I would like to know when the least crowded month to visit would be with relatively good weather. We plan to spend 2 weeks in BA, the falls and Pategonia. Thanks!

We were in Argentina from the beginning of October to the end of December and had great weather with few crowds just about everywhere we went. The exception was Bariloche which we visited at the time some sort of public holiday and the place was awash with partying students!! The areas we visited included Iguazu, BA (the month of Dec), Salta and the Northwest (the highlight of our time there), Mendoza, Bariloche, Puerto Madryn, Patagonia...

I would say that 80% of the time we had blue skies and reasonable temperature. We did experience 4 seasons in the one day when driving through the seven lakes from San martin des Los Andes to Bariloche (inc. snow and hail!) but that really was the exception.
Have fun its a great country

Th best time is our spring, as Crellston said. March could also be a good time, as the locals have ended their holidays.

Have a wonderful time in our great country, as top poster Crellston called it.

I agree with crellston and avrooster... so now you have 3 independent answers

Big Saludos
Alex y Rijkje
San Lorenzo (Salta)

Sorry I saw the smilley I send,I´m not so good in sending a smilley..

I live in the Lakes district of Patagonia year round, my two favorite times are November when the days are warm and the spring flowers in full bloom or April when the fall foliage is at it's peak.

Me too, soulskier .. in BA, fall and spring are wonderful as well.
The time of year the city seems to be least crowded with tourists though, would be our winter... August and September.
There are plenty of tourists here now !

I think the NW is wonderful the whole year... and you can avoid people with a private service or just driving the time people are not in "those" places they are because of the regular tours schedules!. For instance, Humahuaca is full of people at midday! The restaurants are noisy, crowded, the quality of the food and the service is not the same...
Flintstones

Thank you all for your toughtful replies. I am now thinking either April or possibly November. I do remember seeing a post from someone who went in April that there was a lot of smoke from the farmers burning off the fields. Does this usually happen every year in April, and if so beginnig or end?

Hi, Barblab,
The fires were a one-off incident; no need to worry about it. My favorite times in Argentina (where I lived most of my life) are April, and October-November.
Anne

For the falls, though, I'd definitely recommend April, since it can get truly HOT and HUMID in the NE of the country as summer approaches.

That smoke event was so unusual.. and it was the year before last . This past year there were no smoke problems at all. I wish there had been just a little smoke, the mosquitoes don't come around when there is smoke

The smoke problem was only once, evry now and then people say there is smoke but absolutely nothing compared to what happened that year.
I live in Buenos Aires and I think the best time to come is during spring (Sep-Dec) or during summer when most of the porteños are on holiday so the city is not as crowded as it is during the rest of the year.
Bariloche during winter is full of 18 year old student groups, in our country when teenagers finish high school they make this trip to end this stage (the following year they start college). The trip is a tradition, they go skiing, they go dancing every night and they tend to be out of control the whole trip. This is something foreigners should be told,
I hope you have a nice stay in our country!

Sofi, just to clarify when you say winter you are talking Jan-Mar?

Sorry , I meant our winter that is June-August. Actually the main idea of the student's trip is to go and play with the snow, go dancing every day and to be out of control for 10 days!

sofi - good point re the student issue. We were planning to stay for 5/6 days but after 2 days we decided to move on. Good to see people have a good time but some of these students really were a pain. When we went on the cable car they were drinking , shouting and generally misbehaving and making a nuisance of themselves. On a cable car it could have been dangerous. Hopefully it doesn't happen that often.

I'm also considering an adventure group trip to South America in July that would start in Santiago and head to Puerto Varas, Bariloche, Buenos Aires, the falls, Paraty and finally Rio. I'd like to include more of Patagonia as well though this isn't part of the itinerary. Is it a bad call to take this trip in July, or better to wait till it warms up? I have the time now so want to make the most of it, though I'd hate to get only part of the full experience.