  Dielectric permittivity of supercooled volume water has been measured in the
range of temperatures from $-20\,^{\circ}$C to $-60\,^{\circ}$C at the
frequencies $7.6$~GHz and $9.7$~GHz. The measurements have been made using
microwave resonators and wetted silicate sorbents. From the data obtained, the
temperature dependences of the relaxation frequencies were updated for the
Debye model with two relaxation frequencies. The updated formulae for
dielectric permittivity of cold water may be applied to the frequency range
$7\ldots200$~GHz.
