Danville climate

Danville Weather in September

NOAA 1991-2020 normals for Mt Diablo Junction, 8.8 km from Danville

Average highs run from 82°F on September 1 to 77°F on September 30, and lows from 61°F to 58°F. Normal precipitation for the month is 0.12 in over about 1 wet days.

September day by day

The normal high and low for each date, and the record, in °F.

Normal daily high and low temperature at Danville, in °F, with the record for each date.406080100120151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

September at a glance

Average high
80°F
Average low
60°F
Precipitation
0.12 in
Record high
112°FSep 5, 2022
Record low
45°FSep 29, 2007
Chance of a freeze
0%
Days of 90°F or more
5.8
Daylight
12 h 59 min to 11 h 49 min
Cloud cover
18%
Humidity
59%
Dew point
49°F
Wind
9.2 mph

Every day of the month

A wet day has at least 0.01 inch of precipitation; snow means at least 0.1 inch of snowfall.

DateNormal highNormal lowRecord highRecord lowChance wetChance of snow
Sep 182°F61°F111°F 201752°F 20082%0%
Sep 282°F61°F110°F 201750°F 20122%0%
Sep 382°F61°F106°F 201752°F 19992%0%
Sep 482°F61°F103°F 202252°F 19992%0%
Sep 582°F61°F112°F 202252°F 19992%0%
Sep 682°F61°F112°F 202249°F 20012%0%
Sep 782°F61°F112°F 202052°F 20012%0%
Sep 882°F61°F111°F 202252°F 20012%0%
Sep 981°F60°F104°F 201553°F 20022%0%
Sep 1081°F60°F105°F 201551°F 20002%0%
Sep 1181°F60°F102°F 201552°F 20002%0%
Sep 1281°F60°F100°F 200352°F 20053%0%
Sep 1381°F60°F100°F 201950°F 20053%0%
Sep 1481°F60°F99°F 201951°F 20013%0%
Sep 1580°F60°F95°F 200451°F 20123%0%
Sep 1680°F60°F94°F 202549°F 20063%0%
Sep 1780°F60°F97°F 200051°F 20013%0%
Sep 1880°F60°F103°F 200049°F 20124%0%
Sep 1980°F60°F103°F 200048°F 20014%0%
Sep 2079°F60°F99°F 201548°F 20014%0%
Sep 2179°F59°F102°F 201549°F 20044%0%
Sep 2279°F59°F102°F 200350°F 20014%0%
Sep 2379°F59°F99°F 202450°F 20174%0%
Sep 2478°F59°F101°F 201948°F 20055%0%
Sep 2578°F59°F99°F 201948°F 20055%0%
Sep 2678°F59°F102°F 200947°F 20135%0%
Sep 2778°F58°F100°F 200948°F 20135%0%
Sep 2877°F58°F103°F 201049°F 20135%0%
Sep 2977°F58°F100°F 201045°F 20076%0%
Sep 3077°F58°F97°F 201246°F 20076%0%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Danville, in percent, and of at least 0.1 inch of snowfall.02461102030
  • Chance of a wet day
  • Chance of snowfall

Sunrise and sunset

Times for 2026, local time (PDT).

September 1
sunrise 6:38 AM, sunset 7:37 PM
September 30
sunrise 7:03 AM, sunset 6:52 PM

Every day of September: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00045915 (Mt Diablo Junction), public domain. Records: NOAA GHCN-Daily, station USW00023254, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.