Duchess Kate Middleton stuns in surprise appearance at London Stadium

Duchess Kate Middleton joined Prince William and Prince Harry for her second surprise appearance of the week on Wednesday.

Just a day after her due date was announced, the Duchess stepped out in the chilly fall weather to help celebrate 150 young sports coaches graduating from Coach Core, a mentoring program founded by the royals themselves. The event was held outside at London Stadium, home to West Ham's football club, where she met with some of the soccer players and was handed jerseys for Charlotte and George. 

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Kate sported a blue double-breasted blazer by designer Philosophy di Lorenzo, paired with a black turtleneck, black skinny jeans and heeled black booties. The blazer, which she also owns in red, reportedly retails for over $700.

The look is giving us major fall feels. 

Her unexpected outing comes just days after she made her baby bump debut in an elegant powder blue lace dress. Days later, she surprised at a royal event, dancing with Paddington the Bear at London's Paddington station. Suffering from hyperemesis gravidarum, or severe morning sickness, the Duchess was forced to pull out of a number of royal events over the past month. 

For more updates on her pregnancy, see the video above. 

See more of her impeccable royal style: