Homeowners across the UK are being warned of a potential ticking time bomb this autumn. They are being urged to act quickly to avoid a costly repair job this September.

The Met Office is predicting "showers or longer spells of rain" across the UK this month. Homeowners could be faced with costly repairs when the rain sets in if they have neglected blocked gutters and poor drainage. An expert is advising people to check their guttering and downpipes for leaves, debris and blockages as soon as possible. According to Bill Jarvis, Outdoor Surface and Driveway Protection Specialist at Premium Paints, water damage caused by poor drainage and blocked gutters costs homeowners around £1,550 on average. That figure can increase if foundations, driveways or exterior walls are impacted.

He explained: "Heading into autumn is the prime time to sort your drainage. If you don't clear gutters and manage runoff before the wetter months, water damage is almost guaranteed, especially after a summer of debris build-up most people haven't even noticed."

As well as checking for blockages, homeowners are also advised to check their patios and driveways for pooling water. They can improve drainage with proper slopes and runaway channels.

Bill also recommends sealing or resealing outdoor surfaces before the first frost of the season. This will help guard against water ingress - the unwated entry of water into a building.

Finally, homeowners should inspect fences and walls for damp spots. This may be an indication of drainage issues which need repairing as soon as possible.

He added: "Doing this maintenance now can save you thousands down the line, and increases your kerb appeal massively when your home needs it the most."

The warning comes ahead of what is expected to be a wet and showery September. Forecasters expect the month to be "unsettled" with low pressure dominating across the UK.

The Met Office long-range forecast, which runs from September 13-22, states: "Generally unsettled with low pressure dominating much of the period.

"This will mean showers or longer spells of rain will affect most of the UK at times. A deep low likely crosses the country later on the weekend clearing early next week bringing heavy rain and strong winds."

It adds: "Following this a return to showers with periods of longer spells of rain is likely. Thunderstorms and hail are also possible, as are some spells of strong winds, especially if further deeper lows affect the UK."

The forecast from September 23 until October 7 continues: "Areas of low pressure are likely at times, especially towards the north of the UK.

"These will bring spells of rain and showers, some of which are likely to be heavy at times with a risk of hail and thunder, and some windy conditions, especially if any deep lows form."