WHITE is great for blocking, use a 3M or cheaper powder black guide coat ,works a treat, light blue colour will need a light grey primer or white,why not buy a cheapo fan and paint it inside thats what i do here in Oz,gunna be 2 Deg. Celsius here tonite, in 2 months it will be 46-48 maybe, try and paint when its LESS humid,paint and compressors dont like it...yes i,m a Painter by Trade :)