How the rain moves inMet Office radar imagery shows the first organised line of showers arriving from the west late this evening, edging across Hertfordshire towards Harlow, Chigwell and the M25 corridor around 23:30. By around 02:00–02:45, a more continuous band of rain stretches from north-west Essex through Braintree and Chelmsford towards Basildon, with heavier bursts indicated in places along the line. This strip of rain continues to pivot north-east, taking wet weather into north Essex towards Sudbury and the Suffolk border in the early hours. Brighter colours embedded in the band point to heavier downpours, so some locations along this corridor could see a short burst of more intense rainfall. Western districts near the M25 – including Chigwell and Harlow – may see rain earliest, but conditions should also improve here first once the band clears eastwards.