I live on the northern coast of California (80 miles south of the Oregon border) within 100 yards of the Pacific Ocean, and I have an uninsulated space under my house which I use as a wine cellar. After living here for close to 20 years, I decided to check out just what the temperature and humidity really were over a year’s period. I started tracking in June of 2017, and have just finished getting the results. Here is what I found:
Average yearly temperature: 58.84 degrees F
Average yearly humidity: 74.66%
Highest average monthly temperature: 65.5 F (September 2017)
Lowest average monthly temperature: 53.9 F (March 2018)
Highest daily temperature: 71 F (Sept. 2, 2017) This was 4 F warmer than the next highest day).
Lowest daily temperature: 51 F (3 days in late February and early March 2018)
Average temperature and humidity:
June 61.6 F, 76.4%
July 62.5 F, 75%
Aug 62.3 F, 75.7%
Sept 65.5 F, 76.7%
Oct. 60.6 F, 74.6%
Nov 57.6 F, 76.1%
Dec 55.6 F, 71.8%
Jan 57.4 F, 77.3%
Feb 54.5 F, 67.7%
Mar 53.9 F, 73.5%
Apr 56.4 F, 74.6%
May 58.2 F, 76.6%
I did not take readings everyday (at least 5 readings per month, and some months with 15 readings), and while I’m not thrilled with the September readings, in general I’m happy with the results for wine storage. Any thoughts?
Any daily temperature variation records? If 71F was 4d higher than the next day, how big is the temp variation over the course of the day? That would worry me a bit, but the highs and lows overall are probably fine
The Sept. 2nd reading of 71 F is 4 degrees higher than the Sept. 3rd reading of 67 F, but other than that one day, I’ve never seen a more than 2 F difference on a daily basis. Generally (probably 90% of the time) the temp difference daily is no more than 1 F.
How great to get some numbers – a couple of months ago I set up gauges for a similar experiment. I’m in L.A. with an uninsulated basement that has so far not seen anything over 68 degrees, but I’m not counting on that holding much longer.
You’ve been there 20 years – how have the wines held up so far?
The air temperature, obviously, changes much more quickly than the bottle temperatures, particularly if the wine is in enclosed cases. And there’s a lot of thermal mass. So I wouldn’t worry much about day-to-day temperature swings. The monthly averages are probably more meaningful, I’d guess.
I started keeping track of similar numbers in a space that will soon become my wine cellar at home. It’s on the first floor, but the floor is the relatively cool concrete foundation and it only has one exterior (shaded) wall. I also live in a very moderate environment (near SF).
So far, the nadir temperature was 51 degrees in February/March, and it has been slowly warming since then. We had a day or two > 80 degrees that it handled very well (<60 degrees in the “cellar”), but then I think the ground has warmed up a tad. It’s now been 60-64 degrees through May with outside temperatures up to 80-84 degrees (usually only for a day or two at a time).
I expect it may warm up another few degrees through the summer, but I’ll be happy if it stays <70 degrees. For what it’s worth, I do plan to put in a cooling unit to keep the temp at 60 in the summer, and then passive in the winter, for my peace of mind.
I have a passive cellar in my insulated crawl space in AK. My annual temperature range is ~56 - 63. My warmest temps are in the winter when the furnace is running because the ducting runs in the crawlspace. My humidity is way lower but after 30 I have noticed no ill effects of low humidity.
I had a storeroom in a basement in SF for 10 years from 1983-93 where I kept my wines. One wall was mostly subground. The others were thin, wood slats adjoining other storerooms and a hallway. So, basically, zero insulation. The air temperature got up into the 70s in September in October, and stayed in the high 50s and 60s the rest of the year, with wide swings day to day. (When the heat was off on winter days, the apartment was probably in the 50s!) I still have wines from that time and they’ve all been fine.
And, in the “let’s not get too neurotic” department, I opened a 1990 Dom Perignon on Thursday. It was given to me on New Years 1998-99 and for several years it was kept in a mini-storage room that did not live up to promises that it would be kept under 65F. In fact, the space stayed in the high 70s all summer for three years. Since 2001 the bottle has been in a kitchen wine cabinet that I keep at 60F. I expected the bottle to show signs of poor storage. Instead, it was fresh, round, and utterly lovely. I served it blind and no one imagined it was anywhere near 28 years ago.
So… don’t lose sleep if you’re cellar doesn’t stay at 55F +/-1 degree.
Following up on Anton’s post, was this air temp, or a bottle probe? If air temp, I’d expect in bottle liquid temp to be less by probably a few degrees.
