Updated: 8 September 2026
One of the latest known spring frosts in London struck on 17 May 1935, when temperatures dropped to -0.6°C. This unusually late frost posed a real threat to blossoming plants already in full spring cycle.
Late spring frost date and temperature
The timing of the last frost in spring is vital for gardeners, farmers, and anyone who follows London’s seasonal rhythms. Using official Met Office data from the London St James’s Park station (1912–2025), we can see that the final frost of spring typically arrives much earlier than May, but sporadic late frosts do happen.
Looking at the historical record, the date of the last frost varies considerably from year to year. The earliest final frost in recent decades occurred on 20 January 2024, when temperatures fell to -0.3°C. At the other extreme, the latest recorded spring frost was on 17 May 1935, with -0.6°C. This wide range shows how spring frost risk can extend well beyond the expected season, creating challenges for early bloomers.
| Year | Last Frost Date | Minimum Temperature (°C) |
|---|---|---|
| 1917 | 16 April 1917 | -0.6 |
| 1928 | 18 April 1928 | -0.6 |
| 1935 | 17 May 1935 | -0.6 |
| 1997 | 21 April 1997 | -0.8 |
| 1924 | 10 April 1924 | -1.1 |
| 2023 | 11 March 2023 | -0.5 |
| 2024 | 20 January 2024 | -0.3 |
| 2025 | 2 February 2025 | -0.1 |
This table highlights selected years that recorded some of the latest spring frosts at London St James’s Park. The spread from early January to mid-May reflects how variable spring weather can be in the capital.
| Month | Average Frost Days |
|---|---|
| January | 6.2 |
| February | 5.4 |
| March | 2.5 |
| April | 0.4 |
| May | 0.0 |
| October | 0.2 |
| November | 2.1 |
| December | 4.7 |
On average, January sees the most frost days with 6.2 days below freezing, followed by February with 5.4. By April, frost days drop sharply to just 0.4 on average, while May typically records none. However, as the late frost dates show, exceptions can and do occur.
The coldest temperature ever officially recorded at London St James’s Park was -10.0°C on 15 February 1929. While this extreme is not directly related to spring frost risk, it helps illustrate London's potential for severe cold during winter and early spring.
| Year | Date of Last Frost | Minimum Temperature (°C) |
|---|---|---|
| 1935 | 17 May 1935 | -0.6 |
| 1936 | 23 April 1936 | -0.6 |
| 1997 | 21 April 1997 | -0.8 |
| 1928 | 18 April 1928 | -0.6 |
| 1917 | 16 April 1917 | -0.6 |
These five dates represent the most notable late frosts on record, all occurring well into mid-April or later. Such events can pose significant risks to blossoming plants and early outdoor crops.
Knowing when the last frost typically occurs in London is key for planning planting and protecting vulnerable species. The historical data from London St James’s Park clearly shows that while most frosts end by early April, late frosts have stretched into May—with the latest on record occurring in May 1935. Though rare, these events are a reminder to stay alert to chilly spring nights.
Source: Met Office, London St James’s Park station, data period 1912–2025
HistoClima Tools: discover the weather on the day you were born, your wedding day, or your birthday-week statistics.
AI-assisted content from official Met Office data, automatically verified. 🤖 IA-assisted content · Art. 50 EU AI Act
© 2026 HistoClima · data: Met Office (OGL v3.0) · not affiliated with Met Office · citation permitted with source.