PostgreSQL: Query DB for rows containing integer[] > or < than specified value
Assuming your table is named readings:

Find cities where at least one temperature is bigger than 80:

select *
from readings r
where exists (select 1 
              from unnest(r.temps) i
              where i &gt; 80)


Find cities where all temperatures are bigger than 68:

select *
from readings r
where 68 &lt; all (select i
                from unnest(r.temps) i)