I had poor flow today too, though all were flowing, 35 taps, all south facing that gave me 30 gals of sap on sunday, gave me 12 gallons today. (Trees in Middlefield/Durham) I was disappointed with that, I expected more, but the sun wasn't very strong today, Ive always found daily runs to be better (as long as the temp swings are right) on days where the tree trucks warm from solar heat. Were in for a good run by the looks of the next few days forecast… so I wouldn't worry yet. On the down side, I noticed one of my sugar maples has gone yellow already.