Help with Winter Sunrise hat pattern

I knitting the Winter Sunrise hat pattern from Ravelry
(http://www.ravelry.com/patterns/library/winter-sunrise-hat) and I’m baffled because it says to cast on 144 stitches. This sounds like a lot of stitches for a hat, in fact, when I casted on the sts they filled up a 40 inch long circular needle instead of the 16" needle suggested for the hat. The suggested yarn for this hat is a sport weight yarn with 24 sts/4 inches. My yarn is a sport weight yarn with 23/sts/4inches. I used size 4 needles to get the guage. Why did my cast on fill up a 40" needle? Also, the pattern says the guage is 30 sts/4 inches, but the guage of the suggested yarn. What did I do wrong? Does anyone have a suggestion for another fair isle hat pattern where I can use size 4 needles and sport weight yarn?

The stranded work is going to pull in the sts. It may help to try a gauge swatch or to knit several rows on the hat. (I’m not sure how far you’ve gotten.)
The people who have knit the hat seem pretty pleased and some have made several versions.
You can always try an advanced search on Ravelry for Fair Isle and sport weight if you’d be happier moving on.

You cast on so many stitches because fair isle isn’t as stretch as stockinette. You need them to make the hat fit. Now I can’t say that for your personal knitting style you may need a few more or less, but you can’t know that till you try.