It is raining very hard today and I thought you might like to know more about how the ferias (the street markets) work in inclement weather. Some of the small merchants might not set up their stand when its raining hard (like today) but, the big successful ones have tarps over their stands. These tarps also cover the walkways in front of their stands.
So, you can come with your umbrella to protect yourself as you walk to and from the market, but you are mostly covered when you are buying your produce and walking from one stand to the next.
During cold weather (yes, Montevideo has cold, humid weather in the winter), the fruit and vegetable stands are set up for business as usual. You will not find as many summer vegetables during the winter, but some local farmers are now growing fresh vegetables under plastic sheeting roofs over parts of their gardens during the winter months.
Of course there is always a supply of green onions, and cool weather crops (spinach, lettuce, leeks, celery, cabbage, broccoli, and cauliflower). Winter is the season for citrus fruits and winter squash, so they are in plentiful supply in the cold months. And, they use cold storage for many 'fresh' fruits and vegetables like apples, onions, carrots, potatoes, sweet potatoes, and the like.
If you like vegetables and fruits, the weekly ferias are the place to go for your produce. They are there all year round and in all kinds of weather. Maybe I'll see you there.