During the month of January 2013, Denver, CO recorded a 78°F difference between maximum and minimum temperatures. Does that tell you anything about whether it was warmer or colder than normal? No, it does not. For the entire month, Denver was 0.4°F below normal (30.3°F vs. 30.7°F). But the maximum temperature of 66°F was recorded on the 24th while the minimum temperature of -12°F was recorded on the 12th.
Figure 1. Time series of temperature at Denver, CO during January 2013. Daily high temperatures are in red, daily low temperatures are in blue, daily average temperatures are in green, climatological normal (1981-2010) high temperatures are in light gray, and normal low temperatures are in dark gray. [Source: NWS]
Precipitation was below normal again during January 2013. 0.31″ of liquid water equivalent precipitation fell during the month, compared to 0.41″ normally. For the first time in my life, rain fell across the Denver metro area in January! Two days after hitting the high for the month, the National Weather Service recorded 0.01″ of rain on the 26th. I haven’t read anything regarding historical rain in Denver in January, but I think such an event is very rare indeed. 4.6″ of snow fell, which was 2.4″ below the normal of 7.0″.