This might not be as relevant as global warming changes the planet. Under normal conditions, though, this is how it is (or was, as the case may be):
* +15°C / 59°F
This is as warm as it gets in Norway, so we’ll start here.
People in Spain wear winter-coats and gloves.
The Norwegians are out in the sun, getting a tan.
* +10°C / 50°F
The French are trying in vain to start their central heating.
The Norwegians plant flowers in their gardens.
* +5°C / 41°F
Italian cars won’t start.
The Norwegians are cruising in cabriolets.
* 0°C / 32°F
Distilled water freezes.
The water in Oslo Fjord gets a little thicker.
* -5°C / 23°F
People in California almost freeze to death.
The Norwegians have their final barbeque before winter.
* -10°C / 14°F
The Brits start the heat in their houses.
The Norwegians start using long sleeves.
* -20°C / -4°F
The Aussies flee from Mallorca.
The Norwegians end their Midsummer celebrations.
Autumn is here.
* -30°C / -22°F
People in Greece die from the cold and disappear from the face of the earth.
The Norwegians start drying their laundry indoors.
* -40°C / -40°F
Paris start cracking in the cold.
The Norwegians stand in line at the hotdog stands.
* -50°C / -58°F
Polar bears start evacuating the North Pole.
The Norwegian army postpones their winter survival training awaiting real winter weather.
* -70°C / -94°F
The false Santa moves south.
The Norwegian army goes out on winter survival training.
* -183°C / -297.4°F
Microbes in food don’t survive.
The Norwegian cows complain that the farmers’ hands are cold.
* -273°C / -459.4°F
ALL atom-based movent halts.
The Norwegians start saying «Faen, it’s cold outside today.»
* -300°C / -508°F
Hell freezes over.
Norway wins the Eurovision Song Contest.
(Source: Unknown. Found on the internet)