ernie in Berkeley wrote:I'd really try to keep them hanging for a while longer, to let the acid decrease. Acid decreases as sugar increases, and even at 25 brix you'll get better balance and riper phenolics. How much rain do you expect? As I recall, SLC gets some showers but dries up quickly this time of year.
You should not add SO2 until after the fermentations are complete.
f the grapes are healthy and nutrition is balanced, starting the primary shouldn't be much of a problem--I used to get 2.9 regularly in the Finger Lakes, often with lower than 23 Brix.