Prince Harry and Meghan Markle
It might rain on Prince Harry and Meghan Markle's royal wedding. Pictured: Prince Harry and Markle attend a reception for Women's Empowerment at the Royal Aeronautical Society in central London, on the fourth day of the Commonwealth Heads of Government Meeting (CHOGM) on April 19, 2018. Getty Images/Chris Jackson

It might rain on Prince Harry and Meghan Markle's big day.

According to Accuweather, the blazing summer scorch will likely subside by next week. Shower, gusts and lightning will possibly meet the guests of Prince Harry and Markle's royal wedding.

"It is a bit far off to give a definite picture," said a Met Office spokesman, confirming that the weather will not be great when Prince Harry and Markle tie the knot. "But the trend for that period is mixed, so there are likely to be dry and sunny spells but also spells of rain."

"Outbreaks of rain will develop in the northwest, and spread erratically eastwards through Friday into Saturday, with brighter and showery weather following from the west," the Met Office website read. "Thereafter a rather changeable weather pattern looks likely, at least at first, with showers or longer spells of rain mainly in the west, but with a chance of some persistent rain in southern areas at times and with a low risk of thunderstorms here too."

On Tuesday, Kensington Palace announced that Prince Harry and Markle selected an Ascot Landau carriage for their wedding procession through the Windsor streets. It has an open design so the couple can easily be seen by well-wishers.

However, the weather forecast might force Prince Harry and Markle to change their plans. The actress is reportedly obsessed with the atmospheric condition on her wedding day.

"Like all brides, Meghan is all over the arrangements and a bit stressed," a source told The Sun. "But the one thing she can't control is the weather. She is asking about it several times a day."

Prince Harry and Markle are tying the knot on May 19 at St. George's Chapel at Windsor Castle. According to reports, the couple has planned every detail and even released seven pages of critical guidance with a list of do's and don't's for the royal wedding.

"All guests will be asked to surrender mobile telephones… and any devices used for image capture," the guidance read. "It should be noted that gifts cannot be brought to St George's Chapel or the Reception that follows at Windsor Castle. Guests are advised to seek further guidance on delivery arrangements for any gifts to Kensington Palace."

The guests' dress code is the standard morning coat or lounge suit for men and dress and hat for women. The use of toilets is scheduled. Guests cannot use it during the ceremony.