Peter Stokes, from the Office for National Statistics, says changing numbers of Welsh speakers in different parts of the country can partly be explained by migration within Wales.
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All primary and secondary schools in Wales have been categorised in a new colour-coded system. Is your school green or red?
A yellow warning for snow and ice on Thursday night and Friday has been issued.
Some wintry showers and staying windy with a significant wind chill and widespread frost developing