  Assuming perfect collision efficiency, we demonstrate that turbulence can
initiate and sustain the rapid growth of very small water droplets in air even
when these droplets are too small to cluster, and even without having to take
gravity and small-scale intermittency into account. This is because the range
of local Stokes numbers of identical droplets in the turbulent flow field is
broad enough even when small-scale intermittency is neglected. This
demonstration is given for turbulence which is one order of magnitude less
intense than is typical in warm clouds but with a volume fraction which, even
though small, is nevertheless large enough for an estimated a priori frequency
of collisions to be ten times larger than in warm clouds. However, the time of
growth in these conditions turns out to be one order of magnitude smaller than
in warm clouds.
