In an average February, Rome has four days that dip below 32 degrees F; the average high is 56, and the average is 40. Paris averages 12 days each February below 32 degrees F; the average high is 45 and the average low is 34. Only you know what constitutes weather that is too cold to enjoy.
A fluorescent lamp or a fluorescent tube is a low pressure mercury-vapor gas-discharge lamp that uses fluorescence to produce visible light. An electric current in the gas excites mercury vapor which produces short-wave ultraviolet light that then causes a phosphor coating on the inside of the bulb to glow.
As humans cannot see UV light, there is one more step in the elaborate design of fluorescent bulbs. They key is in the phosphorous coating that lines the inner glass tube. When phosphor is exposed to UV light, it absorbs the energy and radiates it back out as visible light.