A warning has been issued for Norfolk and Suffolk with thunderstorms and heavy rain forecast. The yellow warning is in effect from 8.35pm on September 5 until 6am on September 6, according to the Met Office. The temperature is expected to be around 20C overnight across the county. There is a high chance that driving conditions will be affected by spray, standing water and hail which could lead to delays. Delays are also possible for train routes. The Met Office has also warned of a short-term loss of power and other services. Lightning can damage buildings and structures. And some flooding to businesses and homes is possible, which could lead to damage.