Weather in Moab in September

A good month. September works. It is not the peak, but nothing about it fights you. Highs average 30.1 °C, lows 15.5 °C, and rain falls on 7 days — nothing in the month is working against you.

September ranks 6 of 12 in Moab: past the worst of the year but short of April, which is the month to book if the dates are open.

Rain on 7 days, 1 of them heavy. Enough to need a plan B, not enough to need a plan around it. Pack for 30.1 °C days and 15.5 °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: 17 days top 30 °C — hot spells arrive, but they break. Across the twenty years measured, the hottest September day reached 40.4 °C and the coldest night fell to 3.6 °C, and the wettest single day dropped 28 mm — roughly 82% of the month's rain in one day.

September is moderately variable: 4 mm in the driest year against 76 mm in the wettest, around an average of 34 mm. Roughly two Septembers in three land near that average, and the third does something else entirely.

Wind is light at 7.8 km/h, so the temperature on the page is close to the temperature on your skin, and the air is dry at 37% humidity, which makes the heat far more bearable than the same figure somewhere humid — and dehydrates you faster than you expect.

How September sits in the year

The month is on the way down: 4.6 °C cooler than August, with October dropping another 8.2 °C. The first week and the last are not the same trip.

Daylight in September

12.5 hours of daylight, losing 1.2 hours across the month. That is between Moab's extremes of 14.8 and 9.5 hours, so days are long enough not to constrain the plan.

An inland climate

With no coast nearby, the year swings a fair way — 39.1 °C between the warmest afternoons and the coldest nights, wider than any coastal city at this latitude would manage. At 1227 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 14.6 °C, so mornings and afternoons need different clothes.

How busy it gets

Shoulder. The value months — prices ease off and you get the place closer to itself.

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

September in Moab versus nearby

If Moab is one option among several, the nearby comparison is worth making. Aspen is a better bet in September — 9.1 °C cooler, 2 days more rain. Park City is a better bet in September — 8.2 °C cooler, the same number of rain days.

So: September is a compromise. April is 19 points better and is what Moab 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 Moab

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