The weather forecast for later this week is presenting a challenge for our meteorologists.

All the ingredients are present to produce significant rainfall on Thursday and Friday, but complex interactions in the atmosphere make it difficult to say with certainty where the rain will be most intense.

An area of low pressure is expected to develop and push north across the Bay of Biscay and western France on Wednesday night and into Thursday, arriving across southern England on Thursday morning. As it comes north, very warm air over the continent is expected to be drawn into the low pressure’s circulation, making it feel very humid across central and southern areas of the UK

Forecast pressure chart valid for 1am on Friday showing the location of the low pressure system over the southeast of the UK.

Warmer air can carry more moisture, and as such some very heavy rain is possible. However, this type of situation is difficult to forecast accurately a few days ahead and there is some uncertainty about which areas will see the heaviest rainfall. Current indications are that central and southern England and Wales are most likely to be affected. We may also have hail and thunder, this is most likely early on Thursday and then again Friday afternoon.

As we have already seen this summer, this type of weather situation has the potential to cause sudden, localised surface water flooding and hazardous travelling conditions.

Met Office National Severe Weather Warnings have been issued and these will be updated over the next few days as confidence in where and when we will see the heaviest rainfall increases.

Looking further ahead, the whole system is expected to clear away to the east during Saturday, with drier, fresher weather following to all parts with some sunshine.