Weather in Salta in September

Prime time. If you get to pick your dates, September is the one. Highs average 29.1 °C, lows 12.7 °C, and rain falls on 1 days — nothing in the month is working against you.

September ranks 5 of 12 in Salta: past the worst of the year but short of June, which is the month to book if the dates are open.

Rain falls on only 1 days, so an itinerary with no wet-weather fallback is a reasonable risk. Pack for 29.1 °C days and 12.7 °C nights; the spread matters more here than any single number.

What the averages hide

Averages flatten a month, and this one hides a few things: 14 days top 30 °C — hot spells arrive, but they break; the day swings 16.4 °C from low to high, which means one bag has to cover both. Across the twenty years measured, the hottest September day reached 40.8 °C and the coldest night fell to 1.5 °C.

September is dependably dry, and that reliability is the point: across the twenty years measured, the wettest September on record still only managed 25 mm, and the driest managed 0 mm. There is no meaningful variability to plan around, which makes this one of the few months anywhere that you can build a fixed outdoor itinerary against without a fallback. The wettest single day in twenty years of Septembers brought 11 mm. Rain simply is not the variable that decides this trip — heat, crowds and cost are.

Wind is light at 9.2 km/h, so the temperature on the page is close to the temperature on your skin, and humidity is unremarkable at 45%.

How September sits in the year

The month is on the way up: 1.8 °C warmer than August, and October adds another 2.4 °C. Late in the month feels noticeably different from the start of it, which is worth knowing if the trip is short.

Daylight in September

11.9 hours of daylight, gaining 0.7 hours across the month. That is between Salta's extremes of 13.7 and 10.6 hours, so days are long enough not to constrain the plan.

An inland climate

Despite being inland, the year stays fairly even: 21.9 °C between the year's warmest afternoons and coldest nights. At 1054 m the air is thin enough to matter — sun that burns faster than the temperature suggests, and nights that cool off quickly. Within September itself the daily swing is 16.4 °C, so mornings and afternoons need different clothes.

How busy it gets

Busy. Popular without being frantic; book the things you care about, improvise the rest.

Crowd levels are estimated from climate desirability and school-holiday calendars, not from visitor numbers.

September in Salta versus nearby

If Salta is one option among several, the nearby comparison is worth making. San Miguel de Tucumán is close enough to be a coin toss — within a degree on temperature, 1 day more rain. Antofagasta is close enough to be a coin toss — 12.9 °C cooler, 1 day less rain.

So: September works, with June the better month by 9 points if the dates can move. If they cannot, nothing here should stop you booking.

Every month in Salta

See all twelve months in Salta, or where else to go in September.