Ice rarely forms: Seaham sees fewer frosts than 89% of UK towns
July afternoons average 19.5°C (67°F). The gap between a January night and a July afternoon is 18°C. Summers stay cool: July afternoons here are cooler than in 83% of UK towns. Long walks are most pleasant from June to September, when afternoons reach 17–20°C.
Met Office 1991–2020 averages for the town itself.
A year in Seaham at a glance
Each month’s typical high and low, in °C.
What a year in Seaham feels like
Typical highs and lows by season and by month, from the Met Office’s 1991–2020 averages.
About 650 mm of rain a year
November is the wettest month and March the driest. About 15 days a year bring 10 mm (0.4 in) or more. 43rd wettest of 52 County Durham towns of 2,500+.
Rain by month
Millimetres
26 air frosts and under 1 days of 25°C a year
On about 26 nights a year the air drops below freezing; days that stay below freezing are rare. About under 1 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 Durham
Durham is 10 miles south-west of Seaham, 102 m (335 ft) above sea level. It is the nearest of the 37 long-running stations the Met Office publishes in full.
| Month | High | Low | Rain | Air frosts |
|---|---|---|---|---|
| January | 6.9°C | 1.3°C | 53 mm | 10.3 |
| February | 7.8°C | 1.4°C | 46 mm | 9.8 |
| March | 9.9°C | 2.5°C | 41 mm | 6.5 |
| April | 12.5°C | 4.1°C | 51 mm | 3.2 |
| May | 15.4°C | 6.5°C | 45 mm | 0.8 |
| June | 18.0°C | 9.3°C | 61 mm | 0.0 |
| July | 20.2°C | 11.3°C | 61 mm | 0.0 |
| August | 19.9°C | 11.3°C | 67 mm | 0.0 |
| September | 17.4°C | 9.2°C | 57 mm | 0.0 |
| October | 13.5°C | 6.5°C | 63 mm | 1.2 |
| November | 9.7°C | 3.6°C | 76 mm | 4.6 |
| December | 7.1°C | 1.4°C | 61 mm | 10.4 |
| Year | 13.2°C | 5.7°C | 681 mm | 47 |
Met Office historic station data, Durham, 1991–2020 months averaged (a month needs 20 of the 30 years; estimated values counted, missing months left out). Sunshine: Campbell-Stokes recorder.
How Seaham 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 County Durham 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 |
|---|---|---|---|
| Seaham | 19.5°C | 2.0°C | 650 mm |
| Murton 1.9 mi | 19.5°C about the same | 1.5°C 0.6°C colder | 655 mm |
| South Hetton 3.4 mi | 19.3°C about the same | 1.2°C 0.9°C colder | 705 mm |
| Easington 3.6 mi | 19.5°C about the same | 1.8°C about the same | 646 mm |
| Easington Lane 3.8 mi | 19.3°C about the same | 1.2°C 0.9°C colder | 705 mm |
| Hetton-le-Hole 4.1 mi | 19.5°C about the same | 1.3°C 0.7°C colder | 735 mm |
| Haswell 4.5 mi | 19.3°C about the same | 1.1°C 1.0°C colder | 730 mm |
Seaham 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 | 7.3°C 45°F | 2.0°C 36°F | 4.7°C | 48 mm 1.9 in |
| February | 7.9°C 46°F | 2.0°C 36°F | 5.0°C | 42 mm 1.7 in |
| March | 9.8°C 50°F | 2.9°C 37°F | 6.3°C | 38 mm 1.5 in |
| April | 11.8°C 53°F | 4.3°C 40°F | 8.1°C | 48 mm 1.9 in |
| May | 14.6°C 58°F | 6.6°C 44°F | 10.6°C | 46 mm 1.8 in |
| June | 17.1°C 63°F | 9.3°C 49°F | 13.2°C | 62 mm 2.4 in |
| July | 19.5°C 67°F | 11.3°C 52°F | 15.4°C | 57 mm 2.2 in |
| August | 19.3°C 67°F | 11.5°C 53°F | 15.4°C | 67 mm 2.6 in |
| September | 17.2°C 63°F | 9.9°C 50°F | 13.6°C | 53 mm 2.1 in |
| October | 13.7°C 57°F | 7.4°C 45°F | 10.6°C | 62 mm 2.5 in |
| November | 10.2°C 50°F | 4.6°C 40°F | 7.5°C | 70 mm 2.8 in |
| December | 7.7°C 46°F | 2.2°C 36°F | 5.0°C | 57 mm 2.2 in |
| Year | 13.0°C | 6.2°C | 9.6°C | 650 mm |
Where Seaham’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 Seaham’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 Durham, 10 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 Seaham’s climate
How warm does Seaham get in summer?
July is the warmest month, with average highs of 19.5°C (67°F). About under 1 days a year reach 25°C (77°F), fewer than 98% of UK towns.
How cold does Seaham get in winter?
February nights average 2.0°C (36°F). The air drops below freezing on about 26 nights a year, and about under 1 days a year stay below freezing all day.
How much rain does Seaham get?
About 650 mm (26 in) a year, less than 80% of UK towns. November is the wettest month (70 mm) and March the driest (38 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 Seaham. 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 Seaham →
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