good stuff. it makes sense (well, as much as it can to someone who only took 3 semesters of college physics lol). i agree that the 500 chart plays a huge role here, at least from experience. i feel like this year we've been lacking with good tracks...for the most part. just not enough cold in general, which makes it even more complicated in march.
long story short, it seems like sun angle would affect the overall environment, but if it's cold it's cold...as psu said before, if it's cloudy there won't be as much of an effect anyway. the problem is that it's just flat out warmer in march (sun angle)...therefore, generally less chances.