My product rotation is alittle crazy right now because I'm experimenting with a few since the weather will be changing soon. Last year, I moved back into the D.C. area from Chicago, and my hair had to get used to it. Products that worked out there didn't work as well down here, or actually worked better because the water here isn't a hard. Plus, my hair is in better condition(I think), so I may not need to use heavy conditioners like I did last spring/summer.
But the products I use consistently are: Mastey Traite Shampoo(once a week, or as needed), Tigi Moisture Maniac or Elucence as my conditioner/rinse, and Elucence (or Paul Mitchell the Conditioner) as my leave in. I generally like to just go with a leave in and no styling products, but during the warmer months, I will definitely need to use a cream or gel with some hold if I don't want to rewet my hair. I really like using the blue Fantasia IC. It gives excellent, but flexible hold, and should hold up to DC humidity. Since it's not a huge investment, I would try it out.
Do you have a satin pillowcase? This helps preserve my style and prevents my hair from being dried out. If my hair is alittle smushed in the morning, I just spritz with a water/conditioner combo, fluff and go.
If you can, post some pics of your hair so that we can give more product recs.