The St. Helena weather is driven by their dry, Mediterranean climate. This means warm, sunny days in the summer with cool evenings. The winters are cool throughout the day with rain from November to March.
The moderate temperatures make it the perfect Napa Valley stop all year long.
What should you wear in Napa Valley? Napa is famous for its upscale appeal. However, you will find that most places are quite casual with many people in jeans, relaxed attire, and canvas or athletic shoes in most tasting rooms.
Some events or activities require a more upscale dress, but they will let you know before you book your tickets.
If you do want to dress up a bit, and act like you are living the high life, go for it. The great thing is that the wineries, and everyone else in the valley, will welcome you if you choose to go casual too.
Read on for more about what to expect with each season including tips on what to pack.
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Springtime in St. Helena means the end of the rainy season. In March, you will still see quite a bit of rain with it tapering off toward the end of the month.
April and May offer a few springtime showers, but they don't last long.
Day time temperatures this time of year range from highs in the mid-60s in March to the upper 70s toward the end of May. Throughout the month, you will find cool temperatures overnight.
March's average lows are in the mid to lower 40s. April is about the same and May is a little warmer with lows in the upper 40s to lower 50s.
You will want to bring along a variety of items that you can layer. Here are just a few recommendations.
1. Long Pants/Jeans: Bring along a couple of pairs of long pants or jeans. This will keep you warm during the cool mornings and evenings. They will also keep you comfortable throughout the rest of the day.
2. Shirts & Sweaters: I recommend bringing along a couple of short sleeved and a couple of light long sleeved shirts with you. You can pair the short-sleeved shirts with a light sweater or jacket. You can start your day with your sweater over your short-sleeved shirt and then remove it as it warms up. You can then wear it again as it cools down as the sun dips below the mountains.
3. Shoes: Bring along comfortable shoes for your stay. If you plan to wine taste all day, you will be on your feet a lot. A nice pair of canvas shoes or athletic shoes is perfect. You can also wear low heel or flat sandals if you want to dress it up a little. Just make sure you can stand in them for up to an hour at a time.
I've also created more detailed pages by month. Click the links below for more details.
As summer arrives, the St. Helena weather starts to warm up during the day. You will find temperatures in the mid to upper 80s most days in and around St. Helena. You will see a few days up into the 90s too.
The nights stay cool and often dip down into the lower to mid-50s. You will find temperatures in the 60s in the evenings, so you are still able to eat outside if you desire.
You will also find that there is very little rain this time of year with only traces on the radar.
1. Shorts/Skirts: During the day, it is often warm enough to wear shorts, skirts, or summer dresses. This will also allow you to taste either indoors or out as you enjoy the warm St. Helena weather in the summer. I typically also bring along at least one pair of long pants in case I am out later in the evening or want to keep a little warmer when I dine outdoors.
2. Short Sleeved Shirts: Bring along some nice short sleeved shirts. Pair these with your shorts to stay comfortable during the day.
3. Light Sweater or Jacket: Although it is summer and the days are warm and sunny, you will find the cool nights might require a light sweater or jacket. I typically throw in a couple of light sweaters that I can easily bring along with me. You will mostly need these in the morning and evening hours. It's also great to bring them along to the tasting rooms in case the air conditioning is too cool for you.
4. Comfortable Sandals or Shoes: You will want to pay special attention to the shoes you bring along. I recommend bringing a couple of pairs of shoes with you. I typically bring along some casual sandals or canvas shoes. I'll switch back and forth to make sure my feet don't tire too quickly.
Click the links below for even more tips and weather averages by month for Napa Valley.
The St. Helena weather in the fall varies quite a bit. September is a little cooler than the summer, but not by much. It is also warmer during the early part of the month and cooler toward the end. The average highs in September are in the mid-80s and the overnight lows around 50.
October cools down quite a bit more with temperatures in the mid to upper 70s during the day. At night, the overnight lows continue to fall and average in the low 50s to upper 40s.
Temperatures in November continue to drop with highs in the mid-60s. Overnight, you will find that it will sometimes dip down into the lower 40s. This is also the start of the rainy season.
1. Jeans/Pants/Shorts/Skirts: If you plan to visit earlier in the season, you can still wear shorts or skirts during the day. Most days are usually warm enough through the middle of October. No matter what time you visit, make sure to bring along at least one long pair of pants or jeans as the nights cool off quickly.
2. Shirts: Bring along cooler, shorter sleeved shirts through mid-October. You will then want to pack light, long sleeved shirts. Even if you plan to visit earlier in the season, bring along at least one long sleeved shirt for the evenings.
3. Sweaters/Jackets: Bring along one to two light weight sweaters or jackets. You will want this throughout the fall season in Napa. Make sure it's something you can layer so you can add and remove them as needed.
4. Shoes: I typically bring along at least two pairs of shoes. I love to bring along low heel or flat sandals toward the beginning of the season. I will also bring some nice canvas or athletic shoes to change into if my feet get too tired.
Click the links below for a more detailed look at the weather in Napa by month. You will also find even more recommendations on what to pack.
The St. Helena weather in the winter offers both cool days and chilly evenings. It's the heart of the rainy season with around seven inches of rain each month.
During the day, the highs are usually in the upper 50s to lower 60s. Overnight average lows hover around 40 degrees with many nights dipping into the upper 30s.
Does in snow in St. Helena in the winter? You will find a light dusting of snow every few years. It isn't common to see an accumulation of snow in the winter, but it does happen a couple of times each decade. It never lasts long though and is a beautiful sight to see if you are lucky!
As the days warm up, the frost or dusting of snow will burn off quickly.
1. Shoes: Bring along two pairs of comfortable close toed shoes. I will bring along flats or some canvas shoes. If you are here for wine tasting, most wineries don't have much seating. You will find yourself standing on cement or wood floors for up to an hour at a time. I like to bring more than one pair of shoes, so I can switch them around to help keep my feet happy!
2. Shirts: Bring along two to three medium weight, long sleeved shirts or sweaters. This will keep you warm during the day as you are wine tasting around Napa Valley.
3. Pants/Jeans/Long Skirts: As it's cool both day and night, you will want to stay warm with long pants or jeans. Long skirts would also work well. This will keep your legs warm and make the wine tasting experience more enjoyable.
4. Jacket: Bring along a light to medium weight jacket for your visit in the winter. It will be really cool in the mornings and you might need it for your first few winery visits. You will then be able to leave it in the car as it starts to warm up during the day. You will also need it again in the evenings as the valley cools down quickly after sunset.
Read on for more details by month with additional tips on what to pack.