Defining a column range limited to cells containing a value

Some months ago, Ron helped me with a formula to help with analysing the readings from my weather station.
An example cell entry looks like this...

=IF(COUNTIF($E$3:$E$4466,MAX($E$3:$E$4466))>=COLUMNS($E:E),
INDEX($B:$B,SMALL(INDEX(($E$3:$E$4466=MAX($E$3:$E$4466))*ROW($E$3:$E$4466),0),
COLUMNS($E:E)+COUNTIF($E$3:$E$4466,"<>"&MAX($E$3:$E$4466)))),"")

This works great, but every month the total number of readings varies because of the number of days (Feb has 28 etc) so I have to change the $E$4466 value in the above manually for every occurrence of the range.

Is there an alternative way of looking at the values in the range "from $E$3 to the last (bottom) cell in column E that is not empty". I could then substitute this in the formula above and it would be good-to-go for any month, no matter how many rows there were?

Thanks, Chris