The speed of sound is given by:
[tex]v=331\sqrt[]{1+\frac{T}{273}}[/tex]then in this case the speed is:
[tex]v=331\sqrt[]{1+\frac{31}{273}}=349.29[/tex]The distance is given by:
[tex]d=vt[/tex]plugging the values given we have:
[tex]\begin{gathered} d=(349.29)(7) \\ d=2445.03 \end{gathered}[/tex]Therefore the storm is 2445.03 meters away