Her Majesty was due to attend a military celebration in Wales during the country's St David's Day celebrations, but was forced to cancel her planned engagements.
Buckingham Palace declined to comment on her condition, but a spokeswoman earlier confirmed the Queen would spend the weekend at Windsor.
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A chilly but dry and bright start with plenty of sunny spells today and feeling fresher for all.
Mist and fog in the west will be slow to clear for a dry and bright day but feeling fresher for all.
Rain clearing east tonight for a dry but fresher day tomorrow with plenty of sunny spells.