18/12/2025 – Weather in Cornwall – Yellow Weather Warning For Rain

Published On: 18 December 2025Last Updated: 18 December 2025By CornishStuff

A yellow weather warning for rain has been issued by the Met Office, covering Thursday 18th December from 10:00am to 7:00pm.

The warning highlights the potential for travel disruption and possible flooding as a band of heavy rain moves across the area during the morning and afternoon before clearing eastwards in the evening.

What to Expect

Heavy rain may lead to spray and flooding on roads, which could make driving conditions difficult and result in some road closures. Where flooding occurs, there is a chance of delays or cancellations to bus and train services, and vehicles driven into floodwater could become stranded.

There is also a chance that homes and businesses could be flooded, causing damage to some buildings. Some communities may become cut off by flooded roads, and there is a small chance that fast flowing or deep floodwater could pose a danger to life.

The Met Office also warns of a slight chance of power cuts and the loss of other services to some homes and businesses.

Rainfall and Wind Details

Much of the warning area is expected to see between 15mm and 25mm of rain, although some locations could receive 40mm to 50mm. The highest rainfall totals are likely over high ground, including Dartmoor.

Strong winds are expected to accompany the rain and may worsen the impacts. Gusts of 60 to 70mph are possible along exposed parts of the south coast, with gusts of 40 to 50mph possible further inland across southwest England.

What You Can Do

People are advised to check whether their property could be at risk of flooding and to consider preparing a flood plan and an emergency flood kit if needed.

Those travelling should check road conditions or bus and train timetables in advance and be prepared to amend travel plans if necessary.

The Met Office also advises being prepared for possible power cuts by gathering essentials such as torches, batteries, a mobile phone power pack and other key items.

Weather warnings can change quickly, and people are encouraged to stay up to date with the latest local forecast throughout the day.

Why the Warning Is Yellow

The Met Office says the warning has a very low likelihood but a medium impact, meaning disruption is possible, particularly given the recent wet weather.

Residents are urged to remain aware of conditions as the day progresses.

South West England weather forecast

Headline:

Further spells of wet and windy weather to come.

Today:

The morning should start dry, but cloud will soon thicken with wet and potentially very windy weather sweeping across the region. The rain will become heavy, but it should turn more showery later. Winds remaining brisk. A mild day though. Maximum temperature 13 °C.

Tonight:

The evening will begin cloudy with blustery showers. Showers should become confined towards western coasts overnight with clear periods developing. Remaining breezy, although this should prevent a frost from forming. Minimum temperature 7 °C.

Friday:

Apart from a scattering of showers, mainly in the west, Friday promises to be a much drier and brighter day with sunny spells. Feeling cool due to the breeze though. Maximum temperature 11 °C.

Outlook for Saturday to Monday:

After a mostly fine start, wet and windy weather will move eastwards across the region on Saturday. Sunday and Monday look cloudy with further patchy rain. The wind easing though.

Updated: 04:00 (UTC) on Thu 18 Dec 2025