This data set contains three R objects: 'maxima.summer',
'minima.winter' and 'metadata'. 'maxima.summer' is a 100 by 424 matrix
giving the temperature in degrees, each column correspond to one
location. 'minima.winter is a 99 by 424 matrix giving the temperature
in degrees, each column correspond to one location. 'metadata' is a
424 by 5 data frame giving station identifier, the longitude,
latitude, elevation and the state for each station.