Photo: Llyfrgell Genedlaethol Cymru / The National Library of Wales from Wales/Cymru · Public domainRainfall in Penllergaer tops that of 94% of UK towns: 1,335 mm (53 in) a year
A clear January night here typically dips to 2.8°C (37°F). Only 18°C separates winter nights from summer afternoons. Winters are mild: January nights here are milder than in 91% of UK towns. Frost greets about 29 mornings a year, so leave time to clear the car.
Met Office 1991–2020 averages for the town itself.
A year in Penllergaer at a glance
Each month’s typical high and low, in °C.
What a year in Penllergaer feels like
Typical highs and lows by season and by month, from the Met Office’s 1991–2020 averages.
About 1,335 mm of rain a year
December is the wettest month and April the driest. About 46 days a year bring 10 mm (0.4 in) or more. 14th wettest of 19 West Glamorgan towns of 2,500+.
Rain by month
Millimetres
29 air frosts and 9 days of 25°C a year
On about 29 nights a year the air drops below freezing, and on about under 1 days it stays below freezing all day. About 9 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 Cardiff Bute Park
Cardiff Bute Park is 37 miles east of Penllergaer, 9 m (30 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 |
|---|---|---|---|---|
| January | 8.6°C | 2.5°C | 127 mm | 8.1 |
| February | 9.1°C | 2.5°C | 93 mm | 7.5 |
| March | 11.3°C | 3.9°C | 85 mm | 3.9 |
| April | 14.4°C | 5.7°C | 72 mm | 1.4 |
| May | 17.4°C | 8.5°C | 78 mm | 0.0 |
| June | 20.1°C | 11.3°C | 73 mm | 0.0 |
| July | 21.8°C | 13.1°C | 84 mm | 0.0 |
| August | 21.4°C | 12.9°C | 105 mm | 0.0 |
| September | 19.1°C | 10.7°C | 87 mm | 0.0 |
| October | 15.2°C | 8.0°C | 128 mm | 1.0 |
| November | 11.6°C | 4.9°C | 131 mm | 3.7 |
| December | 9.1°C | 2.9°C | 140 mm | 8.3 |
| Year | 14.9°C | 7.2°C | 1,201 mm | 34 |
Met Office historic station data, Cardiff Bute Park, 1991–2020 months averaged (a month needs 20 of the 30 years; estimated values counted, missing months left out). Sunshine: Campbell-Stokes recorder.
How Penllergaer 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 West Glamorgan 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 |
|---|---|---|---|
| Penllergaer | 21.0°C | 2.8°C | 1,335 mm |
| Grovesend 1.8 mi | 21.0°C about the same | 2.8°C about the same | 1,335 mm |
| Gorseinon 1.8 mi | 21.0°C about the same | 3.0°C about the same | 1,346 mm |
| Gowerton 2.4 mi | 21.0°C about the same | 3.0°C about the same | 1,345 mm |
| Loughor 2.8 mi | 21.0°C about the same | 3.0°C about the same | 1,267 mm |
| Pontarddulais 3.1 mi | 21.0°C about the same | 2.8°C about the same | 1,337 mm |
| Hendy and Fforest 3.6 mi | 21.0°C about the same | 2.8°C about the same | 1,337 mm |
Penllergaer 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 | 8.1°C 47°F | 2.8°C 37°F | 5.4°C | 150 mm 5.9 in |
| February | 8.7°C 48°F | 2.8°C 37°F | 5.8°C | 103 mm 4.0 in |
| March | 10.8°C 52°F | 4.0°C 39°F | 7.4°C | 92 mm 3.6 in |
| April | 13.8°C 57°F | 5.7°C 42°F | 9.7°C | 76 mm 3.0 in |
| May | 16.8°C 62°F | 8.3°C 47°F | 12.6°C | 78 mm 3.1 in |
| June | 19.4°C 67°F | 11.2°C 52°F | 15.3°C | 82 mm 3.2 in |
| July | 21.0°C 70°F | 13.0°C 55°F | 17.0°C | 94 mm 3.7 in |
| August | 20.7°C 69°F | 12.9°C 55°F | 16.8°C | 105 mm 4.1 in |
| September | 18.5°C 65°F | 10.9°C 52°F | 14.7°C | 102 mm 4.0 in |
| October | 14.9°C 59°F | 8.3°C 47°F | 11.6°C | 151 mm 6.0 in |
| November | 11.2°C 52°F | 5.4°C 42°F | 8.3°C | 152 mm 6.0 in |
| December | 8.9°C 48°F | 3.3°C 38°F | 6.1°C | 152 mm 6.0 in |
| Year | 14.4°C | 7.4°C | 10.9°C | 1,335 mm |
Where Penllergaer’s numbers come from
Averages over 30 years, not a forecast.
- Mean temperature, rain and day counts: HadUK-Grid 1991–2020 averages for the Met Office 2 km grid square nearest Penllergaer’s centre (the town is smaller than one square).
- 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 Cardiff Bute Park, 37 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 Penllergaer’s climate
How warm does Penllergaer get in summer?
July is the warmest month, with average highs of 21.0°C (70°F). About 9 days a year reach 25°C (77°F), fewer than 58% of UK towns.
How cold does Penllergaer get in winter?
January nights average 2.8°C (37°F). The air drops below freezing on about 29 nights a year, and about under 1 days a year stay below freezing all day.
How much rain does Penllergaer get?
About 1,335 mm (53 in) a year, more than 94% of UK towns. December is the wettest month (152 mm) and April the driest (76 mm).
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 Penllergaer. 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 Penllergaer →
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