If you believe the main Swedish meteorological service SMHI then wedding guests and well-wishers would be well advised to bring their umbrellas to the cathedral.
SMHI has forecast that cloud and rain showers would pull in over the Swedish capital during the early morning. Rain showers are then expected to announce their presence at the regal festivities periodically throughout the afternoon ceremony.
The royal cortège could escape the rain however, if SMHI are to be believed, with clouds likely to break up a little as the procession winds its way through the city.
“But unfortunately there is also a risk of afternoon showers,” said duty meteorologist Alexandra Ohlsson to news agency TT.
The Sveriges Television (SVT) weather service also predicts the odd shower.
Weather Site klart.se and Norwegian yr.no are more optimistic and expect dry weather to hold for the whole of Saturday. The morning is set to be partly cloudy and becoming overcast around lunchtime but both sites rule out rain.
The Norwegians are the most optimistic even promising the odd glimpse of elusive late-June sunshine.
The forecasters are all however in agreement when it come to two areas -temperatures and winds, expecting 15-17 degrees and light winds in Stockholm during the royal wedding.