Heavy traffic is expected in Leeds later as people travelling to Leeds Festival take to the roads.
The event's not due to start until Friday, but holders of "early entry" passes will be arriving at the Bramham Park site today.
Drivers can get regular updates from West Yorkshire Police, which is stepping up their use of social media.
"The teams already make very good use of social media to keep communities informed about the work they are doing to address local issues but they will be stepping this up today and over the bank holiday weekend to bring people live updates on their work around these events.
“We hope it will give people attending these events a useful additional source of information that will help them to make the most of the weekend, whether they are residents or visitors from further afield.”
More top news
Rain overnight then cooler and breezy tomorrow but mainly dry and bright with sunny spells.
From Celts to Romans, Popes to pagans, the night of October 31 hasn't always been called Halloween, but it has been marked for centuries.
It was always going to be a very mild one, with a warm pocket of air travelling over the UK for Halloween - but it's now the warmest ever!