Cold Air?

[greenbar]

was going to take the birds training today,after cleaning out the loft ,i said to my self it,s got a bit colder than earlier on,so let the birds out ,to fly round the loft instead,flew for their normal 30mins some a bit longer,stayed in the garden, and watched them,(hawk watch)in this area,the birds never flew more than I would say 50 ft,some times just missing the ariels,scary stuff, do u think it was the cold air, that was keeping them low,s/h went through them and missed, still flew low,