Trawsfynydd (Gwynedd) weather

Forecast days

Yellow weather warning.
Sunrise iconSunrise:
Sunset iconSunset:
M UV
L Pollution
No pollen data.

7 day forecast for Trawsfynydd

Today (17 September 2025)
Time
05:00
06:00
07:00
08:00
09:00
10:00
11:00
12:00
13:00
14:00
15:00
16:00
17:00
18:00
19:00
20:00
21:00
22:00
23:00
Weather symbols Heavy rain Heavy rain Heavy rain Heavy rain Heavy rain Light rain Light rain Overcast Overcast Cloudy Cloudy Sunny intervals Sunny intervals Sunny intervals Partly cloudy night Partly cloudy night Partly cloudy night Partly cloudy night Partly cloudy night
Chance of precipitation
≥95%
≥95%
≥95%
≥95%
≥95%
90%
80%
40%
20%
10%
10%
20%
10%
10%
10%
10%
10%
10%
10%
Temperature
12°
13°
14°
15°
15°
15°
16°
16°
16°
16°
16°
16°
15°
15°
14°
14°
13°
13°
13°
Feels like temperature (°C)
10°
11°
11°
11°
12°
12°
12°
12°
12°
12°
12°
12°
11°
11°
11°
11°
11°
11°
Wind direction and speed
S
16
S
20
SSW
22
SW
22
SW
22
SW
22
SW
22
WSW
22
WSW
22
SW
22
SW
22
SW
21
SW
20
SW
19
SW
17
SW
15
SW
13
SW
13
SW
12
Wind gust (mph)
40
42
42
41
41
40
38
38
39
38
38
37
35
33
31
29
28
27
27
Visibility
P
P
P
P
P
P
M
G
E
E
E
E
E
E
E
E
E
E
E
Humidity
95%
95%
96%
97%
98%
99%
100%
99%
95%
90%
87%
88%
87%
87%
88%
91%
91%
91%
92%
UV - 1 1 1 1 1 2 2 2 3 2 1 1 1 1 - - - -
Thursday (18 September 2025)
Time
00:00
01:00
02:00
03:00
04:00
05:00
06:00
07:00
08:00
09:00
10:00
11:00
12:00
13:00
14:00
15:00
16:00
17:00
18:00
19:00
20:00
21:00
22:00
23:00
Weather symbols Partly cloudy night Partly cloudy night Cloudy Light shower night Light rain Light rain Light rain Light rain Light rain Light rain Light rain Light rain Light rain Light rain Light rain Light rain Light rain Light rain Light rain Light rain Light rain Light rain Overcast Overcast
Chance of precipitation
20%
20%
40%
50%
60%
70%
70%
80%
90%
90%
90%
90%
70%
80%
70%
70%
70%
60%
60%
60%
60%
50%
50%
40%
Temperature (°C)
13°
13°
13°
13°
13°
13°
14°
14°
14°
15°
15°
15°
16°
16°
16°
16°
16°
16°
16°
16°
16°
16°
16°
16°
Feels like temperature (°C)
11°
11°
11°
11°
11°
12°
12°
12°
12°
12°
12°
12°
12°
12°
12°
13°
13°
13°
13°
13°
13°
13°
13°
13°
Wind direction and speed (mph)
SW
12
SW
11
SW
10
SW
10
SW
10
SW
11
SW
12
SW
13
SW
15
SW
17
SW
19
SW
20
SW
21
SW
22
SW
22
SW
22
SW
22
SW
22
SW
21
SW
20
SW
19
SSW
18
SSW
18
SSW
18
Wind gust (mph)
26
25
23
21
20
20
21
21
25
30
35
37
38
39
39
39
39
38
37
36
34
34
34
34
Visibility (description)
E
E
E
E
VG
G
M
M
M
M
M
M
G
G
G
G
VG
VG
VG
VG
VG
VG
VG
VG
Humidity
92%
92%
93%
93%
95%
96%
99%
99%
100%
99%
99%
99%
98%
97%
97%
97%
96%
96%
97%
97%
97%
97%
96%
95%
UV - - - - - - 1 1 1 1 1 1 2 2 2 1 1 1 1 1 - - - -
Friday (19 September 2025)
Time
00:00
01:00
02:00
03:00
04:00
05:00
06:00
07:00
08:00
09:00
10:00
11:00
12:00
13:00
14:00
15:00
16:00
17:00
18:00
19:00
20:00
21:00
22:00
23:00
Weather symbols Overcast Overcast Overcast Overcast Overcast Overcast Overcast Light rain Light rain Light rain Light rain Light rain Light rain Light rain Light rain Light rain Light rain Light rain Light rain Light rain Light rain Light rain Light rain Light rain
Chance of precipitation
30%
30%
30%
30%
40%
50%
50%
50%
60%
50%
60%
60%
60%
50%
60%
70%
80%
70%
70%
60%
60%
60%
70%
70%
Temperature (°C)
16°
16°
16°
15°
15°
15°
15°
15°
14°
15°
15°
16°
16°
16°
17°
16°
16°
16°
15°
15°
15°
14°
14°
14°
Feels like temperature (°C)
13°
13°
13°
13°
13°
13°
12°
12°
12°
12°
13°
13°
14°
14°
14°
14°
14°
14°
14°
13°
13°
13°
13°
12°
Wind direction and speed (mph)
SSW
18
SSW
17
SSW
17
SSW
17
SSW
16
SSW
16
SSW
16
SSW
16
SSW
15
SSW
15
SSW
15
SSW
15
SSW
15
SSW
15
SSW
15
SSW
15
SSW
14
SSW
13
SSW
12
SSW
11
SSW
10
SSW
10
SSW
9
SW
9
Wind gust (mph)
35
35
33
34
35
34
33
31
31
30
30
31
29
29
29
27
24
21
23
21
16
15
15
15
Visibility (description)
VG
VG
E
E
VG
VG
VG
VG
VG
VG
VG
VG
VG
VG
VG
VG
VG
VG
VG
VG
VG
VG
VG
VG
Humidity
95%
94%
93%
93%
93%
94%
95%
95%
95%
94%
93%
92%
92%
91%
90%
91%
93%
94%
95%
96%
96%
95%
95%
96%
UV - - - - - - 1 1 1 1 1 1 2 2 2 1 1 1 1 1 - - - -
Saturday (20 September 2025)
Time
00:00
01:00
02:00
03:00
04:00
05:00
06:00
07:00
08:00
09:00
10:00
11:00
12:00
13:00
14:00
15:00
16:00
17:00
18:00
19:00
20:00
21:00
22:00
23:00
Weather symbols Light rain Light rain Light rain Light rain Light rain Cloudy Light rain Light rain Light rain Light rain Light rain Light rain Light shower day Light rain Light shower day Light shower day Light shower day Light shower day Cloudy Light shower night Light shower night Light shower night Light shower night Light shower night
Chance of precipitation
60%
60%
60%
60%
50%
50%
50%
50%
50%
50%
50%
60%
60%
60%
70%
60%
60%
50%
50%
50%
60%
60%
60%
60%
Temperature (°C)
13°
13°
13°
13°
13°
12°
12°
12°
12°
12°
12°
13°
13°
13°
13°
13°
13°
13°
12°
12°
11°
11°
11°
11°
Feels like temperature (°C)
12°
12°
12°
12°
12°
11°
11°
11°
11°
11°
11°
11°
11°
11°
11°
11°
11°
11°
10°
10°
Wind direction and speed (mph)
SW
8
SW
8
SW
7
SW
6
SW
6
SW
6
SW
6
SSW
5
WSW
6
SW
7
W
9
WSW
9
WSW
10
WSW
11
W
11
W
12
W
12
WNW
12
WNW
11
W
10
W
9
W
8
W
9
WNW
9
Wind gust (mph)
13
11
13
12
11
10
10
10
12
12
12
15
17
18
19
21
21
17
17
16
16
17
15
15
Visibility (description)
G
G
G
G
G
VG
VG
VG
VG
VG
VG
VG
E
E
E
E
E
E
E
E
E
VG
VG
VG
Humidity
96%
95%
96%
95%
95%
95%
94%
94%
93%
91%
90%
88%
84%
89%
85%
85%
83%
83%
84%
87%
88%
88%
91%
91%
UV - - - - - - 1 1 1 1 1 2 2 2 2 2 1 1 1 1 - - - -
Sunday (21 September 2025)
Time
00:00
01:00
02:00
03:00
04:00
05:00
06:00
07:00
08:00
09:00
10:00
11:00
12:00
13:00
14:00
15:00
16:00
17:00
18:00
19:00
20:00
21:00
22:00
23:00
Weather symbols Light shower night Light rain Light rain Light rain Light shower night Light shower night Light shower night Light shower day Cloudy Cloudy Cloudy Cloudy Cloudy Cloudy Cloudy Cloudy Sunny intervals Sunny intervals Sunny intervals Partly cloudy night Partly cloudy night Partly cloudy night Partly cloudy night Partly cloudy night
Chance of precipitation
60%
60%
60%
60%
60%
60%
60%
50%
50%
40%
40%
40%
40%
50%
50%
50%
40%
40%
40%
40%
30%
30%
30%
20%
Temperature (°C)
10°
10°
10°
10°
10°
10°
10°
10°
11°
11°
11°
11°
11°
11°
10°
Feels like temperature (°C)
Wind direction and speed (mph)
W
9
WNW
9
NNW
9
N
9
N
10
N
10
N
10
N
10
N
10
N
11
N
12
NNE
13
NNE
13
N
13
NNE
13
N
14
NNE
13
NNE
13
NNE
12
N
10
NNE
9
NNE
8
NNE
8
NE
8
Wind gust (mph)
17
15
15
18
17
17
17
17
17
20
21
21
21
24
26
25
25
23
19
18
17
17
16
15
Visibility (description)
VG
VG
VG
VG
VG
VG
VG
VG
VG
VG
VG
VG
VG
VG
VG
VG
VG
VG
VG
VG
VG
VG
VG
VG
Humidity
91%
91%
91%
88%
89%
91%
90%
90%
89%
86%
84%
80%
77%
72%
70%
70%
71%
68%
71%
76%
80%
82%
83%
83%
UV - - - - - - - 1 1 1 2 3 3 3 3 2 2 1 1 1 - - - -
Monday (22 September 2025)
Time
00:00
01:00
04:00
07:00
10:00
13:00
16:00
19:00
22:00
Weather symbols Partly cloudy night Partly cloudy night Partly cloudy night Sunny intervals Cloudy Cloudy Sunny intervals Partly cloudy night Partly cloudy night
Chance of precipitation
20%
10%
<5%
<5%
<5%
<5%
<5%
<5%
<5%
Temperature (°C)
10°
12°
12°
Feels like temperature (°C)
Wind direction and speed (mph)
NE
7
NNE
7
NE
6
NE
6
NNE
9
NNE
11
NNE
11
NNE
8
NNE
6
Wind gust (mph)
13
9
7
10
17
18
16
9
7
Visibility (description)
VG
VG
G
G
VG
G
VG
VG
G
Humidity
84%
85%
89%
90%
69%
59%
57%
75%
88%
UV - - - 1 2 3 1 1 -
Tuesday (23 September 2025)
Time
01:00
04:00
07:00
10:00
13:00
16:00
19:00
22:00
Weather symbols Partly cloudy night Partly cloudy night Sunny intervals Sunny intervals Cloudy Sunny intervals Partly cloudy night Partly cloudy night
Chance of precipitation
<5%
<5%
<5%
10%
10%
10%
10%
<5%
Temperature (°C)
10°
12°
12°
Feels like temperature (°C)
10°
10°
Wind direction and speed (mph)
NE
5
ENE
5
ENE
5
NE
8
NE
10
NE
10
NNE
7
NE
6
Wind gust (mph)
6
6
7
15
15
13
8
6
Visibility (description)
G
G
G
VG
VG
VG
VG
G
Humidity
90%
92%
93%
73%
61%
63%
83%
92%
UV - - 1 2 4 1 1 -

UK video forecast

Trawsfynydd weather map

View the weather with our interactive map

Loading map...
WARNING
Flood alerts icon
Flood alerts in force for Wales
Flood alerts in force for Wales

Wales weather forecast

Headline:

Heavy and persistent rain.

Today:

Heaviest and most persistent rain clearing eastwards through the morning, though remaining cloudy with outbreaks of patchy rain and drizzle throughout the day, turning heavy at times over the hills. Breezy. Maximum temperature 19 °C.

Tonight:

Rain persisting throughout this evening and overnight, this turning heavy at times especially over the hills and mountains. Windy for all, especially along the coasts, and feeling humid. Minimum temperature 8 °C.

Thursday:

A cloudy, damp and mild start to Thursday. Cloud breaking in the east but drizzle persisting over the hills in the west. Staying windy. Maximum temperature 18 °C.

Outlook for Friday to Sunday:

Remaining changeable with showers or longer spells of rain at times. Some brighter periods are also likely, mainly on Friday. Temperatures close to average but turning colder later Sunday. Breezy.

Updated:

UK long range weather forecast

More from the Met Office