We have a pretty high tech humidifier, with special cleaning stuff you use, to avoid the molds and fungus. I am allergic to mold, so this is important. My house is all hardwood, except for the lower level, and it's helped me considerably to sleep in a room without carpeting. The air in my bedroom is usually between 30 and 45% humidity, which is what it takes for me to wake up without feeling like my throat and nose are on fire, when the heat is running. Now, our heat is on a set back to go down to 58 at night, so it's not sweltering, but the heat is drying at any temperature. I don't deal well with high humidity and heat, either and living in Florida sucked for me.
Emily, the thinking about moving to Arizona has certainly changed since the 60s. Think of hundreds of thousands of people with asthma moving there, marrying, and now you have a huge gene pool of people genetically predisposed to it. Factor in people who felt a need to bring non-indeginous plants to the desert and change the landscape and environment by building fake lakes. Then add in over building and growth and natural geography that traps pollutants in the Valley during the winter months (smog) and keeps temperatures above 100 degrees at night, for 3-4 months of the year. The dry air and desert spores complete the picture.
I like the feel of exercising in dry weather, but when it's cold or not above 70. Combine that with 110+ degrees, and well, if you are sane, you are not exercising outside! Don't get me wrong, I enjoy going back for a little vacation in the winter every so often, but it's really nice not to have be on a nebulizer every 4 hours.