The July isotherm of 80° crosses the state a little N.
The January isotherm of 15° F.
Both the midwinter isotherm of Montreal and the midsummer one of Washington, D.C., pass through the state.
and S.; thus Odessa and Konigsberg are situated on the same winter isotherm of 28°; St Petersburg, Orel and the mouth of the Ural river on about 20°; and Mezen and Ufa on 9°.
The summer isotherm of 68° F., which in Europe passes through Cracow and Kaluga, traverses Omsk, Krasnoyarsk and Irkutsk, whence it turns north to Yakutsk, and then south again to Vladivostok.