This is the problem with a lot of those who look at the daily weather as a snapshot as to what is happening with the climate. Yes, there can still be cold spells when global climate change and global warming is occurring. Global warming takes into account changes as a whole over a large swatch of time and over various regions, not just a week at an individual property. That's why you need to look at the bigger picture: As a whole the planet is warming at unprecedented rates since industrialization. Yes, some places may actually get colder but as a whole the planet is getting warmer. Individual effects will vary but the consequences of such warming are drastic, with more severe storms and chaotic events.