Tonbridge, a historic market town in west Kent, sits on the River Medway approximately 30 miles south-east of London. Its climate is classified as temperate oceanic (Köppen Cfb), typical of the south-east of England. This article provides a month-by-month overview of average temperature, rainfall, and daylight hours, drawing on long-term Met Office data for the nearest weather stations (e.g., Hadlow College, about 4 miles north-east). We also include practical advice for gardening, outdoor activities, and energy use.
Annual Climate Summary
Tonbridge enjoys relatively mild winters and warm summers compared to the UK average. The annual mean temperature is around 10.5°C (51°F). Average yearly rainfall is approximately 750 mm (29.5 inches), fairly evenly distributed but with slightly wetter autumn and winter months. Daylight hours range from under 8 hours in December to over 16 hours in June.
January
Average temperature: 4.5°C (40°F) — daily highs near 7°C (45°F), lows around 2°C (36°F).
Rainfall: 65 mm (2.6 inches) over 12 rainy days.
Daylight: 8 hours 20 minutes (sunrise ~7:55, sunset ~16:15).
Frost occurs on 8–10 nights. Snow is possible but usually light; Tonbridge lies in a low‑altitude area (about 30 m above sea level) so heavy snow is rare. The Tonbridge winter weather guide offers tips on driving and heating costs.
February
Average temperature: 4.8°C (40.6°F) — highs 8°C (46°F), lows 1.5°C (35°F).
Rainfall: 50 mm (2.0 inches) over 10 rainy days.
Daylight: 10 hours 0 minutes (sunrise ~7:15, sunset ~17:15).
February is often the driest winter month. Gardeners can start preparing soil for spring; local gardening advice suggests pruning roses in late February.
March
Average temperature: 7.2°C (45°F) — highs 11°C (52°F), lows 3.5°C (38°F).
Rainfall: 55 mm (2.2 inches) over 11 rainy days.
Daylight: 11 hours 50 minutes (clocks spring forward end of month).
Spring begins. The first daffodils appear in Haysden Country Park. Average sunshine increases to 120 hours for the month.
April
Average temperature: 9.5°C (49°F) — highs 14°C (57°F), lows 5°C (41°F).
Rainfall: 55 mm (2.2 inches) over 10 rainy days.
Daylight: 13 hours 50 minutes (sunrise ~6:00, sunset ~19:50).
April can bring showery weather. The Tonbridge Farmers' Market (second Saturday) sees seasonal produce. Daylight saving means longer evenings.
May
Average temperature: 13.0°C (55°F) — highs 17°C (63°F), lows 8.5°C (47°F).
Rainfall: 60 mm (2.4 inches) over 10 rainy days.
Daylight: 15 hours 30 minutes (sunrise ~5:10, sunset ~20:40).
Warm and increasingly sunny. The Tonbridge Castle grounds host events. Pollen counts rise; hay fever sufferers should monitor forecasts.
June
Average temperature: 16.0°C (61°F) — highs 20°C (68°F), lows 11.5°C (53°F).
Rainfall: 55 mm (2.2 inches) over 9 rainy days.
Daylight: 16 hours 30 minutes (sunrise ~4:45, sunset ~21:15) — longest day around 21 June.
Summer solstice brings maximum daylight. Average sunshine totals 210 hours. Ideal for outdoor swimming at Tonbridge Pool or walks along the Medway.
July
Average temperature: 18.0°C (64°F) — highs 22°C (72°F), lows 13.5°C (56°F).
Rainfall: 55 mm (2.2 inches) over 9 rainy days.
Daylight: 16 hours 0 minutes (sunrise ~5:00, sunset ~21:00).
Warmest month on average. Heatwaves can push temperatures above 30°C (86°F). The Tonbridge Carnival takes place in July. Summer activities guide lists events.
August
Average temperature: 17.5°C (63.5°F) — highs 22°C (72°F), lows 13°C (55°F).
Rainfall: 60 mm (2.4 inches) over 10 rainy days.
Daylight: 14 hours 30 minutes (sunrise ~5:45, sunset ~20:15).
Similar to July but slightly cooler. Thunderstorms are possible. The Tonbridge Town Centre hosts a summer fete. Summer forecast provides updates.
September
Average temperature: 15.0°C (59°F) — highs 19°C (66°F), lows 11°C (52°F).
Rainfall: 60 mm (2.4 inches) over 10 rainy days.
Daylight: 12 hours 40 minutes (sunrise ~6:30, sunset ~19:10).
Autumn begins. Mild and often settled. The Tonbridge Half Marathon usually occurs in September.
October
Average temperature: 11.5°C (53°F) — highs 15°C (59°F), lows 8°C (46°F).
Rainfall: 75 mm (3.0 inches) over 12 rainy days.
Daylight: 10 hours 40 minutes (clocks fall back end of month).
Wetter and cooler. Leaves change colour in the Weald. Heating demand rises. Energy saving tips help manage bills.
November
Average temperature: 7.5°C (45.5°F) — highs 10°C (50°F), lows 4.5°C (40°F).
Rainfall: 70 mm (2.8 inches) over 12 rainy days.
Daylight: 8 hours 50 minutes (sunrise ~7:20, sunset ~16:10).
Grey and damp. Fog is common in the valley. The Tonbridge Christmas lights switch‑on happens in late November.
December
Average temperature: 5.0°C (41°F) — highs 7°C (45°F), lows 2.5°C (36.5°F).
Rainfall: 65 mm (2.6 inches) over 12 rainy days.
Daylight: 7 hours 50 minutes (sunrise ~8:00, sunset ~15:50) — shortest day around 21 December.
Darkest month. Frost frequent. The Tonbridge Christmas market runs on the High Street.
Practical Considerations
Gardening
Tonbridge's USDA hardiness zone is 8b/9a, suitable for many perennials. Local garden centres like Haysden Garden Centre on Haysden Lane stock plants suited to the climate. Frost-sensitive plants need protection from November to March.
Home Heating
Average annual heating degree days (base 15.5°C) total around 2,000. Homes typically use gas central heating. Boiler servicing is recommended before winter.
Outdoor Activities
The Tonbridge to Penshurst walk is popular in dry months. Rain gear is essential October–March. Daylight hours affect cycling and running; head torches are useful in winter.