Summing range of numbers according to variable dates

I'm having a hard time finding the right formula for a 2-row table. I have a row of dates which starts with today(), adds 1, and ends sometime in the future:

=IF(B2="","",IF(B2+1<$U$3,B2+1,""))

Row 2 is a number corresponding with each date.

What I'm trying to do, without using macros, is sum the numbers in Row 2 for each month. A simple summation will not work because the dates change overtime.

How would I go about summing each 30 or so numbers for each month?

Thank you in advance for taking your time to help me out.

Nate

Edit: Instead of finding a solution to this problem, I changed the problem so that it no longer required this particular solution. Thanks again.