Reply #3: Nah. 3500 is the major cut-off.

[politicat]

Boiling point in Globe AZ (3700 feet) is 205.7 degrees F, and that's not really enough to make much of a difference. Bread bakes fine there, and the crumb on cakes works well. The only place to really make changes is in baked goods leavened by baking powder alone. At 3300 feet, you want to reduce the baking powder (if using double acting) by 1/8 of a teaspoon. (Boiling point at 29.71 mb and at 3300 is 208 degrees, so unless the pressure drops dramatically (i.e. storm front coming in) you probably won't notice the difference.)

All sweet things are slightly more concentrated above 3000 feet, so you might want to reduce sugar by 2 teaspoons or a tablespoon, but experiment first.

Yeast is fine, but watch the first couple of loaves and be prepared to do two rises to develop the flavor well.

Humidity can be as much of a bugabear as altitude, though. The Valley is supposedly hot and dry, but the past few years have been damper than ever in the summers. Out in the hinterlands, however is still dry, and you may need to adjust for that more than for the altitude. Adding a little extra water to breads and quick breads and a little extra oil to cakes helps the moisture content. And trash that idea entirely if you're going with a swamp cooler - then you may need to add extra flour in the summers to compensate for the extra moisture the flour will absorb from the higher humidity.

But no, you probably won't have any disasters. Even the most delicate egg-leavened sponge cakes (like genoise) taste good, though they may be a little odd shaped. That's what frosting's for, though. It fills in the dip in the middle. And if the cake can survive a 9x13 pan, it will bake up fine in anything.