Short answer
Choose cloth for the places and seasons where you expect to wear these overcoats. Ask the tailor about fibre, weight, weave and care for the specific options; a city's name alone does not determine the right cloth.
Double-faced cashmere for the serious north, heavy flannel and wool–cashmere blends for the mid-winter cities, with storm details discussed in the room.
November to March plans lighter wools and open weaves that travel between climates.
The full cloth books span fresh open weaves through four-season high-twist to winter flannels and cashmere blends. Bring the tailor your calendar; the shortlist comes back two or three cloths wide.
The itinerary is a proposal: months are planned, dates and venues confirmed individually. Final quotations are confirmed in writing before you commit.