This is the outlook from the JMA the Japanese Met Agency. It is not a forecast but a general outlook. I have added the 3 images together, rotated them and added a red line showing the position of the UK. Orange colours is high pressure and Blue is low pressure.
Week 1, 29th March to 4th April.
High pressure is mainly in control, bringing above average temperatures. With a South westerly airflow this will bring some heavy showers at times.
Week 2, 5th April to 11th.
Low pressure to the North and high pressure ridge in the Atlantic.
Around average temperatures with rainfall around average.
Week 3-4 12th April to 25th.
This two week period is showing temperatures around average with rainfall around average for mid April.