I started brewing in 1991 but didn't brew at all from November 2007 to July 2013. I've done 46 batches of beer, 5 wines, and 4 ciders since I started back as I'm trying to make up for lost brewing time. Even though I brew outdoors the weather is not an impediment to brewing year round here. In fact I welcome the "cold" in order to lower the ground water temp to make my immersion chiller more effective.
When I wasn't brewing I missed going to brew club meetings like I did when I first started.
After I moved brewing operations out to the garage, I quite brewing pretty much from December through Feb or so. Depending on the wind, I think 20F is about the lowest I liked brewing outside.
Since we upgraded our stove, I can now brew 5 gallons inside during the winter. With the delivery of some 2.5 gallon kegs, I can also brew smaller batches quicker and easier in the warmth of the kitchen. Plus brewing ads moisture to our dry house better than the humidifier.
I've got plans to brew up a few special beers this winter, including one no-boil (really short boil) beer. I did something similar this spring, but ended up having a longer boil than I planned. I want to recreate the basic process but go actual really short boil. Just get hot break and be done. Tons of late hops.
I also have plans to brew up a bourbon IIPA if I can ever get a vessel freed up to hold it.
Winter is my most prolific brewing period here. From about late may onwards minimum temps at night are usually getting over 20*C/70*f. During July to early October they are usually over 30*C with max day time temps around 35 to 39*C ( close to 100*f ) and humidity in the high 80s to mid 90s% from July to late September so maintaining decent fermentation temps is practically impossible for me as I only use the swamp cooler and frozen bottles of water method. Have been thinking about trying some turbo yeast Heat wave to see if that can make some decent beers during the hot months.
I brew through the winter. Yes, it's less pleasant (well, really just the cleanup part), but it's nice being able to chill my wort so incredibly fast (ice-cold groundwater, plate chiller, Chugger pump), even to lager temperatures. I choose my battles (obviously not brewing during a snowstorm or when it's -30°), but if it's a calm, overcast morning, and just around freezing or a little cooler, it's perfect brewing weather.
As long as there's no wind, I'll brew in the cold. The wind ruins a brew day. Last weekend was in the 40s (F) which is nice, but it was windy and was just a miserable brewday. It took about 2.5 hours to finish a 90 minute boil. Flames kept blowing out, propane tanks were freezing up, it wasn't fun. I don't mind it being cold, but it does make cleanup harder when everything starts icing up as you spray it off.