Im not sure how relevant this is considering they are palms but I have seen pictures of both sabal palmetto and sabal minor and even a sabal causarium growing in seattle albeit quite slowly.

Loblolly pine is not at all prevalent but has made some comparatively big and happy looking examples in western WA. Otherwise you can search the Seattle arboretum to see what it has here:

Living Collection Search | University of Washington Botanic Gardens

And the Portland arboretum here:

Plant Database - Hoyt Arboretum

Note that the Hoyt file displays color photos taken there when species names included within search results are clicked on.

Thats a quite helpful resource, it makes sense to me that there would be happy lobblies as they are probably one of the most adaptable species in the genus

Not in the PNW, but a planted grove of loblollys about 90 yrs old in Fort Frederick, MD a bit NW of their natural range, but obviously doing very well (tallest are at least 100 ft tall). One grows on my lot quite well -- pond pine too.

I think loblollys are something special just in terms of pure adaptability, being able to grow almost to PA, and then surviving in the true tropics of of north queensland australia in plantations (although these have mostly all been replaced by pinus elliottii and or pinus elliottii x pinus caribaea). I can personally vouch for seeing one in the Port St. Lucie area. (and to give prespective this is the area where coconut palms start to become the norm in the landscape).

Just for reference here's the loblolly in Port St Lucie Florida via Google earth. The part I find strange is that it's being used in a commercial planting that far south.

Thanks for the pic, I'd think loblollies aren't common anywhere in parking lot plantings....

Here's my loblolly now which shows how much bigger it is than just a few years ago. It's in hard, rocky clay soil.

It looks good I think loblollies generally look better on clay. Actually these are some loblollies I saw planted at a parking lot of a local cracker barrel I think they are ironically planted for a "northern" look in this location.

Palms, the tree-farms in central VA and southward are there because the soil is so poor that it's not really farm-able (without big fertilizer costs) and the loblollies grow fast and reliably even in that soil. The MD roads dept did some test plantings of loblollies and other species in highway medians here in west MD and the best looking of those after 50 yrs are the loblolly and white pines. Other species like Scots and Austrian pines did not do well. Virginia pines and Virginia junipers (red cedars) did OK, but are rather poor in form.