Jefferson has chilly winters and warm summers
A typical July afternoon reaches 84°, a January night drops to 18°, and about 17 inches of snow falls in a normal winter.
A year in Jefferson at a glance
Each month’s typical high and low, and what it brings.
What a year in Jefferson feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
17 inches of snow, 41 of rain and melt
June is the wettest month and February the driest. Rain or snow falls on about 98 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
About 179 frost-free days a year
In half of years the last 32° night comes by April 22 and the first by October 17.
Freezing nights by month
Average nights at or below 32°
90° days by month
Average days at 90° or more
Living with Jefferson’s climate
What the numbers mean for a garden, a driveway, a furnace and a free afternoon.
179 frost-free days. The last frost comes by Apr 22 in half of years, so many gardeners wait a week or two past that to set out tomatoes. The first fall frost comes by Oct 17.
About 17" a winter over 7 days with an inch or more, most in January. Snow covers the ground about 26 days a year.
Months averaging under 55° run from October through April. Heating is 86% of the year’s heating-and-cooling load.
About 20 days a year reach 90°, and July afternoons average 84°.
The nicest months are May, June, July, August, September and October.
Parks & trails →Normals are averages. Ice storms, nor’easters, floods and heat waves are on the natural hazards page.
Natural hazards →Jefferson and its neighbors
Union has the coldest January nights next door (17°) and Adams the hottest July afternoons (84°). Tap a town to see its climate.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value. Snow and frost-free days come from the nearest weather station, so neighbors often share them.
Warmer than it used to be
The last 30 years in Jefferson averaged 1.1° warmer than the 1900s. The biggest change is in December (+2.4°).
A smaller shift than in 62% of U.S. towns.
Change by month
How Jefferson compares
Against every U.S. town on TownTapestry, each counted once, with its place in Indiana.
Jefferson weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 33° | 18° | 2.5" | 5.8" | 9 | 11 | 16° – 38° |
| February | 38° | 21° | 2.0" | 3.5" | 7 | 7 | 17° – 39° |
| March | 49° | 30° | 2.8" | 2.5" | 8 | 2 | 31° – 55° |
| April | 62° | 39° | 3.9" | 0.2" | 10 | 0 | 43° – 56° |
| May | 73° | 50° | 4.3" | 0 | 11 | 0 | 55° – 69° |
| June | 82° | 60° | 5.0" | 0 | 9 | 0 | 66° – 74° |
| July | 84° | 63° | 4.6" | 0 | 9 | 0 | 68° – 79° |
| August | 83° | 61° | 4.0" | 0 | 7 | 0 | 67° – 78° |
| September | 78° | 53° | 3.1" | 0 | 6 | 0 | 60° – 69° |
| October | 65° | 42° | 3.2" | 0 | 7 | 0 | 50° – 60° |
| November | 50° | 32° | 3.0" | 0.5" | 8 | 0 | 34° – 48° |
| December | 38° | 23° | 2.5" | 4.7" | 8 | 6 | 17° – 41° |
| Year | 61° | 41° | 40.9" | 17.2" | 98 | 26 |
Heating and cooling a home in Jefferson
86% of the work is heating, so the furnace matters far more than the air conditioner.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. Source: NOAA station normals.
How much a month can swing
A normal is an average. December swings the most: from 1991 to 2020 its average ranged from 17° to 41°. June is the most reliable, staying within 8°.
Common questions about Jefferson’s climate
What is the coldest month in Jefferson?
January, with a typical high of 33° and a low of 18°.
What is the hottest month in Jefferson?
July, with a typical high of 84° and a low of 63°. About 20 days a year reach 90°.
How much snow does Jefferson get?
About 17 inches in a normal winter, most of it in January.
When is the first frost in Jefferson?
In half of years the first 32° night comes by October 17, and the last spring frost by April 22.
What is the rainiest month in Jefferson?
June, with 5.0 inches of rain and melted snow. The year totals 41 inches.
Neighbors talk weather
Gardens, snow, and the best days of the year in Jefferson.
Your answer becomes a post in Town Square.
Temperatures and rainfall come from NOAA’s gridded climate normals for Jefferson itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Delphi 2 N, IN (5 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000. Today’s forecast: National Weather Service.