First understand that there is no rain from mid-May thru early November. Okay, you might get a tiny bit from mid-May through Mid-July (we did 3-4 times in 2005, but that was unusual), or the rainy season might start as early as mid-October. There are usually a few heat waves, although none in the summer of 2005.
In general, it’s very warm in Napa Valley. The second warmest area is around Healdsburg and the town of Sonoma. (Example: It was over 100 for all Napa and eastern Sonoma County for a week in late June, 2006.) The Sonoma Coast is usually cool to cold, but you never know – it does get into the eighties there – you must always bring warm and cold weather clothes when going to the coast.
Weather forecasts are laughably unreliable for Sonoma and Napa. The term “they haven’t a clue” really applies here.
Worst Months for Rainy Weather: December is the rainiest month, followed by
January (and early February). Note: In 2006, all of February, March and first half of April were heavily rainy and, for the first time in the 7 years, they would have not been good months to visit. The previous six years we’ve been here, the month of March was a perfect time to visit – incredibly beautiful and little rain.
Warmest Months: July, August, September, June, October (perhaps in that order). You can bake during these months, especially in Healdsburg and Napa Valley. It almost always cools off at night.
Worst Month to Visit:
January, especially the first two weeks of January; quite a few restaurants are closed. The last week of December is not the best choice, either.
Worst Day to Visit: Tuesday. More wineries and restaurants are closed on Tuesday than any other day...this makes it a great day to visit San Francisco!
Best Months for Scenic Beauty:
April, Early May, March, Late February (in that order). Some might say all-year-round, but December is not as beautiful as October, for example. With no rain from late May thru at least the end of October, the countryside turns brown (i.e., the unfarmed, non-tree covered hills). The Sonoma coastline is especially beautiful in the Summer, because the flowers along the beach cliffs are in full bloom – like ice plants.
Best Months for Local Produce (which is incredibly great): September, August, July, October, June, May (in that order) – and again, especially in Sonoma County where there are still quite a few farms. Napa agricultural land is almost all used for growing grapes (or olives).
Best days to visit wineries: Friday, Thursday, Monday and Wednesday (in that order). If you love crowds: Saturdays and Sundays. The one benefit of tasting on weekends, is that some wineries open additional wines for tasting on the weekends only. If you intend to do a tour with a winemaker, understand that that's not going to happen during harvest (parts of September and October).
Temperature: Temperatures can have a wide range - Mornings can be foggy in Sonoma, requiring a light coat or sweater and long pants, the same day you may need shorts by mid-day and then long pants and a jacket at night. Think: Very warm days, but nights very from warm to cool - very dependent on exactly where you are (esp. if there's wind or not) and the randomness of the weather.
Fog: This starts in mid-May to early June and ends - ah, I don't know. Only once was the fog so dense that it really slowed traffic (and that was at 4am). So, Fog doesn’t get in the way – it just makes it overcast – mostly west of Hwy 101 in Sonoma County, often until noon in places (and as late as 3pm at times!). This is not an area where fog lights get any use.
Worst time to go:Friday afternoons. Hwy 101 can get horrible, esp. if it’s a big event weekend. Try to avoid driving from San Francisco to Napa or Sonoma on a Friday afternoon (say 2pm until 7pm). Really. If you have to, allow 40-80 minutes extra time to get where you're going.
Worst Time of the Week to Drive to Wine Country: Driving from San Francisco/Bay Area to Sonoma or Napa on Friday afternoons (2-7pm) can be very slow. (The return drive on Sunday afternoons can turn hellacious, too.) Allow for an extra 30 mins or more for the normally 60 minute or so drive. Holidays can be bad, too.
Best Routes: Napa to Calistoga:Silverado Trail.
Healdsburg to Calistoga (and to all of Napa County): Hwy 128 To Lake County: Go to Calistoga and head NE out of town Santa Rosa to Sonoma: Rt 12. More scenic/slower/different: Bennett Valley Rd to Glen Ellen (Yes, a drive through the Bennett Valley appellation.) Actually, the fastest route, particularly from downtown or west Santa Rosa, is Hwy 101 South to Petaluma, Rt 116 to Rt 12. Santa Rosa to Calistoga & St. Helena: Mark West Springs to Calistoga Rd, then Hwy 109 (Depending on where you start, starting from Calistoga Rd in Santa Rosa may be best) Santa Rosa to St. Helena Scenic Route: Calistoga Rd to St. Helena Crossroad Santa Rosa to Oakville & Yountville: Rt 12 to Oakville Crossroad. Santa Rosa to Healdsburg & Geyserville: Hwy 101
Town of Sonoma to City of Napa: Hwy 116 east, then North on Hwy 29 Santa Rosa to town of Napa: Rt 12 to Sonoma, Napa Rd east and back on Rt 12 east. Then North on Rt 29. Napa to Sonoma: Hwy 29 South to Rt121/12 West, then Northwest on Rt 12 (where it splits with 121), to Napa Rd, to Sonoma.
Traffic Bottlenecks: Napa County: Weekends from are far South as Oakville into St. Helena (the North direction) – can be bumper-to-bumper, esp. on event weekends (including the Silver Oak release party). Great alternate route: Silverado Trail Novato Narrows (where 3 lanes goes down to 2): When Hwy 101 goes from 3 lanes to 2, it will back up or be slow during heavy traffic times, like rush hour. Corte Madera to San Rafael (North) during daily rush hour and especially on Fridays. It is particularly bad merging onto HWY 101 in San Rafael from the Richmond Bridge direction. San Rafael (South) in the mornings can sometimes be awful due to early morning fog. Hwy 101 Hill from Petaluma to Cotati (North) can be extremely slow during rush hours. Santa Rosa (North) – Backs up during rush hour. Especially bad between Rt 12 exit and Steele exit. (North & South): Slows during lunch time most every day. When slow it may take 5-10 extra minutes. Hwy 101 (South) from River Road to Santa Rosa – Slows during afternoon rush hours, esp. on Fridays. Hwy 12 from Santa Rosa to Sonoma gets slow at random on the weekends and Friday early evenings. It backs up going into Sonoma at times, starting around Agua Caliente.
Update June, 2006:Mid-Santa Rosa Hwy 101 construction began and will last two plus years. Already very slow at times, it’s just going to be worse.
In San Rafael, they're widening Hwy 101 and there will be delays at times.
Sonoma Coast Note: The windy coast road is very, very slow in places, due to hairpin turns and very little straight roads. Driving from Bodega Bay to Tomales Bay takes a LONG, long time. This is impossible to tell by looking at a map. (Don’t even think you can average 30 mph.)
To Lake County from Napa: The reason why Lake County isn’t too popular, is that getting there is very slow - a windy road leads from Calistoga - it eventually gets up to 40 or so mph. It’s also gets hotter and drier - I still remember seeing desert type plants there, which you don't see in Napa.
Where to see Redwood trees:
• Armstrong Redwood Forest (Giant ones)
• Rt 128 in Anderson Valley as you get near the coast (Giant ones)
• River Road ending before Guernville
• Calistoga Rd (the shady part So. of Porter Creek)
• Sweetwater Springs Rd
• St. Helena Crossroad
• Oakville Crossroad
• Other places (hey, even the road we live on has a few)
• The Sonoma Coast
• Around Lake Beyeressa
• Mendocino via either the coast or the redwood forest (Andersen Valley)
• Oakville Crossroad
• St. Helena Crossroad
• All of the roads to the Sonoma Coast: Skaggs Spring Rd, River Rd (to Jenner), etc.
• Sweetwater Springs Rd
• Rt 29 North from Calistoga (the hilly part)
• Chalk Hill Rd
• Rt 128 from Calistoga to Healdsburg
• Howell Mtn Rd (The hill roads of Napa and Sonoma have a lot charm.)
Speed Traps: You're not likely to encounter a speed trap in Wine Country. But they do exist. The road most often trapped is Fountain Grove Pkwy, a quasi-short cut from Hwy 101 to Rt 12 (indirectly) - be extra-cautious on this road!
Most Dangerous Road:Mark West Springs Rd/ Porter Creek Rd (Santa Rosa area, from Redwood High to Calistoga Rd) - I believe more pedestrians and bicyclists are hit along here than any road in Wine Country.
Not enough roads: As a visitor to wine country, you might quickly notice that we're a bit short of lanes on major roads in Napa and Sonoma, nor is there an Interstate Highway in Wine Country. Unlike elsewhere, when more road is needed it's simply built, here a good number of the locals don't want to see more tourists here and therefore actively hinder the addition of more lanes, etc. This explains why Hwy 29 is one lane through key parts of wine country, and why US 101 is not already three lanes from Novato to Healdsburg.