Chapter 12


Goals: To investigate whether or not the climate record for selected locations indicates a "January thaw."


Daily maximum temperatures for the period January 5 to February 5 (which includes the time commonly referred to as the "January Thaw") for the locations listed below. Data is given for the period 1901-1990 (except for Tucson, where the data is for the period 1901-1986):

State College, PA
Albany, NY
Little Rock, AR
Minneapolis-St. Paul, MN
Charleston, SC
Fort Collins, CO
Kaufman, TX
Helena, MT
Tucson, AZ
Olga, WA

(a "-999" in the data indicates that the temperature is missing)


  1. For each station, compute the average daily maximum temperature for each calendar day from January 5 to February 5. For each station, plot these average daily maximum temperatures on a graph.

  2. Do you see a "January Thaw" at any of the stations? If so, how big of a temperature jump do you see and approximately when does it occur? Does it occur at the same time at all locations? Does the "January Thaw" appear to occur at stations in some parts of the country but not in others?

Other "Weather on the Web" Exercises

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