Yep, its just the way the core of the bale is formed. As you probably know, a hardcore baler starts forming a tight core almost as soon as you start baling. With a softcore, there is no mechanism to pack the core of the baler. In effect, you only have outer forming belts, so when you start baling, you're simply stuffing hay inside a big "drum". It tumbles around inside until you fill the chamber enough that the belts can start turning the hay like a hardcore. The tumbling action is one of the reason I don't like belted softcore bales. You lose alot of leaf between the belts. The enclosed chamber balers like the M&W lose MUCH less leaf than a standard belted softcore.
As for the weather, its been a rough start to winter. Down to -20C and -30C, and we got hit by some heavy snows. My cattle are back close to the yard in a small wintering pasture, but I've still got plenty of hay stacked by my fall pasture, so I'm hauling it home now. As for changing weather, I can't imagine any place having bigger swings than we do. 40F temperature swings are nothing (80F in the day, 40F at night). When fall hits, and spring starts to break, the weather can get real funky. I've seen rain, snow, sun, melting temps, and -30 all in a 24 hour period.
Rod