Modesto weather in August

In August, Modesto has daytime highs averaging 35 °C, nights around 18 °C, with 0.1 wet days. Figures are 1991–2020 climate normals.

  1. Jan
  2. Feb 11°
  3. Mar 13°
  4. Apr 16°
  5. May 20°
  6. Jun 24°
  7. Jul 26°
  8. Aug 26°
  9. Sep 24°
  10. Oct 19°
  11. Nov 13°
  12. Dec

Daily temperatures through August

14° 26° 38° 18152229
Daily high Daily low Day of month on the horizontal axis. Highs peak at 35.8 °C and lows bottom out at 16.9 °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 34.9 °C 17.7 °C 0 %
11–20 August 35.3 °C 17.9 °C 0 %
21–31 August 34.4 °C 17.5 °C 1 %
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 20, at 3 %. Single dates are noisy — read the shape, not the spikes.

What to expect

Measure Typical August Share of the month
Days above 25 °C 31 of 31 100 %
Days above 30 °C 30 of 31 96 %
Days below 0 °C 0 of 31 0 %
Days with more than 1 mm rain 0.1 of 31 0 %

Conditions in August

MeasureAverage
Mean temperature 26 °C
Record high (1991–2020) 45 °C
Record low (1991–2020) 12 °C
Relative humidity 43 %
Wind speed 15 km/h
Cloud cover 10 %

Where Modesto ranks in August

Ranking Position Value
The driest places in North America in August 12th of 50 0.8 mm
The warmest places in North America in August 20th of 50 35 °C

August compared with the months around it

Month Avg high Rainfall Cloud
June 33.2 °C 3 mm 18 %
July 35.8 °C under 1 mm 10 %
August 34.8 °C 1 mm 10 %
September 32.2 °C 2 mm 13 %
October 26.3 °C 21 mm 25 %

See all twelve months for Modesto

QuestionsAugust in Modesto, answered

How warm is Modesto in August?

Daily highs average 35 °C and nights fall to about 18 °C, a spread of 17 °C between afternoon and dawn. That makes August the 2nd warmest month of the year here.

Does it rain much in Modesto in August?

August averages 1 mm of rain, spread over about 0 of the 31 days — 0 % of the month. Cloud cover averages 10 % of the sky.

How long are the days in August?

Modesto averages 14 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.