When is it disliked to perform voluntary (Nafal) prayers after the true dawn (Fajr Sadiq) rises?

Prohibited and Disliked Times of Prayer (الأوقات المكروهة)

• Only after the sun rises.
• At all times, except for the two Sunnah rak'ahs of Fajr.
• Nafal is never disliked in the morning.
• Only during cloudy days.