High temperatures forecast for this week thanks to Spanish Plume - before familiar showers could return . Sunny spells for South East and south Wales as temperatures could hit 21C in South West later this week . 9C higher than normal for month - and a few degrees warmer than current temperatures in Mallorca , Spain . Mercury set to rise steadily until Friday - and Rome is expected to hit 16C , Athens 16C and Marseille 18C .
High temperatures forecast for this week thanks to Spanish Plume - before familiar showers could return . Sunny spells for South West and south Wales as temperatures could hit 21C in South East later this week . 9C higher than normal for month - and a few degrees warmer than current temperatures in Mallorca , Spain . Mercury set to rise steadily until Friday - and Rome is expected to hit 16C , Athens 16C and Marseille 18C .