It always puts a damper on one's evening when the weather ruins a carefully put-together look.
And Kate Middleton must put a great deal of effort onto perfecting her red carpet glamour.
Luckily, gallant Prince William made sure that not a drop of water touched his bride as he shielded her from the rain at the Leicester Square premiere of Steven Spielberg's War Horse this evening.
The 29-year-old showed off her sylph-life figure in a stunning floor-length gown.
Her three-quarter-length sleeves exhibited her slender wrists, with the Duchess opting for minimal jewellery in favour of maintaining the focus on her dress.
Kate has exhibited a fondness for lace before, and the delicate outer layer of her skirt certainly made for a beautiful finish.
She wore her engagement ring and a delicate silver bracelet for an understated decorative touch, and carried a simple black velvet clutch.
Kate celebrates her 30th birthday tomorrow, but is not expected to have a lavish party to mark the occasion.