There are plenty of really great White Zinfandels in this area, but I don’t think many, or any really, make it very far distribution-wise. Most of the easy to find White Zin is pretty average stuff. So I’d suggest the same as others, a nicer bottle of a different varietal, maybe a Riesling, or even a dessert wine of some kind.
Off the top of my head though, if you are up for scoping out a wine shop or two, or have time to order online, these are some of my favorite white zins-
Pedroncelli - My absolute favorite. Probably my number one summer wine. I usually buy a case in the spring to have on hand on warm summer evenings.
Dashe Cellars - This one is fairly dry, but it’s got a lot of fruit - strawberry, citrus, etc.
Bonterra - Also dry yet fruity. Thinks raspberries and roses.
Truett Hurst - Zippy and vibrant.
Rotta - Fruity, lots of strawberry.
Montevina - It’s just a little too sweet for me, but it is styled more like most of the white zin you’ll find out there, with just a little more…I don’t know…finesse, maybe? Peaches, grapefruit, honeysuckle.
And there are tons and tons of rose wines, vin gris, etc., from all over the globe. Some of those might be right up her alley.