My local supermarket has been carrying this Chardonnay for several months, priced at $9 if you buy any mixed six. I've bought it a few times, but it doesn't appear that I've ever written up any notes on it; time to rectify that.
With annual sales around one million cases, J Lohr is one of the largest wineries in the USA. Their brands range from downright mediocre plonk to some excellent vineyard designate wines, with fruit sourced from Napa, Paso Robles and Arroyo Seco, though sadly not from the Santa Clara Valley.
The Riverstone Chardonnay comes from Monterey's Arroyo Seco AVA. Unlike altogether too much Monterey fruit it doesn't get excessive oak treatment, so the result is a wine that still shows plenty of Chardonnay character. The 2008 won a gold medal at the most recent SF Chronicle tasting.
2008 J Lohr "Riverstone" Chardonnay, Arroyo Seco
Nose shows pear and melon, with notes of lemon thyme and a subtle use of smoky oak. On the palate it's creamy and rounded with plenty of tropical fruit. The acidity is on the light side, but that's to be expected given the target market. Overall it offers very good value at under $10. 88