Llandeilo sits near the top of UK towns for rain, with 1,429 mm (56 in) a year
Midsummer highs settle at about 20.4°C (69°F). Seasons differ by 18°C, from the coldest nights to the warmest afternoons. Winters are mild: January nights here are milder than in 90% of UK towns. Windscreens need scraping on about 38 mornings a year, the nights the air drops below 0°C.
Met Office 1991–2020 averages for the town itself.
A year in Llandeilo at a glance
Each month’s typical high and low, in °C.
What a year in Llandeilo feels like
Typical highs and lows by season and by month, from the Met Office’s 1991–2020 averages.
About 1,429 mm of rain a year
December is the wettest month and April the driest. About 50 days a year bring 10 mm (0.4 in) or more.
Rain by month
Millimetres
Sunshine by month
Hours of bright sunshine at Aberporth
38 air frosts and 8 days of 25°C a year
On about 38 nights a year the air drops below freezing, and on about under 1 days it stays below freezing all day. 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 Aberporth
Aberporth is 30 miles north-west of Llandeilo, 133 m (436 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 | 7.8°C | 3.4°C | 90 mm | 4.5 | 60 |
| February | 7.9°C | 3.3°C | 67 mm | 3.8 | 79 |
| March | 9.4°C | 4.2°C | 58 mm | 1.8 | 127 |
| April | 11.6°C | 5.7°C | 54 mm | 0.4 | 172 |
| May | 14.3°C | 8.2°C | 55 mm | 0.0 | 210 |
| June | 16.6°C | 10.7°C | 64 mm | 0.0 | 203 |
| July | 18.3°C | 12.5°C | 67 mm | 0.0 | 187 |
| August | 18.3°C | 12.7°C | 75 mm | 0.0 | 169 |
| September | 16.7°C | 11.2°C | 71 mm | 0.0 | 141 |
| October | 13.6°C | 8.9°C | 107 mm | 0.0 | 99 |
| November | 10.5°C | 6.2°C | 117 mm | 0.6 | 59 |
| December | 8.5°C | 4.1°C | 107 mm | 3.5 | 49 |
| Year | 12.8°C | 7.6°C | 931 mm | 15 | 1,554 |
Met Office historic station data, Aberporth, 1991–2020 months averaged (a month needs 20 of the 30 years; estimated values counted, missing months left out). Sunshine: Kipp & Zonen recorder.
How Llandeilo 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 Dyfed 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 |
|---|---|---|---|
| Llandeilo | 20.4°C | 2.7°C | 1,429 mm |
| Llandybie 4.6 mi | 20.3°C about the same | 2.4°C about the same | 1,551 mm |
| Penybanc 6.4 mi | 20.2°C about the same | 2.6°C about the same | 1,596 mm |
| Ammanford 6.4 mi | 20.6°C about the same | 2.8°C about the same | 1,522 mm |
| Glanaman 6.5 mi | 19.9°C 0.5°C cooler | 2.3°C about the same | 1,713 mm |
| Cross Hands and Pen-y-groes 6.9 mi | 19.5°C 0.9°C cooler | 2.1°C 0.6°C colder | 1,678 mm |
| Capel Hendre 7.3 mi | 20.2°C about the same | 2.3°C about the same | 1,604 mm |
Llandeilo 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 | 8.2°C 47°F | 2.7°C 37°F | 5.4°C | 163 mm 6.4 in |
| February | 8.5°C 47°F | 2.4°C 36°F | 5.4°C | 114 mm 4.5 in |
| March | 10.8°C 51°F | 3.6°C 39°F | 7.2°C | 98 mm 3.8 in |
| April | 13.4°C 56°F | 5.1°C 41°F | 9.3°C | 80 mm 3.2 in |
| May | 16.7°C 62°F | 7.7°C 46°F | 12.1°C | 85 mm 3.3 in |
| June | 18.9°C 66°F | 10.4°C 51°F | 14.8°C | 84 mm 3.3 in |
| July | 20.4°C 69°F | 12.3°C 54°F | 16.4°C | 96 mm 3.8 in |
| August | 20.0°C 68°F | 12.1°C 54°F | 16.2°C | 110 mm 4.3 in |
| September | 18.0°C 64°F | 9.9°C 50°F | 14.0°C | 109 mm 4.3 in |
| October | 14.5°C 58°F | 7.7°C 46°F | 11.1°C | 158 mm 6.2 in |
| November | 10.9°C 52°F | 4.7°C 40°F | 7.8°C | 162 mm 6.4 in |
| December | 8.4°C 47°F | 2.8°C 37°F | 5.6°C | 170 mm 6.7 in |
| Year | 14.1°C | 6.8°C | 10.4°C | 1,429 mm |
Where Llandeilo’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 Llandeilo’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 Aberporth, 30 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 Llandeilo’s climate
How warm does Llandeilo get in summer?
July is the warmest month, with average highs of 20.4°C (69°F). About 8 days a year reach 25°C (77°F), fewer than 61% of UK towns.
How cold does Llandeilo get in winter?
February nights average 2.4°C (36°F). The air drops below freezing on about 38 nights a year, and about under 1 days a year stay below freezing all day.
How much rain does Llandeilo get?
About 1,429 mm (56 in) a year, more than 95% of UK towns. December is the wettest month (170 mm) and April the driest (80 mm).
How sunny is it?
The nearest Met Office station with a sunshine record, Aberporth (30 miles away), averages 1,554 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 Llandeilo. 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 Llandeilo →
Contains public sector information licensed under the Open Government Licence v3.0. Contains HM Land Registry data © Crown copyright and database right 2026. Contains OS data © Crown copyright and database right 2026 (ONS boundaries). Northern Ireland: Source: NISRA; contains Land & Property Services data and Ordnance Survey of Northern Ireland information, © Crown copyright, licensed under the Open Government Licence v3.0. Scotland: contains National Records of Scotland data, Registers of Scotland data and SEPA data, © Crown copyright / © SEPA 2025, licensed under the Open Government Licence v3.0.