Medical experts say there's been a four-fold rise in the number of Welsh cases of measles this year, compared to the previous 12 months.
From January to June there were 61 cases.
Public Health Wales says raising MMR vaccination rates is the key to tackling the problem.
Incidences of whooping cough were also up.
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Mainly dry with lengthy clear spells overnight and just a few showers likely, especially in the north and west.
Ysgol Uwchradd Caergybi became the UK's first comprehensive 65 years ago. Academies are now dominant in England, but certainly not in Wales.
Dry for most, but a few showers likely.