Using a single common WHERE condition for UNION in SQL

I am trying to do something like this:

SELECT a.date AS EnrollDate, a.id, a.name, b.address FROM student a JOIN Location b ON a.id=b.id  
UNION  
SELECT a.date AS EnrollDate, a.id, a.name, b.address FROM teacher a JOIN Location b ON a.id=b.id  
WHERE a.date>'2010-01-01'  
ORDER BY EnrollDate

But the WHERE condition applies to the second SELECT statement only. I need to somehow apply to both the SELECT. The only option I have now is to apply WHERE condition individually. But I am working with several UNIONs and it is kind of tedious to include WHERE in all the places. I was wondering if there is an easy way out.

By the way, I am working with MySQL.