°W, 233 m above sea level, in United Kingdom. The nearest listed city is Blackwood, 3.0 km away.

Topography around Gelligaer

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

Within 3 km, the terrain around Gelligaer has significant variations in elevation — a maximum elevation change of 262 m around an average of 205 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 554 m; within 80 km, large variations in elevation — a maximum elevation change of 864 m.

The land around Gelligaer is covered by grassland (46%) and trees (36%) within 3 km, grassland (46%) and trees (42%) within 16 km, and grassland (52%) within 80 km.

3 km
262 m
16 km
554 m
80 km
864 m
treesgrasslandcroplandartificial surfaceswater
May weather nearby: Blackwood 3.0 km · Pontypridd 9.0 km · Caerphilly 10 km · Risca 12 km · Merthyr Tydfil 13 km · Ebbw Vale 13 km · Rhondda 13 km · Aberdare 14 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 Gelligaer (51.6644°, -3.2561°, elevation 233 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).