  Low frequency acoustic wave generation is studied taking into account the
effect of stratification, inhomogeneity of background velocity profile and
temperature fluctuations. It is shown that for the typical parameters of
convective storms the dipole radiation related to temperature inhomogeneities
is at least of the same order as radiation of Lighthill's quadrupole source. It
is also shown that the source related to stratification could have valuable
contribution whereas some other sources are shown to be inefficient.
