Or to put it another way, you'll not believe your eyes when it starts raining Yorkshire sayings in Sheffield.
Off The Shelf book festival organisers what your help to suggest the best local words and expressions to use in this magical UK first.
American street artist Peregrine Church will bring his amazing water-activated art to the city after wowing Seattle with words and images that can only be seen when it rains.
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There will be a map to show where the invisible words are, encouraging people to visit them all like a cross between the herd of elephants and Pokemon Go.
Peregrine, who is getting a global name for himself, uses a special, harmless and transparent solution that repels water, so his stenciled art - called Rainworks - can only be seen when the ground is wet.
Water rolls off the treated area to reveal a light contrast to the dark soaked ground around it..
"The stuff that makes Rainworks is biodegradable, environmentally friendly and completely non- toxic. It's a spray on substance I use with a stencil," he said.
"I make the world a more interesting place.
"The messages and images are designed to make a rainy day a little bit better."
Off The Shelf will reveal his Rainworks art, including song lyrics by the likes of Pulp, Richard Hawley and Reverend and the Makers, when he also appears as a guest speaker at the end of the festival, on Saturday, October 29.
It will include an extra special Rainworks text, written for the festival by playwright and writer Alan Bennett. It's about libraries and will appear in front of the central library.
The Rainworks will continue to appear when it rains for months to come.
And Off The Shelf bosses want you to tell them what some of the words and sayings should be used - including those you might only hear in Yorkshire.
Maria de Souza, arts officer and co-organiser of Off the Shelf, said: "Sites in the city and some out of town will reveal these Yorkshire sayings and Sheffield song lyrics, but only when it rains.
"We now want folk to suggest which of their favourite local expressions we should use and bring to life on the streets of Sheffield - but only when it rains.
"Weather and rain sayings would be wonderful. We have to make templates for the words we choose so we want local people to let us know as soon as possible.
"In our office we have had suggested mardy bum, aye up, put wood int’ hole, you don’t get owt for nowt and sling thi hook.
"I’ve become familiar with these great Sheffield sayings after years of living in Sheffield - having migrated from the South!”
* Rainworks artist Peregrine Church will talk at the 25th annual festival about the project and his work as an artist in the Winter Garden on Saturday, October 29, at 6pm Tickets are free but must be booked on 0114 273 4400 or by emailing [email protected]The project is part of Year of Making and in collaboration with Yellow Bus Events and Festival of the Mind. Funding support comes from Arts Council England, University of Sheffield and Sheffield BID.
This year's 25th annual festival runs from October 8 to 29, with around 200 events at venues across the city and some major talks outside those dates. The guest speaker line-up includes celebrity chef Hugh Fernley Whittingstall, TV presenter and actor Tony Robinson, award winning journalist John Pilger, Labour's former home Secretary Alan Johnson, New Faces winner, singer and actress Patti Boulaye, artist, illustrator and hip-hop musician Kid Acne and best selling authors such as Nick Hornby,
There will be special events to mark the 400th anniversary of the death of William Shakespeare, 200 years since the birth of Charlotte Brontë and 100 years since the birth of Roald Dahl. Former deputy prime minister and Sheffield's Hallam MP Nick Clegg kicked the festival off with a talk about his new book, Between The Extremes.
For more information visit offtheshelf.org.uk/READ MORE: 23 phrases you need to learn if yoiu are new to SheffieldREAD MORE: VIDEO PREVIEW: Nick Clegg among big names at Sheffield's Off The Shelf 2016 book festivalREAD MORE: 11 PHRASES YOU’LL HEAR IN SHEFFIELD