I found the following formula on mvps.org

AND($B1(TODAY()-WEEKDAY(TODAY())),$B1<=(TODAY()-WEEKDAY(TODAY())+7))

In additon to this I also need to check Cell C1 for data:

$C1=""""

I tried a few variations Excel didn't complain, but I didn't get the
expected results:

=AND($C1="""",
(AND($B1(TODAY()-WEEKDAY(TODAY())),$B1<=(TODAY()-WEEKDAY(TODAY())+7))))