Jefferson County climate

Jefferson County Weather in May

NOAA 1991-2020 normals for Hamer 4 Nw, 16.7 km from Jefferson County

Average highs run from 65°F on May 1 to 74°F on May 31, and lows from 32°F to 41°F. Normal precipitation for the month is 1.47 in over about 7 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 Jefferson County, in °F, with the record for each date.020406080100151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

May at a glance

Average high
70°F
Average low
37°F
Precipitation
1.47 in
Record high
94°FMay 28, 2003
Record low
17°FMay 5, 1982
Chance of a freeze
100%
Daylight
14 h 11 min to 15 h 14 min
Cloud cover
65%
Humidity
56%
Dew point
34°F
Wind
7.6 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°F32°F82°F 198119°F 197222%
May 266°F33°F84°F 198518°F 201322%
May 366°F33°F85°F 196622°F 201922%
May 466°F33°F86°F 196622°F 200123%
May 567°F34°F85°F 196617°F 198223%
May 667°F34°F86°F 199225°F 200123%
May 767°F34°F86°F 199222°F 201023%
May 868°F35°F84°F 198724°F 200223%
May 968°F35°F87°F 195421°F 200223%
May 1068°F35°F88°F 202522°F 202223%
May 1169°F36°F87°F 194924°F 199923%
May 1269°F36°F87°F 200124°F 195323%
May 1369°F36°F88°F 201325°F 200923%
May 1470°F37°F86°F 198427°F 195123%
May 1570°F37°F88°F 195427°F 198624%
May 1670°F37°F93°F 196423°F 197424%
May 1770°F38°F87°F 200627°F 198324%
May 1871°F38°F89°F 200925°F 200324%
May 1971°F38°F89°F 195419°F 200324%
May 2071°F39°F87°F 195824°F 200324%
May 2172°F39°F88°F 201227°F 200124%
May 2272°F39°F87°F 196729°F 196624%0%
May 2372°F40°F88°F 197925°F 196624%0%
May 2472°F40°F87°F 200126°F 196024%0%
May 2573°F40°F88°F 200325°F 198924%0%
May 2673°F40°F87°F 202225°F 197524%0%
May 2773°F41°F88°F 196629°F 197324%0%
May 2873°F41°F94°F 200330°F 199123%0%
May 2974°F41°F94°F 200331°F 197723%0%
May 3074°F41°F91°F 200331°F 197723%0%
May 3174°F41°F89°F 198628°F 197823%0%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Jefferson County, in percent, and of at least 0.1 inch of snowfall.05101520251102030
  • Chance of a wet day
  • Chance of snowfall

Sunrise and sunset

Times for 2026, local time (MDT).

May 1
sunrise 6:21 AM, sunset 8:32 PM
May 31
sunrise 5:50 AM, sunset 9:04 PM

Every day of May: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00103964 (Hamer 4 Nw), public domain. Records: NOAA GHCN-Daily, station USW00024145, 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.