They serve as a natural fertilizer and help support the roots of future crops. They take in rain and allow it to flow into the soil instead of running off.
And finally the weather. After a cold start, most of the country should be warm and sunny. But towards late afternoon, rain will spread from Scotland to cover most parts by midnight.
And it had bad timing too because another storm that hit this part of the world days before Dennis arrived, so the ground was already soaked with rain likely making the flooding caused by Dennis even worse.