Rio Grande weather in August

In August, Rio Grande has daytime highs averaging 16 °C, nights around 12 °C, with 9.7 wet days, and a sea temperature of 14 °C. Figures are 1991–2020 climate normals.

  1. Jan 23°
  2. Feb 24°
  3. Mar 23°
  4. Apr 20°
  5. May 17°
  6. Jun 15°
  7. Jul 13°
  8. Aug 14°
  9. Sep 15°
  10. Oct 18°
  11. Nov 20°
  12. Dec 22°

Daily temperatures through August

15° 20° 18152229
Daily high Daily low Day of month on the horizontal axis. Highs peak at 17.2 °C and lows bottom out at 11.1 °C.

How August develops

Averages for the first, middle and last part of the month, from daily 1991–2020 normals. Chance of rain is the share of years in which that calendar day recorded more than 1 mm.

Days Avg high Avg low Chance of rain
1–10 August 15.5 °C 11.8 °C 34 %
11–20 August 15.9 °C 12.4 °C 25 %
21–31 August 16.7 °C 12.9 °C 33 %
0% 50% 100% 1 5 10 15 20 25 30
Chance of a wet day (over 1 mm) by date in August. Wettest date over the 30 years: August 9, at 50 %. Single dates are noisy — read the shape, not the spikes.

What to expect

Measure Typical August Share of the month
Days above 25 °C 0.1 of 31 0 %
Days above 30 °C 0 of 31 0 %
Days below 0 °C 0 of 31 0 %
Days with more than 1 mm rain 9.7 of 31 31 %

Conditions in August

MeasureAverage
Mean temperature 14 °C
Record high (1991–2020) 26 °C
Record low (1991–2020) 3.8 °C
Relative humidity 81 %
Wind speed 25 km/h
Cloud cover 56 %

Where Rio Grande ranks in August

Ranking Position Value
The coolest places in South America in August 24th of 50 16 °C
The coolest places in the world in August 43rd of 50 16 °C

August compared with the months around it

Month Avg high Rainfall Cloud
June 16.3 °C 114 mm 59 %
July 15.2 °C 116 mm 58 %
August 16.1 °C 110 mm 56 %
September 17.0 °C 133 mm 60 %
October 19.2 °C 137 mm 62 %

See all twelve months for Rio Grande

QuestionsAugust in Rio Grande, answered

How warm is Rio Grande in August?

Daily highs average 16 °C and nights fall to about 12 °C, a spread of 3.7 °C between afternoon and dawn. That makes August the 11th warmest month of the year here.

Does it rain much in Rio Grande in August?

August averages 110 mm of rain, spread over about 10 of the 31 days — 31 % of the month. Cloud cover averages 56 % of the sky.

Is the sea warm enough to swim in August?

The sea averages 14 °C off Rio Grande in August. Most people find water below 20 °C bracing and above 25 °C comfortable for a long swim; this figure is a monthly surface average, so a sheltered bay on a still afternoon can be warmer.

How long are the days in August?

Rio Grande averages 11 hours between sunrise and sunset in August. Day length is computed from latitude and date, so it is exact rather than modelled — but it says nothing about how much of that time is sunny.

Data sources and method

Normal period
1991–2020
Dataset version
era5-1991-2020-scores1.1
Last processed

Measured values come from ERA5 reanalysis and are reproduced unchanged. Calculated by us: daylight hours, beach and comfort scores, monthly rankings, threshold day counts, chance of a wet day by date, ten-day averages within the month. Full formulas are on the methodology page.

Contains modified Copernicus Climate Change Service information 2026. Neither the European Commission nor ECMWF is responsible for any use that may be made of the Copernicus information or data it contains.