The likeliest candidate, to my knowledge, for outdoor growth where you are is the Mazari Palm (Nannorrhops ritchiana), which is the hardiest palm in the world. It may not give the effect you want though: mature plants resemble haystacks more than they do other palms. Hope someone has better suggestions.

Kevin : ]

If you want outdoor palm survival, I would plant a larger needle palm on the sunny south side of your home and mulch and cover for winter.

I have seen others in zone 5 have a pindo palm survive by wraping in large Christmas lites and using them when temps drop, also they cover the palm with plastic - keep 'em dry all winter in zone 5. Let them drink in the fall and Spring, Summer of course as well.

I heard of a guy that has a palm in Bountiful UT that keeps his palm (don't know what kind) wrapped in Christmas lights. In St.George UT I have seen Washingtonias and Sabals but I think that area is zone 7. Anyway, I need to think of better palms for pots because they can be moved into my house or greenhouse if need be to hide from the insanely cold winter. I think that my date palms could be ok in the garage on most nights because the water in my carnivorous plant terrarium only freezes a little on even the coldest nights. I'll have to check the temperature some time to see just how cold it gets. When the date palms are ten feet high (wishful thinking no doubt) it might be easier to move them from my garage to the greenhouse on warm winter days and back at night than to go into my home with them. I need to invest in a wagon or wheel barrow. Gosh I miss good old warm NC. I can't wait 'til spring and for my greenhouse to be built.