Country guide
United Kingdom weather by month
July and August are the best starting point for a United Kingdom beach holiday, while late spring and early autumn suit city trips with less emphasis on warmth. Summer daytime averages reach 20°C, but even the warmest sea average is only 17°C, so swimming can feel cool. September is a useful compromise for outdoor plans, with the fewest rain days at 10. Whatever the month, pack for rain rather than expecting a reliably dry spell.
- Hottest month
- 20.4°CJuly
- Coolest month
- 8.3°CJanuary
- Warmest sea
- 16.6°CAugust
- Destinations tracked
- 2warmest: London
United Kingdom, month by month
A little perspective
United Kingdom through the year
Country figures are the mean of the 2 destinations listed below; individual resorts can differ by several degrees.
| Month | Day | Night | Sea | Sun/day | Rain mm | Rainy days | Days 25°C+ |
|---|---|---|---|---|---|---|---|
| January | 8.3°C | 3.7°C | 9.8°C | 2.2 | 72 | 14 | 0% |
| February | 8.5°C | 3.4°C | 9.1°C | 2.8 | 61 | 12 | 0% |
| March | 10.5°C | 4.4°C | 9.1°C | 3.5 | 55 | 12 | 0% |
| April | 12.9°C | 5.9°C | 10.0°C | 4.8 | 57 | 12 | 0% |
| May | 15.8°C | 8.8°C | 11.8°C | 5.2 | 58 | 11 | 1% |
| Junebest | 18.5°C | 11.6°C | 14.0°C | 5.5 | 60 | 11 | 4% |
| Julybest | 20.4°C | 13.7°C | 16.0°C | 5.6 | 61 | 12 | 10% |
| Augustbest | 20.2°C | 13.8°C | 16.6°C | 4.9 | 67 | 12 | 7% |
| September | 18.1°C | 11.9°C | 16.0°C | 4.2 | 56 | 10 | 1% |
| October | 14.6°C | 9.4°C | 14.8°C | 3.2 | 77 | 13 | 0% |
| November | 11.0°C | 6.4°C | 12.8°C | 2.3 | 81 | 14 | 0% |
| December | 8.7°C | 4.4°C | 11.0°C | 2.2 | 79 | 13 | 0% |
Day = average daytime high, night = average night-time low, 1991-2020.Sun is hours per day; rainy days count 1 mm or more.
Day, night and sea
Monthly average temperatures, 1991-2020
- Day
- Night
- Sea
When to go to United Kingdom
No month averages 25°C by day - United Kingdom is a warm-season rather than a hot destination. Even in summer the sea stays below 22°C (16°C in July). Winter (December to February) averages 9°C by day - cool, closer to a British spring. November is the wettest month (81 mm) and March the driest (55 mm).
Destinations in United Kingdom
Each has a 12-month table; our most searched places have month-by-month detail pages.
Warmest place in United Kingdom each month
| Month | Warmest destination | Day | Coolest destination | Day | Warmest sea |
|---|---|---|---|---|---|
| January | Cornwall | 9°C | London | 7°C | Cornwall 10°C |
| February | Cornwall | 9°C | London | 8°C | Cornwall 9°C |
| March | London | 11°C | Cornwall | 10°C | Cornwall 9°C |
| April | London | 14°C | Cornwall | 12°C | Cornwall 10°C |
| May | London | 17°C | Cornwall | 15°C | Cornwall 12°C |
| June | London | 20°C | Cornwall | 17°C | Cornwall 14°C |
| July | London | 22°C | Cornwall | 19°C | Cornwall 16°C |
| August | London | 21°C | Cornwall | 19°C | Cornwall 17°C |
| September | London | 19°C | Cornwall | 18°C | Cornwall 16°C |
| October | London | 15°C | Cornwall | 15°C | Cornwall 15°C |
| November | Cornwall | 12°C | London | 10°C | Cornwall 13°C |
| December | Cornwall | 10°C | London | 8°C | Cornwall 11°C |
The shape of the year
Winter suits travellers happy to build their days around indoor stops: January and February average 8°C by day, with nights colder still. Spring brings a gradual improvement rather than an early switch to summer. March remains cool, while April and May become more comfortable for walking, though a jacket stays useful. June offers milder evenings before July and August bring the highest daytime averages. September keeps some summer warmth, making it a practical alternative for an outdoor-heavy trip. October is cooler and has more rain days, while November and December call for warmer layers again. Rain remains part of the picture throughout, so keep outdoor plans flexible.
London, Cornwall and choosing a city break
London is slightly warmer overall than Cornwall, with average daytime temperatures across the year of 14.2°C and 13.7°C respectively. That is a small gap, not a reason to pack for a different climate. It also does not establish how every part of the United Kingdom compares, so avoid treating either place as a promise of conditions elsewhere. For a city break, May and September offer a useful balance: daytime averages of 16°C and 18°C make walking more appealing than in winter without needing peak summer warmth. Bring an extra layer for evenings. London’s warmer annual average is a modest advantage, but rain protection still belongs in your bag.
When to go for the beach
For a beach-focused trip, favour July or August for the warmest daytime conditions, but keep expectations realistic: an average of 20°C is comfortable rather than hot. August has the warmest sea at 17°C, so it is the better starting point if swimming matters most, though the water can still feel chilly. September remains an option, with the sea at 16°C and daytime temperatures averaging 18°C. June is milder on land than in the water, with a sea average of 14°C. Earlier in spring, think coastal walks rather than comfortable swimming. Take a layer for sitting outside and have an alternative plan for wet weather.
A little more detail
United Kingdom weather FAQs
Plain answers, grounded in the averages.
When is the best time to visit United Kingdom?
Weighing warmth, low rainfall and sunshine across 2 destinations, the best months for United Kingdom are July, August, June. July is the hottest month (average high 20.4°C) and January the coolest (8.3°C).
How many months is United Kingdom over 25°C?
No month averages 25°C across our United Kingdom destinations; the warmest is July at 20.4°C.
Which is the hottest place in United Kingdom?
Over the year, London has the highest average daytime temperature of the 2 United Kingdom destinations we track (14.2°C averaged across all months).
Which month has the fewest rain days?
September has the fewest rain days at 10, alongside a daytime average of 18°C. That makes it a sensible choice for walking and mixed outdoor plans, but it is not a guarantee of dry weather. Keep waterproof clothing handy.
What should I pack for a winter trip?
Pack warm layers, a waterproof outer layer and shoes you are comfortable wearing in rain. January and February average 8°C by day, while February nights average 3°C. Plan for colder evenings rather than relying on daytime temperatures when choosing clothes.
About these averages
ERA5-Land climate reanalysis via Open-Meteo (11 km grid), 1991-2020
Averages computed from daily values at 2 destination points.Records are the highest and lowest daily values in that 30-year period, not all-time records. These are climate averages, not a forecast for your trip. How we measure holiday weather
- Hot · 25°C+
- Warm · 20°C to below 25°C
- Mild · 15°C to below 20°C
- Cool · below 15°C