Kate Middleton shows off her blondest hair ever during first joint appearance with Prince William in months

Summer looks good on Kate Middleton.

The princess, 43, debuted a new look as she stepped out for a joint official engagement with her husband, Prince William.

The Prince and Princess of Wales were all smiles Thursday during their visit to the Natural History Museum’s newly transformed gardens in London — marking their first joint public appearance in nearly two months.

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Though the garden was meant to be the centerpiece of the outing, it was Kate’s new blond hair that truly stole the spotlight.

The royal, who is a patron of the museum, let her caramel blond locks flow freely during the outing, for which she rocked a tweed blazer atop a crisp white shirt and a pair of dark suit pants.

She completed her business casual look with a pair of brown suede loafers and a necklace that features the initials of her three children, George, Charlotte and Louis. 

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Prince William wore a dark blazer atop a light blue shirt, and paired the look with a pair of dark colored suit pants.

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The sun-kissed couple were joined by school students from Manchester and London for their tour of the gardens, before the duo spoke to the youngsters about the importance of spending quality time out in nature.

As they arrived at the venue, the future king was seen lovingly placing his hand on his wife’s back as they entered the building.

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The princess was seen smiling and chatting to staff members when the great British weather showcased all its glory — prompting heavy rainfall to throw a spanner in the works during the visit.

Their visit marks the first time the mom of three was seen at an official royal engagement since she was joined by her family at the Wimbledon tennis championships in July.

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During her visit to the tennis tournament, the royal’s hair was noticeably darker.

The princess was greeted with a standing ovation when she walked toward her seat in the Royal Box on Centre Court to watch the women’s final.