Never mind that a wine cave has a comparatively comfy ambient temperature compared to the chilly outdoors. We'd like to warm our hands by a nice, crackling fire when we venture out for holiday winetasting in Sonoma and Napa counties, please, Spare the Air day or not! That's no problem at Fritz Underground Winery, because the wood stove in the corner is the only form of heat—besides warming sips of brambleberry-fruited Zinfandel. 24691 Dutcher Creek Road, Cloverdale. Daily, 10:30am–4:30pm. $10–$15 fee. 707.894.3389.
Fires both inside and out flare up with a flick of the switch at Dutcher Crossing Winery—gas-fueled, they can be depended upon during any cold snap. The wide variety of wines is dependably good, too. 8533 Dry Creek Road, Healdsburg. Daily, 11am–5pm. Tasting fee $5; $10 option weekends. 866.431.2711.
Looming like some northern fishing lodge in the mist, Lambert Bridge Winery would just have to sport a grand old hearth stocked with hours' worth of firewood. And so it does, except on Spare the Air days, when a heater fills in. The glow of chandeliers in the redwood cellar creates a scene of rustic warmth, in any case. Suave Sauvignon Blanc, Zinfandel, Cabernet Franc. 4085 West Dry Creek Road, Healdsburg. Daily, 10:30am–4:30pm. Tasting fee $15–$25. 707.431.9600.
Bless humble Mill Creek Vineyards, where all the wines are above average. A wood-burning stove makes the tasting room a toasty spot to sip award-winning Gewürztraminer, and they are technically allowed to use it on Spare the Air days but often choose not to "flaunt that." 1401 Westside Road, Healdsburg. Daily, 10am–5pm. Tasting fee, $5–$10. 707.431.2121.
With free sparkling winetasting, it's Christmas every day at Korbel Champagne Cellars. During the holiday season, there's also a tree with all the trimmings, and a gas fire going, too. 13250 River Road, Guerneville. Daily, 10am–4:30pm; tours, 11am–3pm. 707.824.7317.
Stare down a portrait of "the Count" from a comfy chair in front of the mantel at Buena Vista Winery. For those who like historical restorations, now is a great time to revisit this place, filled with artifacts and lore. Watch for the crocodile. 18000 Old Winery Road, Sonoma. Daily, 10am–5pm. Tasting fee, $10; Saturday tour, $20. 800.926.1266.
Gas hearths blaze away at mid-day at small plate mecca Ram's Gate Winery, 28700 Arnold Drive, Sonoma. Thursday–Monday, 10am–6pm. $15–$20. 707.721.8700.
At bubble palace Domaine Carneros, the wood-burning fire is for members, only; all others may enjoy toasted almonds and Le Rêve Blanc de Blancs in the gassy way. 1240 Duhig Road, Napa. Tastings $20-30. Daily, 10am–5:45pm. 800.716.2788.