sentences:  Winter conditions are highly dependent on the source region of the air mass that dominates during a particular month, resulting in tremendous variability from one year to the next.For example, in January 2006, the city experienced typically continental winter weather, resulting in an average daytime high of , recording a nighttime low of  on the 24th.The very next year, in January 2007, the weather was predominantly of the Atlantic type, resulting in an average high of and occasional days above , more typical of coastal locations in Western Europe.