17.05
sun
sun
Day
52°F
NE 13 mph
Precip.
100%
100%
Night
41°F
NE 5 mph
Precip.
83%
83%
18.05
mon
mon
Day
54°F
NW 6 mph
Precip.
72%
72%
Night
46°F
NW 12 mph
Precip.
0%
0%
19.05
tue
tue
Day
52°F
NE 9 mph
Precip.
100%
100%
Night
52°F
NE 11 mph
Precip.
89%
89%
20.05
wed
wed
Day
55°F
NE 17 mph
Precip.
84%
84%
Night
55°F
NE 9 mph
Precip.
78%
78%
21.05
thu
thu
Day
64°F
NE 13 mph
Precip.
100%
100%
Night
55°F
NE 5 mph
Precip.
100%
100%
22.05
fri
fri
Day
63°F
NW 11 mph
Precip.
100%
100%
Night
57°F
NE 2 mph
Precip.
0%
0%
23.05
sat
sat
Day
66°F
SW 4 mph
Precip.
59%
59%
Night
54°F
NE 3 mph
Precip.
0%
0%
24.05
sun
sun
Day
64°F
W 9 mph
Precip.
0%
0%
Night
54°F
W 5 mph
Precip.
0%
0%
25.05
mon
mon
Day
61°F
W 10 mph
Precip.
0%
0%
Night
50°F
W 9 mph
Precip.
0%
0%
26.05
tue
tue
Day
57°F
NW 14 mph
Precip.
0%
0%
Night
54°F
NW 11 mph
Precip.
48%
48%
27.05
wed
wed
Day
59°F
NW 12 mph
Precip.
0%
0%
Night
50°F
W 4 mph
Precip.
0%
0%
28.05
thu
thu
Day
61°F
NW 7 mph
Precip.
100%
100%
Night
52°F
NE 4 mph
Precip.
100%
100%
29.05
fri
fri
Day
57°F
E 11 mph
Precip.
100%
100%
Night
45°F
E 13 mph
Precip.
0%
0%
30.05
sat
sat
Day
50°F
E 17 mph
Precip.
100%
100%
Night
50°F
E 19 mph
Precip.
21%
21%
Sea water temperature in May, °F
Show year:
2026
2025
2024
The average sea water temperature in May of 2026 was 52.9°F. The highest and lowest sea temperatures during the month were 53.4°F and 52.2°F.
Air temperature in Belfast, °F
Precipitation total in Belfast, in.
* Charts above show average data for the last 3 years.
Best time for vacation in Belfast
Belfast on a weather map
Places in United Kingdom:
Name
°F
24 Hours Forecast
Belfast
Local time: 08:00
May 17, sunday
0900
46°F
NE
12 mph
12 mph
1200
52°F
NE
13 mph
13 mph
1500
50°F
NE
12 mph
12 mph
1800
50°F
NE
10 mph
10 mph
2100
43°F
NE
6 mph
6 mph
May 18, monday
0000
41°F
NE
5 mph
5 mph
0300
37°F
E
4 mph
4 mph
0600
36°F
E
3 mph
3 mph
