weather in jersey st helier
St Helier: Weather Forecast. The warmest day over the next 7 days in St Helier is forecast to be 23rd August at 26Â°C (79Â°F) and the warmest night on 23rd August at 19Â°C (67Â°F). The average temperature over the next 7 days is forecast to be 21Â°C (70Â°F) and there will be 2 days of sunshine . The average for August is 17Â°C (62Â°F) in St Helier.