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| NHTP | Centre(s) of circulation | Natural signature over Finland in positive phase | Reference |
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| North Atlantic Oscillation (NAO) | Ponta Delagada (Azores) and Stykkisholmur (Iceland) | Strong westerly circulation bringing warmer and wetter weather than normal | Barnston and Livezey [38], Irannezhad et al. [35, 39] |
| Arctic Oscillation (AO) | A dipole between the polar cap area and the adjacent zonal ring centred along 45°N | Low pressure in the Arctic and high pressure at midlatitudes, leading to warmer and wetter weather than normal | Thompson and Wallace [40], CPC [11], Irannezhad et al. [35, 39] |
| East Atlantic (EA) | North-south dipoles across the North Atlantic | Intensive westerly circulation, causing the weather to be warmer and wetter than normal | Barnston and Livezey [38], CPC [41], Irannezhad et al. [35, 39] |
| West Pacific (WP) | Kamchatka (Russia) and a centre between the western, North Pacific, and South Asia and East Asia | North-south dipole anomalies causing the weather to be wetter than normal in February and colder than normal in spring and summer | Irannezhad et al. [35, 39] |
| East Atlantic/West Russia (EA/WR) | Western Europe, northwest Europe, and Portugal in spring and autumn; Caspian Sea in winter and Russia | Northerly and northwesterly circulation across the Baltic Sea, resulting in milder and drier weather than normal | Barnston and Livezey [38], Lim and Kim [42], Irannezhad et al. [35, 39] |
| Scandinavia (SCA) | West of Europe, Mongolia, and Scandinavia | High pressure over Scandinavia, bringing milder and drier weather than normal | Barnston and Livezey [38], Bueh and Nakamura [43], Irannezhad et al. [35, 39] |
| Polar/Eurasia (POL) | North Pole, Europe, and northeastern China, | Strong polar vortex resulting in milder and drier weather than normal | CPC [41], Irannezhad et al. [35, 39] |
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