Weather in Hermosillo in July

The month to avoid. Of the twelve, July is the one to avoid. Daytime highs average 37.4 °C and the afternoon is not negotiable — outdoor plans move to early morning or evening.

July ranks 12 of 12 — near the bottom of Hermosillo's year. December is the month that works, and the swing between the two is 74 points, which is a different holiday rather than a slightly better one.

Rain on 15 days, 4 of them heavy. Enough to need a plan B, not enough to need a plan around it. Pack for heat management rather than style: shade, water, and a schedule that gives up on the middle of the day.

What the averages hide

Averages flatten a month, and this one hides a few things: 22 days of the month clear 35 °C — that is not a heatwave, it is the month. Across the twenty years measured, the hottest July day reached 48.4 °C and the coldest night fell to 20.2 °C, and the wettest single day dropped 40 mm — roughly 36% of the month's rain in one day.

July is statistically steady but not small: the year-to-year variation is modest in relative terms, yet the wettest July on record still delivered 152 mm against 56 mm in the driest. In a month this wet, even a tame spread is a lot of rain in absolute terms — the 110 mm average is a reasonable planning figure, not a promise.

Wind is light at 8.6 km/h, so the temperature on the page is close to the temperature on your skin, and humidity is unremarkable at 53%.

How July sits in the year

Temperatures hold steady either side: 39.7 °C in June, 37.4 here, 36.8 in August. Nothing about the timing within the month matters much. Rain has already shifted: 13 days more than June had.

Daylight in July

July is at or near the longest days of Hermosillo's year: 13.8 hours of daylight, losing 0.4 hours across the month. Evenings are the real gain — dinner outdoors still happens in full light.

An inland climate

With no coast nearby, the year swings a fair way — 30.1 °C between the warmest afternoons and the coldest nights, wider than any coastal city at this latitude would manage.

How busy it gets

Off season. The genuine off season: cheapest by a distance, with the caveat that some tours and restaurants close entirely.

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

July in Hermosillo versus nearby

If Hermosillo is one option among several, the nearby comparison is worth making. Tucson is close enough to be a coin toss — within a degree on temperature, 2 days more rain. Chihuahua is a better bet in July — 5.4 °C cooler, 1 day more rain.

So: July is a compromise. December is 74 points better and is what Hermosillo 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 Hermosillo

See all twelve months in Hermosillo, or where else to go in July.