Weather wise, this doesn't look like the best weekend to tour Napa Valley. Nonetheless, the valley during a storm does have its advantages - less traffic on the main route between Napa and Calistoga, Highway 29; fewer people shouldering up to the winery tasting counters; easier parking for visiting boutiques and galleries along Main Street in St. Helena; and more open tables at the enclave's popular restaurants.

We were reminded of this yesterday, when despite frequent showers and cold winds we nevertheless spent a leisurely day among shops, wineries and restaurants, most notably Mustards Grill, the landmark bistro along the west side of Highway 29 just north of Yountville.

Mustards Grill was an early player in the evolution of Napa Valley into a diner's paradise. This June, it will celebrate its 25th anniversary. That's a heck of a milestone in an area so dependent on fickle shifts in tourism, especially during the winter months. Yet, it was pretty busy last night despite a steady downpour throughout our dinner.

More significantly, Mustards Grill is maintaining the high standards with which it began its long and happy run. The wine list still is enthralling, and the straight-forward contemporary grill food remains fresh, accessible and imaginative. (We won't quibble about the service, which was fine but a bit blunted compared to what we've experienced in the past.)

Some recommendations: The sweet, smoky and spicy chipotle-rubbed quail with cippolini onions ($22.75), the buoyant potato gnocci with a sweet dice of roasted celery root ($18.95), the sunny sweet-corn tamales with wild mushrooms, pumpkin seeds and a salsa of tomatillos and avocado ($10.50), and the substantial grilled-swordfish tostada ($24.95).

Some other recommendations: Take an umbrella, make a reservation at (707) 944-2424, and if you can't get into Mustards Grill consider another of Cindy Pawlcyn's Napa Valley restaurants, Go Fish, the subject of my dining column in this Sunday's Ticket+ in The Bee.