Weather in Denver in August

Shoulder season. August sits in between. You will get good days and you will lose some. Highs average 31.8 °C, lows 16.5 °C, and rain falls on 13 days — nothing in the month is working against you.

August ranks 8 of 12 in Denver: past the worst of the year but short of October, which is the month to book if the dates are open.

Rain on 13 days, 1 of them heavy. Enough to need a plan B, not enough to need a plan around it. Pack for 31.8 °C days and 16.5 °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: 5 days clear 35 °C, so a serious heatwave is normal rather than notable; the day swings 15.3 °C from low to high, which means one bag has to cover both. Across the twenty years measured, the hottest August day reached 39.8 °C and the coldest night fell to 8.3 °C, and the wettest single day dropped 25 mm — roughly 48% of the month's rain in one day.

August is statistically steady but not small: the year-to-year variation is modest in relative terms, yet the wettest August on record still delivered 102 mm against 18 mm in the driest. In a month this wet, even a tame spread is a lot of rain in absolute terms — the 52 mm average is a reasonable planning figure, not a promise.

Wind is light at 8 km/h, so the temperature on the page is close to the temperature on your skin, and humidity is unremarkable at 46%.

How August sits in the year

The month is on the way down: 1.6 °C cooler than July, with September dropping another 3.7 °C. The first week and the last are not the same trip. Rain is the thing that moves: September brings 7 days less of it, so pushing the dates later buys drier weather.

Daylight in August

13.8 hours of daylight, losing 1.1 hours across the month. That is between Denver's extremes of 15 and 9.4 hours, so days are long enough not to constrain the plan.

An inland climate

With no coast nearby, the year swings a fair way — 37 °C between the warmest afternoons and the coldest nights, wider than any coastal city at this latitude would manage. At 1609 m, altitude is doing as much work here as latitude: thinner air means fierce sun by day and heat that leaves the moment it sets. Within August itself the daily swing is 15.3 °C, so mornings and afternoons need different clothes.

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.

August in Denver versus nearby

If Denver is one option among several, the nearby comparison is worth making. Aspen is a better bet in August — 6.7 °C cooler, the same number of rain days. Moab is close enough to be a coin toss — 2.9 °C warmer, 5 days less rain.

So: August is a compromise. October is 33 points better and is what Denver 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 Denver

See all twelve months in Denver, or where else to go in August.