The Carpe Diem Café series is set in Canada, so I decided to use CA spelling and other references. Some of these may be unfamiliar to you.
This means there are obvious differences from US spelling – like a plentitude of u’s. Weights and measures are also the peculiarly Canadian mix of metric and imperial. There are some figures of speech that might not be familiar to non-Canadians, as well.
This page offers a reference for all of that. I’m not a linguist, so it will be an incomplete reference.
Spelling
The thing you’ll notice most about Canadian spelling is our fondness for the letter u. Wiki says this is due to the French influence. (?)
• colour, savour, flavour, honour, splendour, etc.
• a fondness for z (which we call zed not zee) over s: realize, organize, etc.
• the er inversion – fibre instead of fiber, centre, meagre, etc.
• doubled consonants at the end of the verb before the suffix – travelled, travelling instead of traveled, traveling etc.
• also grey vs. gray and others
Weights & Measures
Officially, Canada uses the metric system. We used Imperial measures for a long time, so in reality, we mix the two up in a specific way.
Here’s a post from social media that sums it up perfectly:
Americans: I use miles and pounds
Europeans: I use kilometres and kilograms
Canadians: I’m 5’8, I weigh 150lbs, horses weigh 1000kgs, my house is an hour away and I drive 80 km/h to get there, I need a cup of flour and 1L of milk.
Distance:
A meter is a little longer than a yard. (39.25 inches)
A kilometer (often called a ‘klick’) is less than a mile.
A centimeter (1/100th of a meter) is almost half an inch.
Speed limits are posted in km/hour, distances between towns are measured by km, fabric is sold by the m, but more common references (the size of the killer zucchini in your garden, the length of a zipper, the width of a door, how much you tell the hairdresser to trim off your hair, your height) are often made in Imperial measurements.
Weight:
454 grams equals a pound.
A kilogram (1000 grams) is 2.2 pounds
Most Canadians buy food products by gram/kg, but know their own body weight in pounds. At farmers’ markets, vendors will often use pounds instead of kilos.
Volume:
A liter is roughly the same volume as a quart.
We buy gasoline by the liter, as well as milk and juice.
Figures of Speech
In addition, there are expressions that are regional. Often I’m unaware of their regionalism until I send out ARC’s and get questions from my team. I’ll keep a list of them here for your reference. Of course, it’s a work in progress.
In Just Trouble, Daphne is admiring Luke’s determination to pay support to Sylvia for Sierra and says:
“I think that Sylvia is going to have to go some to turn him down…”
‘To have to go some’ means to make an effort, usually against long odds. I’m going to have to go some to knit up my knitting wool stash in the next decade…
In Just Like Starting Over, Mike refers to the high number of tomatoes in the greenhouse.
“The magical alchemy of variables has come together and we have tomatoes for our tomatoes.“
‘tomatoes for our tomatoes’ is an expression of abundance. You can use it for anything. I, for example, have knitting wool for my knitting wool. 
Deborah Cooke: Author 