You need to experiment, as there is tons of variation from location to location, but to start, consult something like this: http://bermangraphics.com/digital-ju...ture_small.jpg, and filter accordingly. According to this, you should warm filter your lens by 2000K, so I would try some sort of 85 filter. The 85B warms by 2300K, the 85C by 1700K, and the plain 85 by 2100K. The best option is a color meter, but how many of us actually own one? Not many.
This is by the book, but IME, a heavy 81 series filter (C or D) does the trick OK.