Clayton climate

Clayton Weather in May

NOAA 1991-2020 normals for Mt Diablo Junction, 6.9 km from Clayton

Average highs run from 65°F on May 1 to 71°F on May 31, and lows from 47°F to 52°F. Normal precipitation for the month is 1.13 in over about 4 wet days.

May day by day

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

Normal daily high and low temperature at Clayton, in °F, with the record for each date.20406080100120151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

May at a glance

Average high
68°F
Average low
49°F
Precipitation
1.13 in
Record high
105°FMay 31, 2001
Record low
40°FMay 11, 2010
Chance of a freeze
1%
Days of 90°F or more
0.8
Daylight
13 h 48 min to 14 h 37 min
Cloud cover
35%
Humidity
69%
Dew point
48°F
Wind
10.1 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
May 165°F47°F93°F 201443°F 201118%0%
May 265°F47°F93°F 201747°F 201018%0%
May 365°F47°F95°F 201744°F 202217%0%
May 465°F47°F90°F 201346°F 202317%0%
May 566°F47°F93°F 202144°F 202417%0%
May 666°F48°F90°F 200144°F 201016%0%
May 766°F48°F95°F 200146°F 201016%0%
May 866°F48°F96°F 200145°F 201516%0%
May 966°F48°F92°F 202543°F 200315%0%
May 1067°F48°F95°F 200143°F 202215%0%
May 1167°F49°F93°F 202140°F 201015%0%
May 1267°F49°F88°F 201445°F 202215%0%
May 1367°F49°F93°F 201448°F 200814%0%
May 1467°F49°F96°F 201446°F 201114%0%
May 1568°F49°F99°F 200845°F 201114%0%
May 1668°F49°F102°F 200845°F 201114%0%
May 1768°F50°F101°F 200949°F 201113%0%
May 1868°F50°F95°F 201648°F 200313%0%
May 1968°F50°F95°F 200148°F 201113%0%
May 2069°F50°F97°F 200147°F 201013%0%
May 2169°F50°F100°F 200048°F 200912%0%
May 2269°F50°F99°F 200044°F 200212%0%
May 2369°F51°F100°F 200042°F 201012%0%
May 2470°F51°F98°F 202249°F 201111%0%
May 2570°F51°F99°F 202048°F 201011%0%
May 2670°F51°F102°F 202047°F 201111%0%
May 2770°F51°F100°F 202047°F 201010%0%
May 2870°F51°F98°F 200345°F 201010%0%
May 2971°F52°F96°F 201847°F 20119%0%
May 3071°F52°F101°F 202551°F 20119%0%
May 3171°F52°F105°F 200150°F 20119%0%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Clayton, in percent, and of at least 0.1 inch of snowfall.051015201102030
  • Chance of a wet day
  • Chance of snowfall

Sunrise and sunset

Times for 2026, local time (PDT).

May 1
sunrise 6:11 AM, sunset 7:59 PM
May 31
sunrise 5:47 AM, sunset 8:24 PM

Every day of May: 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.