Climate averages 1991–2020
Piedras Negras weather
in September.
A hot, moderately wet month: the 5th warmest and the wettest of the year.
Long-term climate patterns, not a forecast for a particular trip.
September is a hot month in Piedras Negras: daytime highs average 32.8°C and nights cool to about 23.2°C. By daytime temperature it is the 5th warmest of the 12 months.
Expect about 79 mm of rain on roughly 8 days, which makes September a moderately wet month (the wettest month of the year). Daylight, from sunrise to sunset, lasts about 12 h 21 min on an average September day.
The nearest other city in this atlas is Ciudad Acuña (81 km away). In September its highs average 32.3°C, about as warm as Piedras Negras, with 65 mm of rain.
Among the 153 cities listed in Mexico, Piedras Negras ranks joint 11th of 153 for the warmest September highs and 21st of 153 for the driest September (rainfall, lowest first). The mean September high of those 153 cities is 26.5°C; Piedras Negras is 6.2°C warmer than that mean.
From September to October, average highs fall by 4.1°C to 28.7°C, and monthly rainfall falls from 79 mm to 60 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
Piedras Negras climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 19.0°C7.9°C | 7.9°C | 25 | 4.3 | 10.511 h |
| February | 21.9°C10.2°C | 10.2°C | 27 | 4.5 | 11.211 h |
| March | 25.7°C13.9°C | 13.9°C | 43 | 5.6 | 12.012 h |
| April | 29.9°C17.8°C | 17.8°C | 48 | 6.1 | 12.813 h |
| May | 32.9°C21.8°C | 21.8°C | 74 | 8.3 | 13.614 h |
| June | 35.9°C25.0°C | 25.0°C | 46 | 6.1 | 13.914 h |
| July | 36.6°C25.8°C | 25.8°C | 50 | 5.9 | 13.814 h |
| August | 36.8°C26.4°C | 26.4°C | 46 | 4.6 | 13.213 h |
| September, selected | 32.8°C23.2°C | 23.2°C | 79 | 8.3 | 12.412 h |
| October | 28.7°C18.5°C | 18.5°C | 60 | 6.5 | 11.511 h |
| November | 22.9°C12.9°C | 12.9°C | 36 | 4.8 | 10.711 h |
| December | 19.1°C8.5°C | 8.5°C | 27 | 4.5 | 10.410 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
- Ciudad Acuña in SeptemberMexico · 81 kmHigh 32.3°C · Low 22.8°C · 65 mm rain
- Nuevo Laredo in SeptemberMexico · 168 kmHigh 33.2°C · Low 23.7°C · 77 mm rain
- San Antonio in SeptemberUnited States · 213 kmHigh 31.6°C · Low 22.0°C · 77 mm rain
- Monclova in SeptemberMexico · 218 kmHigh 29.5°C · Low 21.1°C · 95 mm rain
- New Braunfels in SeptemberUnited States · 258 kmHigh 31.3°C · Low 21.8°C · 74 mm rain
- San Angelo in SeptemberUnited States · 307 kmHigh 30.6°C · Low 20.0°C · 53 mm rain
- Austin in SeptemberUnited States · 321 kmHigh 31.3°C · Low 21.8°C · 75 mm rain
- Corpus Christi in SeptemberUnited States · 322 kmHigh 30.7°C · Low 23.8°C · 113 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 Piedras Negras) is explained once on the Piedras Negras year overview and on the Sources, method and limits page.