search for: thermoisoplethendiagramm

Hello, I would like to generate isolines of temperature for the 24 hours by the 12 month. Something like hier: http://www.diercke.de/bilder/omeda/800/12351E.jpg. On the x-axis are the month and on the y-axis the 24 hours, than as contour lines the temperature. My data are: 'data.frame': 288 obs. of 3 variables: $ Group.1: num 0 1 2 3 4 5 6 7 8 9 ... $ Group.2: num 1 1 1 1 1 1 1