Castlereagh weather in May

In May, Castlereagh sees average daytime highs of 14°C and overnight lows near 8°C, with 70 mm of precipitation across 14.1 wet days and about 15.8 hours of daylight. It is the 5th-warmest and 8th-wettest month of the year here.

Highs climb over the month, from about 13°C in the first days to 15°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 48 min at the start of May to 16 h 30 min by month's end. Set against the rest of the year, May is Castlereagh's 1st-clearest and 9th-windiest month. For the whole year in context, see Castlereagh's year-round climate.

Daytime high: 14°; 5th warmest
Overnight low: 8°; 7th coldest
Precipitation: 70 mm; 14.1 wet days
Daylight: 15 h 48 min; 4:26 AM – 8:14 PM
Cloud cover: 72%; 1st clearest
Wind: 15 km/h; 9th windiest
Solar energy: 4.95 kWh/m²
Travel score: 3.5; out of 10

Castlereagh is settlement near Belfast in Northern Ireland, UK.

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

← April Castlereagh year-round climate June →Best places to visit in May

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

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 15°C by the end.

A typical May day in Castlereagh reaches about 14°C in the afternoon and slips back to 8°C overnight — a 6°C spread between the day's warmth and the night's chill. On most days the high lands between 11°C and 17°C. Set against its neighbours, May runs about 3°C warmer than April and about 2°C cooler than June.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31
Avg high (°C)	12	12	13	13	13	13	13	13	13	13	13	13	13	13	14	14	14	14	14	14	14	14	14	15	15	15	15	15	15	15	15
Avg low (°C)	7	7	7	7	7	7	7	7	7	7	7	7	8	8	8	8	8	8	8	8	8	8	9	9	9	9	9	9	9	9	9

	Avg high (°C)	Avg low (°C)
1	12	7
2	12	7
3	13	7
4	13	7
5	13	7
6	13	7
7	13	7
8	13	7
9	13	7
10	13	7
11	13	7
12	13	7
13	13	8
14	13	8
15	14	8
16	14	8
17	14	8
18	14	8
19	14	8
20	14	8
21	14	8
22	14	8
23	14	9
24	15	9
25	15	9
26	15	9
27	15	9
28	15	9
29	15	9
30	15	9
31	15	9

How May really feels in Castlereagh

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

heat index over the day's high

Days feeling ≤ 0°C

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.

Castlereagh 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.

Month	High / Low (°C)	Rainfall (mm)	Wet days	Snow days	Daylight (hours)	Travel score
Jan	7° / 4°	77	14.2	0.8	7.6	1.0
Feb	8° / 4°	62	12.1	0.9	9.3	1.1
Mar	9° / 4°	62	13.4	0.6	11.5	1.6
Apr	11° / 6°	65	13	0.2	13.7	2.5
May	14° / 8°	70	14.1	0.1	15.8	3.5
Jun	16° / 11°	75	13.2	0	16.9	4.4
Jul	18° / 12°	81	14.6	0	16.4	4.9
Aug	18° / 12°	81	14.2	0	14.7	4.9
Sep	16° / 11°	70	12.5	0	12.5	4.4
Oct	13° / 8°	87	13.5	0	10.2	3.1
Nov	10° / 6°	85	14	0.2	8.2	1.9
Dec	8° / 4°	82	13.5	0.5	7.1	1.2

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 12% of the time in May, the clearest month of the year.

Beyond those clear spells, partly cloudy skies cover about 15% of May, with mostly cloudy or overcast conditions the remaining 72%.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31
Clearer (%)	31	31	31	32	32	33	33	33	31	31	31	30	29	28	28	28	27	26	25	25	24	24	24	24	24	24	25	25	24	24	25
Cloudier (%)	69	69	69	68	68	67	67	67	69	69	69	70	71	72	72	72	73	74	75	75	76	76	76	76	76	76	75	75	76	76	75

	Clearer (%)	Cloudier (%)
1	31	69
2	31	69
3	31	69
4	32	68
5	32	68
6	33	67
7	33	67
8	33	67
9	31	69
10	31	69
11	31	69
12	30	70
13	29	71
14	28	72
15	28	72
16	28	72
17	27	73
18	26	74
19	25	75
20	25	75
21	24	76
22	24	76
23	24	76
24	24	76
25	24	76
26	24	76
27	25	75
28	25	75
29	24	76
30	24	76
31	25	75

Chance of precipitation in May

Any precipitation

Castlereagh gets around 70 mm of rain and snow over 14.1 wet days in May. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 46% and peaks near 47% on the wettest days, and about 0 day brings snow.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31
Rain chance (%)	46	46	46	45	45	45	45	45	45	46	46	47	47	47	47	47	47	47	47	47	47	47	47	47	46	46	46	46	45	45	45

	Rain chance (%)
1	46
2	46
3	46
4	45
5	45
6	45
7	45
8	45
9	45
10	46
11	46
12	47
13	47
14	47
15	47
16	47
17	47
18	47
19	47
20	47
21	47
22	47
23	47
24	47
25	46
26	46
27	46
28	46
29	45
30	45
31	45

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 99% of days. It rarely turns muggy — the humid and sticky bands barely register.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31
Dry (%)	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	99	99	99	99	99	99	98	98	98	98	98	98	97	97	97
Comfortable (%)	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	1	1	1	1	1	1	2	2	2	2	2	2	3	3	3

	Dry (%)	Comfortable (%)
1	100	0
2	100	0
3	100	0
4	100	0
5	100	0
6	100	0
7	100	0
8	100	0
9	100	0
10	100	0
11	100	0
12	100	0
13	100	0
14	100	0
15	100	0
16	100	0
17	99	1
18	99	1
19	99	1
20	99	1
21	99	1
22	99	1
23	98	2
24	98	2
25	98	2
26	98	2
27	98	2
28	98	2
29	97	3
30	97	3
31	97	3

Wind in May

Winds average 15 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.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31
Wind speed (km/h)	15	15	15	15	15	15	15	15	15	15	15	15	15	15	15	15	15	15	15	15	15	15	14	14	14	14	14	14	14	14	14
Feels	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze	light breeze

	Wind speed (km/h)	Feels
1	15	light breeze
2	15	light breeze
3	15	light breeze
4	15	light breeze
5	15	light breeze
6	15	light breeze
7	15	light breeze
8	15	light breeze
9	15	light breeze
10	15	light breeze
11	15	light breeze
12	15	light breeze
13	15	light breeze
14	15	light breeze
15	15	light breeze
16	15	light breeze
17	15	light breeze
18	15	light breeze
19	15	light breeze
20	15	light breeze
21	15	light breeze
22	15	light breeze
23	14	light breeze
24	14	light breeze
25	14	light breeze
26	14	light breeze
27	14	light breeze
28	14	light breeze
29	14	light breeze
30	14	light breeze
31	14	light breeze

Sunrise & sunset in May

DaylightNight

Daylight runs from about 14 h 48 min at the start of May to 16 h 30 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 102 minutes over May. Sunrise moves from 4:55 AM to 4:05 AM, and sunset from 7:46 PM to 8:37 PM.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31
Daylight (h)	14.8	14.9	15.0	15.0	15.1	15.2	15.2	15.3	15.4	15.4	15.5	15.6	15.6	15.7	15.7	15.8	15.9	15.9	16.0	16.0	16.1	16.1	16.2	16.2	16.3	16.3	16.4	16.4	16.5	16.5	16.5
Sunrise (AM)	4:55	4:53	4:51	4:49	4:47	4:45	4:43	4:41	4:39	4:37	4:35	4:33	4:31	4:29	4:28	4:26	4:24	4:23	4:21	4:19	4:18	4:16	4:15	4:13	4:12	4:11	4:09	4:08	4:07	4:06	4:05
Sunset (PM)	7:46	7:48	7:50	7:52	7:54	7:55	7:57	7:59	8:01	8:03	8:05	8:07	8:08	8:10	8:12	8:14	8:15	8:17	8:19	8:20	8:22	8:24	8:25	8:27	8:28	8:30	8:31	8:33	8:34	8:36	8:37

	Daylight (h)	Sunrise (AM)	Sunset (PM)
1	14.8	4:55	7:46
2	14.9	4:53	7:48
3	15.0	4:51	7:50
4	15.0	4:49	7:52
5	15.1	4:47	7:54
6	15.2	4:45	7:55
7	15.2	4:43	7:57
8	15.3	4:41	7:59
9	15.4	4:39	8:01
10	15.4	4:37	8:03
11	15.5	4:35	8:05
12	15.6	4:33	8:07
13	15.6	4:31	8:08
14	15.7	4:29	8:10
15	15.7	4:28	8:12
16	15.8	4:26	8:14
17	15.9	4:24	8:15
18	15.9	4:23	8:17
19	16.0	4:21	8:19
20	16.0	4:19	8:20
21	16.1	4:18	8:22
22	16.1	4:16	8:24
23	16.2	4:15	8:25
24	16.2	4:13	8:27
25	16.3	4:12	8:28
26	16.3	4:11	8:30
27	16.4	4:09	8:31
28	16.4	4:08	8:33
29	16.5	4:07	8:34
30	16.5	4:06	8:36
31	16.5	4:05	8:37

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 4.95 kWh/m² — the sunniest month for solar.

For context, solar energy here swings from a low near 0.47 kWh/m² to a high of 4.95 kWh/m² in May across the year — May's 4.95 kWh/m² sits near the top of that range.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31
Solar energy (kWh/m²)	4.6	4.6	4.7	4.7	4.7	4.8	4.8	4.8	4.8	4.8	4.9	4.9	4.9	4.9	4.9	4.9	4.9	4.9	4.9	4.9	5.0	5.0	5.0	5.0	5.0	5.0	5.1	5.1	5.1	5.1	5.1
Level	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright

	Solar energy (kWh/m²)	Level
1	4.6	Bright
2	4.6	Bright
3	4.7	Bright
4	4.7	Bright
5	4.7	Bright
6	4.8	Bright
7	4.8	Bright
8	4.8	Bright
9	4.8	Bright
10	4.8	Bright
11	4.9	Bright
12	4.9	Bright
13	4.9	Bright
14	4.9	Bright
15	4.9	Bright
16	4.9	Bright
17	4.9	Bright
18	4.9	Bright
19	4.9	Bright
20	4.9	Bright
21	5.0	Bright
22	5.0	Bright
23	5.0	Bright
24	5.0	Bright
25	5.0	Bright
26	5.0	Bright
27	5.1	Bright
28	5.1	Bright
29	5.1	Bright
30	5.1	Bright
31	5.1	Bright

Planning a trip in May

Is May a good time to visit Castlereagh?

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

3.5

Sightseeing

5th-best month of the year

0.0

Beach & pool

5th-best month of the year

May is a weaker month for outdoor sightseeing in Castlereagh.

What to pack for Castlereagh in May

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

In May, Castlereagh sees daytime highs around 14°C and nights near 8°C. Pack rain gear. Worth having: a warm layer and sun protection. About 14 days see rain.

rain geara warm layersun protection

Sea temperature near Castlereagh in May

The nearest coast averages about 10°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 14°C and coldest in March near 8°C.

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

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Sea temperature (°C)	9	8	8	8	10	12	13	14	14	14	12	11
Comfort	Bracing	Bracing	Bracing	Bracing	Bracing	Bracing	Bracing	Bracing	Bracing	Bracing	Bracing	Bracing

	Sea temperature (°C)	Comfort
Jan	9	Bracing
Feb	8	Bracing
Mar	8	Bracing
Apr	8	Bracing
May	10	Bracing
Jun	12	Bracing
Jul	13	Bracing
Aug	14	Bracing
Sep	14	Bracing
Oct	14	Bracing
Nov	12	Bracing
Dec	11	Bracing

UV index in Castlereagh in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 5 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Castlereagh peaks around July 24 at about 5 (high) — a little sun protection helps at midday. It bottoms out near January 1 at about 0 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 5 months of the year.

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
UV index (midday)	0	1	2	3	5	5	5	5	3	2	1	0
Level	Low	Low	Moderate	Moderate	High	High	High	High	Moderate	Low	Low	Low

	UV index (midday)	Level
Jan	0	Low
Feb	1	Low
Mar	2	Moderate
Apr	3	Moderate
May	5	High
Jun	5	High
Jul	5	High
Aug	5	High
Sep	3	Moderate
Oct	2	Low
Nov	1	Low
Dec	0	Low

Location & terrain

Where is Castlereagh?

Castlereagh sits at 54.6°N, 5.9°W, 29 m above sea level, in United Kingdom. The nearest listed city is Belfast, 4.0 km away.

Topography around Castlereagh

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

Within 3 km, the terrain around Castlereagh has only modest variations in elevation — a maximum elevation change of 178 m around an average of 61 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 495 m; within 80 km, large variations in elevation — a maximum elevation change of 860 m.

The land around Castlereagh is covered by artificial surfaces (41%), grassland (32%) and trees (24%) within 3 km, grassland (55%) within 16 km, and water (47%) and grassland (46%) within 80 km.

3 km

178 m

artificial surfaces 41%

16 km

495 m

grassland 55%

80 km

860 m

water 47%

treesgrasslandcroplandartificial surfaceswater

← April Castlereagh year-round climate June →Best places to visit in May

May weather nearby: Belfast 4.0 km · Newtownabbey 10 km · Lisburn 11 km · Newtownards 13 km · Carrickfergus 17 km · Bangor 17 km · Antrim 26 km · Larne 31 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

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 Castlereagh (54.5735°, -5.8847°, elevation 29 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).

	Avg high (°C)	Avg low (°C)
1	12	7
2	12	7
3	13	7
4	13	7
5	13	7
6	13	7
7	13	7
8	13	7
9	13	7
10	13	7
11	13	7
12	13	7
13	13	8
14	13	8
15	14	8
16	14	8
17	14	8
18	14	8
19	14	8
20	14	8
21	14	8
22	14	8
23	14	9
24	15	9
25	15	9
26	15	9
27	15	9
28	15	9
29	15	9
30	15	9
31	15	9

	Clearer (%)	Cloudier (%)
1	31	69
2	31	69
3	31	69
4	32	68
5	32	68
6	33	67
7	33	67
8	33	67
9	31	69
10	31	69
11	31	69
12	30	70
13	29	71
14	28	72
15	28	72
16	28	72
17	27	73
18	26	74
19	25	75
20	25	75
21	24	76
22	24	76
23	24	76
24	24	76
25	24	76
26	24	76
27	25	75
28	25	75
29	24	76
30	24	76
31	25	75

	Rain chance (%)
1	46
2	46
3	46
4	45
5	45
6	45
7	45
8	45
9	45
10	46
11	46
12	47
13	47
14	47
15	47
16	47
17	47
18	47
19	47
20	47
21	47
22	47
23	47
24	47
25	46
26	46
27	46
28	46
29	45
30	45
31	45

	Dry (%)	Comfortable (%)
1	100	0
2	100	0
3	100	0
4	100	0
5	100	0
6	100	0
7	100	0
8	100	0
9	100	0
10	100	0
11	100	0
12	100	0
13	100	0
14	100	0
15	100	0
16	100	0
17	99	1
18	99	1
19	99	1
20	99	1
21	99	1
22	99	1
23	98	2
24	98	2
25	98	2
26	98	2
27	98	2
28	98	2
29	97	3
30	97	3
31	97	3

	Avg high (°C)	Avg low (°C)
1	12	7
2	12	7
3	13	7
4	13	7
5	13	7
6	13	7
7	13	7
8	13	7
9	13	7
10	13	7
11	13	7
12	13	7
13	13	8
14	13	8
15	14	8
16	14	8
17	14	8
18	14	8
19	14	8
20	14	8
21	14	8
22	14	8
23	14	9
24	15	9
25	15	9
26	15	9
27	15	9
28	15	9
29	15	9
30	15	9
31	15	9

	Clearer (%)	Cloudier (%)
1	31	69
2	31	69
3	31	69
4	32	68
5	32	68
6	33	67
7	33	67
8	33	67
9	31	69
10	31	69
11	31	69
12	30	70
13	29	71
14	28	72
15	28	72
16	28	72
17	27	73
18	26	74
19	25	75
20	25	75
21	24	76
22	24	76
23	24	76
24	24	76
25	24	76
26	24	76
27	25	75
28	25	75
29	24	76
30	24	76
31	25	75

	Rain chance (%)
1	46
2	46
3	46
4	45
5	45
6	45
7	45
8	45
9	45
10	46
11	46
12	47
13	47
14	47
15	47
16	47
17	47
18	47
19	47
20	47
21	47
22	47
23	47
24	47
25	46
26	46
27	46
28	46
29	45
30	45
31	45

	Dry (%)	Comfortable (%)
1	100	0
2	100	0
3	100	0
4	100	0
5	100	0
6	100	0
7	100	0
8	100	0
9	100	0
10	100	0
11	100	0
12	100	0
13	100	0
14	100	0
15	100	0
16	100	0
17	99	1
18	99	1
19	99	1
20	99	1
21	99	1
22	99	1
23	98	2
24	98	2
25	98	2
26	98	2
27	98	2
28	98	2
29	97	3
30	97	3
31	97	3

	Avg high (°C)	Avg low (°C)
1	12	7
2	12	7
3	13	7
4	13	7
5	13	7
6	13	7
7	13	7
8	13	7
9	13	7
10	13	7
11	13	7
12	13	7
13	13	8
14	13	8
15	14	8
16	14	8
17	14	8
18	14	8
19	14	8
20	14	8
21	14	8
22	14	8
23	14	9
24	15	9
25	15	9
26	15	9
27	15	9
28	15	9
29	15	9
30	15	9
31	15	9

	Clearer (%)	Cloudier (%)
1	31	69
2	31	69
3	31	69
4	32	68
5	32	68
6	33	67
7	33	67
8	33	67
9	31	69
10	31	69
11	31	69
12	30	70
13	29	71
14	28	72
15	28	72
16	28	72
17	27	73
18	26	74
19	25	75
20	25	75
21	24	76
22	24	76
23	24	76
24	24	76
25	24	76
26	24	76
27	25	75
28	25	75
29	24	76
30	24	76
31	25	75

	Rain chance (%)
1	46
2	46
3	46
4	45
5	45
6	45
7	45
8	45
9	45
10	46
11	46
12	47
13	47
14	47
15	47
16	47
17	47
18	47
19	47
20	47
21	47
22	47
23	47
24	47
25	46
26	46
27	46
28	46
29	45
30	45
31	45

	Dry (%)	Comfortable (%)
1	100	0
2	100	0
3	100	0
4	100	0
5	100	0
6	100	0
7	100	0
8	100	0
9	100	0
10	100	0
11	100	0
12	100	0
13	100	0
14	100	0
15	100	0
16	100	0
17	99	1
18	99	1
19	99	1
20	99	1
21	99	1
22	99	1
23	98	2
24	98	2
25	98	2
26	98	2
27	98	2
28	98	2
29	97	3
30	97	3
31	97	3