Climate averages 1991–2020
Hermosillo weather
in September.
A very hot, moderately wet month: the 4th warmest and the wettest of the year.
Long-term climate patterns, not a forecast for a particular trip.
September is a very hot month in Hermosillo: daytime highs average 36.0°C and nights cool to about 24.5°C. By daytime temperature it is the 4th warmest of the 12 months.
Expect about 52 mm of rain on roughly 7 days, which makes September a moderately wet month (the wettest month of the year). Daylight, from sunrise to sunset, lasts about 12 h 22 min on an average September day.
The nearest other city in this atlas is Heroica Guaymas (130 km away). In September its highs average 32.7°C, 3.3°C cooler than Hermosillo, with 59 mm of rain.
Among the 153 cities listed in Mexico, Hermosillo ranks 3rd of 153 for the warmest September highs and 13th of 153 for the driest September (rainfall, lowest first). The mean September high of those 153 cities is 26.5°C; Hermosillo is 9.5°C warmer than that mean.
From September to October, average highs fall by 2.8°C to 33.2°C, and monthly rainfall falls from 52 mm to 19 mm.
The annual picture
September in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Hermosillo climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 23.8°C9.4°C | 9.4°C | 12 | 1.6 | 10.511 h |
| February | 25.0°C10.3°C | 10.3°C | 15 | 2.0 | 11.111 h |
| March | 28.5°C12.3°C | 12.3°C | 6.5 | 0.8 | 12.012 h |
| April | 31.7°C14.9°C | 14.9°C | 1.4 | 0.4 | 12.813 h |
| May | 35.2°C18.1°C | 18.1°C | 0.4 | 0.1 | 13.614 h |
| June | 39.1°C23.3°C | 23.3°C | 3.3 | 1.1 | 14.014 h |
| July | 38.3°C26.6°C | 26.6°C | 40 | 7.6 | 13.814 h |
| August | 37.6°C26.6°C | 26.6°C | 51 | 9.8 | 13.213 h |
| September, selected | 36.0°C24.5°C | 24.5°C | 52 | 7.1 | 12.412 h |
| October | 33.2°C19.1°C | 19.1°C | 19 | 2.1 | 11.511 h |
| November | 27.9°C13.5°C | 13.5°C | 13 | 1.5 | 10.711 h |
| December | 23.1°C9.4°C | 9.4°C | 19 | 1.9 | 10.310 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
September in nearby cities
- Heroica Guaymas in SeptemberMexico · 130 kmHigh 32.7°C · Low 27.0°C · 59 mm rain
- Ciudad Obregón in SeptemberMexico · 205 kmHigh 35.5°C · Low 25.1°C · 82 mm rain
- Nogales in SeptemberMexico · 247 kmHigh 30.2°C · Low 17.3°C · 49 mm rain
- Navojoa in SeptemberMexico · 270 kmHigh 35.0°C · Low 25.0°C · 90 mm rain
- Agua Prieta in SeptemberMexico · 284 kmHigh 30.8°C · Low 18.3°C · 30 mm rain
- Tucson in SeptemberUnited States · 348 kmHigh 34.1°C · Low 21.3°C · 25 mm rain
- Cuauhtémoc in SeptemberMexico · 407 kmHigh 22.9°C · Low 12.9°C · 71 mm rain
- Los Mochis in SeptemberMexico · 415 kmHigh 33.3°C · Low 25.6°C · 102 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Hermosillo) is explained once on the Hermosillo year overview and on the Sources, method and limits page.