Dolgellau is among the wettest of UK towns: 1,755 mm (69 in) of rain a year
In January the night’s low is typically 2.6°C (37°F). Winters are mild: January nights here are milder than in 87% of UK towns. The gap between a January night and a July afternoon is 17°C. The heating season runs November to April: each of those months averages under 10°C.
Met Office 1991–2020 averages for the town itself.
A year in Dolgellau at a glance
Each month’s typical high and low, in °C.
What a year in Dolgellau feels like
Typical highs and lows by season and by month, from the Met Office’s 1991–2020 averages.
About 1,755 mm of rain a year
January is the wettest month and April the driest. About 63 days a year bring 10 mm (0.4 in) or more. 3rd wettest of 13 Gwynedd towns of 2,500+.
Rain by month
Millimetres
Sunshine by month
Hours of bright sunshine at Valley (Anglesey)
40 air frosts and 8 days of 25°C a year
On about 40 nights a year the air drops below freezing; days that stay below freezing are rare. About 8 days a year reach 25°C (77°F).
Day counts are 1991–2020 averages from the Met Office’s 2 km grid. The Met Office calls a day of 25°C or more a summer day and a night below 0°C an air frost; ground frosts, on grass, come more often.
The Met Office station at Valley (Anglesey)
Valley (Anglesey) is 44 miles north-west of Dolgellau, 10 m (33 ft) above sea level. It is the nearest of the 37 long-running stations the Met Office publishes in full; at that distance read it for sunshine and the station’s own record, not as the town’s figures.
| Month | High | Low | Rain | Air frosts | Sun (hours) |
|---|---|---|---|---|---|
| January | 8.4°C | 3.8°C | 75 mm | 5.2 | 58 |
| February | 8.4°C | 3.6°C | 62 mm | 4.8 | 81 |
| March | 9.8°C | 4.5°C | 57 mm | 2.4 | 126 |
| April | 12.1°C | 6.1°C | 54 mm | 0.5 | 173 |
| May | 15.0°C | 8.6°C | 52 mm | 0.0 | 219 |
| June | 17.2°C | 11.0°C | 57 mm | 0.0 | 203 |
| July | 18.8°C | 12.9°C | 58 mm | 0.0 | 190 |
| August | 18.8°C | 13.1°C | 69 mm | 0.0 | 176 |
| September | 17.3°C | 11.6°C | 74 mm | 0.0 | 143 |
| October | 14.3°C | 9.2°C | 102 mm | 0.1 | 101 |
| November | 11.3°C | 6.6°C | 104 mm | 0.7 | 59 |
| December | 9.1°C | 4.4°C | 94 mm | 4.2 | 46 |
| Year | 13.4°C | 8.0°C | 857 mm | 18 | 1,575 |
Met Office historic station data, Valley, 1991–2020 months averaged (a month needs 20 of the 30 years; estimated values counted, missing months left out). Sunshine: Kipp & Zonen recorder.
How Dolgellau compares
Against the 2,537 towns and cities of 2,500 or more across the UK, each with its own Met Office averages, and its place among Gwynedd towns that size.
Nearby towns’ climate
The nearest towns of 1,000+ within 12 miles: a hill, a valley or the sea can make a real difference over a few miles.
| Town | July high | January low | Rain a year |
|---|---|---|---|
| Dolgellau | 19.7°C | 2.6°C | 1,755 mm |
| Barmouth 7.4 mi | 20.1°C about the same | 3.3°C 0.7°C milder | 1,046 mm |
| Machynlleth 10.5 mi | 19.2°C 0.5°C cooler | 2.5°C about the same | 2,132 mm |
Dolgellau weather by month
Average daily high and low, mean temperature and rain, 1991–2020, for the town itself (the Met Office’s HadUK-Grid).
| Month | High | Low | Mean | Rain |
|---|---|---|---|---|
| January | 7.7°C 46°F | 2.6°C 37°F | 5.1°C | 210 mm 8.3 in |
| February | 7.8°C 46°F | 2.2°C 36°F | 5.0°C | 142 mm 5.6 in |
| March | 9.8°C 50°F | 3.2°C 38°F | 6.5°C | 125 mm 4.9 in |
| April | 12.8°C 55°F | 5.0°C 41°F | 8.8°C | 96 mm 3.8 in |
| May | 15.9°C 61°F | 7.6°C 46°F | 11.6°C | 99 mm 3.9 in |
| June | 18.3°C 65°F | 10.2°C 50°F | 14.1°C | 107 mm 4.2 in |
| July | 19.7°C 67°F | 12.2°C 54°F | 15.8°C | 122 mm 4.8 in |
| August | 19.2°C 67°F | 12.0°C 54°F | 15.6°C | 128 mm 5.1 in |
| September | 17.1°C 63°F | 10.0°C 50°F | 13.5°C | 142 mm 5.6 in |
| October | 13.6°C 56°F | 7.6°C 46°F | 10.5°C | 186 mm 7.3 in |
| November | 10.2°C 50°F | 4.9°C 41°F | 7.5°C | 193 mm 7.6 in |
| December | 7.9°C 46°F | 2.7°C 37°F | 5.3°C | 206 mm 8.1 in |
| Year | 13.3°C | 6.7°C | 9.9°C | 1,755 mm |
Where Dolgellau’s numbers come from
Averages over 30 years, not a forecast.
- Mean temperature, rain and day counts: HadUK-Grid 1991–2020 averages for the 1 Met Office 2 km grid square whose centre lies inside Dolgellau’s built-up area.
- Highs and lows: the Met Office publishes average daily maxima and minima on its 12 km grid; each is moved by the difference between the town’s 2 km mean temperature and the 12 km square’s, which carries the town’s own height and setting over.
- Weather station and sunshine: Met Office historic station data for Valley, 44 miles away, months of 1991–2020 averaged.
- Comparisons: every town and city of 2,500 or more across the UK, all four nations, read the same way.
Met Office HadUK-Grid · Met Office Climate Data Portal · Historic station data. Open Government Licence v3.0.
Questions about Dolgellau’s climate
How warm does Dolgellau get in summer?
July is the warmest month, with average highs of 19.7°C (67°F). About 8 days a year reach 25°C (77°F), fewer than 64% of UK towns.
How cold does Dolgellau get in winter?
February nights average 2.2°C (36°F). The air drops below freezing on about 40 nights a year, and about under 1 days a year stay below freezing all day.
How much rain does Dolgellau get?
About 1,755 mm (69 in) a year, more than almost every UK town. January is the wettest month (210 mm) and April the driest (96 mm).
How sunny is it?
The nearest Met Office station with a sunshine record, Valley (Anglesey) (44 miles away), averages 1,575 hours of bright sunshine a year. Sunshine isn’t on the town grid, so this is the station’s figure.
Where do these figures come from?
The Met Office’s HadUK-Grid 1991–2020 averages, which turn thousands of weather stations into a map of the UK in 2 km squares; the page reads the squares inside Dolgellau. They are 30-year averages, not a forecast.
Contains Met Office data © Crown copyright 2026, Open Government Licence v3.0. HadUK-Grid 1991–2020 averages via the Met Office Climate Data Portal; station averages from Met Office historic station data. Today’s forecast for Dolgellau →
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