Benton County climate

Benton County Weather in May

NOAA 1991-2020 normals for Prosser, 19.5 km from Benton County

Average highs run from 70°F on May 1 to 77°F on May 31, and lows from 43°F to 51°F. Normal precipitation for the month is 0.88 in over about 6 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 Benton County, in °F, with the record for each date.20406080100120151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

May at a glance

Average high
74°F
Average low
48°F
Precipitation
0.88 in
Record high
105°FMay 26, 1947
Record low
30°FMay 1, 1954
Chance of a freeze
20%
Days of 90°F or more
2.0
Daylight
14 h 23 min to 15 h 32 min
Cloud cover
58%
Humidity
53%
Dew point
42°F
Wind
8.7 mph

Every day of the month

A wet day has at least 0.01 inch of precipitation.

DateNormal highNormal lowRecord highRecord lowChance wet
May 170°F43°F91°F 195730°F 195418%
May 270°F44°F92°F 194633°F 195418%
May 371°F44°F92°F 194535°F 200618%
May 471°F44°F90°F 196634°F 196218%
May 571°F45°F93°F 196634°F 196518%
May 672°F45°F98°F 194735°F 195018%
May 772°F45°F95°F 198734°F 198418%
May 872°F46°F96°F 198733°F 200218%
May 973°F46°F95°F 198733°F 199918%
May 1073°F46°F97°F 194934°F 199918%
May 1173°F47°F98°F 194934°F 199918%
May 1273°F47°F100°F 194938°F 201218%
May 1374°F47°F100°F 194937°F 198318%
May 1474°F48°F95°F 194934°F 195518%
May 1574°F48°F94°F 197339°F 197419%
May 1674°F48°F96°F 200638°F 198319%
May 1775°F49°F96°F 200638°F 197419%
May 1875°F49°F98°F 195637°F 196519%
May 1975°F49°F98°F 195436°F 200319%
May 2075°F49°F101°F 194742°F 195019%
May 2176°F50°F96°F 195839°F 196019%
May 2276°F50°F98°F 195838°F 196018%
May 2376°F50°F100°F 195838°F 196418%
May 2476°F50°F98°F 194739°F 198618%
May 2576°F50°F104°F 194741°F 196418%
May 2676°F51°F105°F 194742°F 196718%
May 2777°F51°F102°F 195839°F 198918%
May 2877°F51°F94°F 195239°F 197617%
May 2977°F51°F101°F 198340°F 195117%
May 3077°F51°F102°F 198640°F 195017%
May 3177°F51°F104°F 198642°F 195017%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Benton County, in percent.051015201102030
  • Chance of a wet day

Sunrise and sunset

Times for 2026, local time (PDT).

May 1
sunrise 5:44 AM, sunset 8:07 PM
May 31
sunrise 5:10 AM, sunset 8:42 PM

Every day of May: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00456768 (Prosser), public domain. Records: NOAA GHCN-Daily, station USC00457015, 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.