Jefferson County climate

Jefferson County Weather in May

NOAA 1991-2020 normals for Evergreen, 8 km from Jefferson County

Average highs run from 58°F on May 1 to 70°F on May 31, and lows from 31°F to 40°F. Normal precipitation for the month is 2.49 in over about 10 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
64°F
Average low
36°F
Precipitation
2.49 in
Snowfall
2.7 in
Record high
93°FMay 29, 2003
Record low
16°FMay 2, 2013
Chance of a freeze
99%
Daylight
13 h 53 min to 14 h 46 min
Cloud cover
58%
Humidity
49%
Dew point
32°F
Wind
8.3 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 158°F31°F84°F 202023°F 201329%11%
May 259°F31°F77°F 200616°F 201329%11%
May 359°F31°F79°F 201225°F 200829%11%
May 459°F32°F87°F 201231°F 201329%10%
May 560°F32°F88°F 200028°F 201129%10%
May 660°F32°F83°F 200425°F 199929%9%
May 760°F33°F86°F 202228°F 199930%9%
May 861°F33°F84°F 201129°F 202430%8%
May 961°F33°F81°F 201126°F 201530%8%
May 1062°F34°F87°F 201825°F 201530%8%
May 1162°F34°F86°F 202226°F 199930%7%
May 1262°F34°F83°F 200927°F 199931%7%
May 1363°F35°F85°F 202626°F 200031%7%
May 1463°F35°F84°F 201332°F 200031%6%
May 1564°F35°F82°F 200034°F 201131%6%
May 1664°F36°F84°F 200035°F 201031%5%
May 1764°F36°F84°F 200329°F 199932%5%
May 1865°F36°F89°F 202032°F 201732%5%
May 1965°F37°F91°F 202032°F 201732%4%
May 2066°F37°F89°F 200529°F 200132%4%
May 2166°F37°F88°F 200624°F 200132%4%
May 2266°F38°F90°F 201234°F 202432%4%
May 2367°F38°F86°F 200034°F 201932%3%
May 2467°F38°F85°F 201332°F 200233%3%
May 2568°F38°F88°F 201837°F 200133%3%
May 2668°F39°F90°F 201839°F 199933%2%
May 2769°F39°F90°F 200641°F 200833%2%
May 2869°F39°F90°F 201039°F 201633%2%
May 2969°F39°F93°F 200338°F 201233%2%
May 3070°F40°F90°F 200238°F 201933%2%
May 3170°F40°F92°F 200238°F 200433%1%

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.0102030401102030
  • Chance of a wet day
  • Chance of snowfall

Sunrise and sunset

Times for 2026, local time (MDT).

May 1
sunrise 6:02 AM, sunset 7:55 PM
May 31
sunrise 5:36 AM, sunset 8:22 PM

Every day of May: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00052790 (Evergreen), public domain. Records: NOAA GHCN-Daily, station USW00093067, 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.