Find the next occurence of a day of the week in postgresql

pg_nextdowinstance.sql

-- I'd gladly pay you Tuesday for a hamburger today!
-- OK, see you next Tuesday.

SELECT * 
FROM generate_series
(
    current_date + '1 day'::interval, -- in case now() is same dow
    current_date + '7 days'::interval, 
    '1 day'
) as s(a)
WHERE 
(select EXTRACT(ISODOW FROM s.a)) = '2';