Table Comments

I saw in the documentation for PostgreSQL that I can add 'comments' to
table entries when creating columns:

http://www.postgresql.org/docs/8.1/static/tutorial-table.html

CREATE TABLE weather (
    city            varchar(80),
    temp_lo         int,           -- low temperature
    temp_hi         int,           -- high temperature
    prcp            real,          -- precipitation
    date            date
);

I did a search and don't understand in what aspect are the 'comments'
relevant / visible? I don't see the comments when I attempt to list /
describe the table with \d weather;

Any suggestions?