One thing to remember here is that barometers measure air pressure. The clocks' forecasting is not at all affected by the temperature outside.
The only point we ask you to remember is that the clocks' internal mechanics are not likely to be very happy if hung very close above a hot radiator (or other powerful heat source) as the regular swings in temperature can affect the internal mechanism.
Whilst our instruction manuals request you don't hang your clock anywhere near a radiator, recent tests we've conducted show that the clocks are fine if you keep at least 50cm (20 inches) distance between the radiator and the clock frame.