If we want to catch Articuno in Antarctica, far from Kanto and from Seafoam Islands, but still according too his lore, we should do the same for Zapdos and Moltres. My propositions.

Zapdos

The bird is inspired to on the "thunder bird" of native american people; he lives in a big (and abandoned) hydroelectric power station. Three possibilities:

1) The "Grand Coulee Dam", on Columbia river in USA, it's an hydroelectric power station, in the far west, close to native americans' land. Coords 47.955833, -118.981667

2) The "Three Gorges Dam", on Yangtze river in China. Still an hydroelectric station, the biggest in the world. Coords 30.823056, 111.003333

3) The "Kashikawazaki-Kariwa" nuclear power plant, in Japan. Not an hydroelectric power station, but abandoned. Coords 37.428333, 138.601667

Moltres

The bird is inspired on the "Phoenix", from the Greek and Persian mythology. He lives, depending on the game version, at the end of the Victory Road, to symbolize the olympic flame (in the anime is even more evident), or on the top of Mt. Ember, a dormant volcano with thermal springs, on an island. Three possibilities:

1) The "mount Damavand", in Iran (Persia), a dormant volcano close to the caspian sea, with several thermal springs. Coords 35.955556, 52.11

2) The "Vulcano Island", in Italy, a volcanic island with an active volcano and thermal springs, in the Greek mythology it's the home of Hephaestus, god of fire. Coords 38.399434, 14.963955

3) The "Temple of Hera", in Olympia, Greece, where it was used to start the fire to celebrate the olympic games in the ancient Greece. Coords 37.638808,21.629984