Could it be the phrase,
$\rm Rain \; up \; ahead?$
Because we have
$\rm Rain + up \, (looks \, up) + a \, head.$
the phrase has $11$ letters, as does the amount of raindrops in the picture;
the smile looks like a $\rm \cup$ which is the first letter of "up".
It's probably just a
Since the picture shows
A picture of falling water (rain) and a head
Hence, Rain + Head = Rainhead
Although I may be wrong
Could it be...
Tears of happiness? Teardrops + Happy face