Weather in Baton Rouge in September

Shoulder season. September sits in between. You will get good days and you will lose some. Highs average 31.1 °C, lows 20.8 °C, and rain falls on 13 days — nothing in the month is working against you.

September ranks 9 of 12 in Baton Rouge: past the worst of the year but short of November, which is the month to book if the dates are open.

Rain on 13 days, 3 of them heavy. Enough to need a plan B, not enough to need a plan around it. Pack for 31.1 °C days and 20.8 °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: 21 days top 30 °C, making the heat continuous rather than occasional. Across the twenty years measured, the hottest September day reached 38.4 °C and the coldest night fell to 9 °C, and the wettest single day dropped 101 mm — roughly 81% of the month's rain in one day.

September is moderately variable: 21 mm in the driest year against 304 mm in the wettest, around an average of 125 mm. Roughly two Septembers in three land near that average, and the third does something else entirely.

Wind is light at 4.8 km/h, so the temperature on the page is close to the temperature on your skin, and humidity runs at 79%, high enough to notice on the warm days without dominating them.

How September sits in the year

The month is on the way down: 1.7 °C cooler than August, with October dropping another 3.7 °C. The first week and the last are not the same trip. Rain has already shifted: 8 days fewer than August had.

Daylight in September

12.4 hours of daylight, losing 0.9 hours across the month. That is between Baton Rouge's extremes of 14.1 and 10.2 hours, so days are long enough not to constrain the plan.

An inland climate

With no coast nearby, the year swings a fair way — 28.5 °C between the warmest afternoons and the coldest nights, wider than any coastal city at this latitude would manage.

How busy it gets

Quiet. Few other visitors, cheaper rooms, and a real chance some seasonal operators are shut.

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

September in Baton Rouge versus nearby

If Baton Rouge is one option among several, the nearby comparison is worth making. New Orleans is close enough to be a coin toss — within a degree on temperature, 1 day more rain. Jackson is close enough to be a coin toss — within a degree on temperature, 3 days less rain.

So: September is a compromise. November is 24 points better and is what Baton Rouge is actually like at its best — worth moving the trip for if that is possible, and worth adjusting expectations for if it is not.

Every month in Baton Rouge

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