I keep reading about "arctic conditions" being reported in the UK yesterday. A noticable drop in temperature can make for a noticable increase in the amount of priming required to start the engine, whether primed by an electric fuel pump, or a manual primer. It can also make for an increased chance of an engine fire due to over priming, so lots of things to be cautious about.
Cold conditions may require additional prime for a good start, but shouldn't result in low fuel flow.