The positions specified are for the 1st day of the given month at about 9PM. This should apply to the whole month for all of the planets except perhaps Venus, which moves very quickly.
Month Venus Mars Jupiter Saturn Uranus Neptune Pluto Jan Sgr E Cap Leo Lib Psc Aqr Sgr Feb Aqr E Aqr Leo Sco Psc Aqr Sgr Mar Psc E Cet Cnc Sco Psc Aqr Sgr Apr Ari E Ari Cnc Sco Psc Aqr Sgr May Tau E Ari Cnc Sco Psc Aqr Sgr Jun Gem E Tau Cnc Lib Psc Aqr Sgr Jul Leo E Gem Leo Lib Psc Aqr Sgr Aug Leo E Gem Leo Lib Psc Aqr Sgr Sep Cnc M Cnc Leo Lib Psc Aqr Sgr Oct Leo M Leo Leo Lib Psc Aqr Sgr Nov Leo M Vir Leo Sco Psc Aqr Sgr Dec Vir M Vir Leo Oph Psc Aqr Sgr
Venus is only visible just before the Sun rises or just after it sets. The letter after Venus' constellation refers to when it is visible.
When a planet is on the opposite side of the sky from the Sun from our point of view, it is called opposition. When a planet is at opposition, it is usually at its closest point to the Earth. Since Venus and Mercury are inner planets, they can never be at opposition from our point of view. Mars typically goes into opposition every 25 to 26 months.
Mars does not go into opposition in 2015