A middle-of-the-road climate: Humboldt is close to most U.S. towns on every count
January mornings start at about 20°. Winter nights are cold: in January they are colder than in 61% of U.S. towns. December has warmed most since 1901–2000, part of a 1.2° rise. For walks and days out, the stretch from April to June and September to October brings highs of 64–83°.
A year in Humboldt at a glance
Each month’s typical high and low, and what it brings.
What stands out about Humboldt’s climate
Compared with towns across the U.S., with Humboldt’s place in Illinois beside it.
What a year in Humboldt feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 189 frost-free days a year
In half of years the last 32° night comes by April 15 and the first by October 24. Frost and day counts come from NOAA’s station at Mattoon Coles Co Airport, 9 miles from the town’s center, at about the same height.
The 2023 USDA map puts Humboldt’s center in zone 6a: the coldest night of a typical winter, averaged over 1991–2020, reaches about −5°. Plant labels use the zone; frost dates tell you when to plant.
Freezing nights by month
Average nights at or below 32°
90° days by month
Average days at 90° or more
About 15 inches of snow a winter
Snow, measured at Mattoon, IL, falls mostly in January. Precipitation (rain plus melted snow) adds up to 40 inches a year; June is the wettest month and February the driest. Rain or snow falls on about 114 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Humboldt
83% of the work is heating. Months averaging under 55° run from November through April.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at Mattoon Coles Co Airport.
Living with Humboldt’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
189 frost-free days in zone 6a. The last frost comes by Apr 15 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 24.
Months with highs of 62–84° and lows of 40° or more: April, May, June, September and October.
Parks & trails →Of the yearly building losses FEMA expects in Humboldt from natural hazards, river flooding is the largest share (49%); heat waves, cold waves, winter storms and ice storms together are 9%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Humboldt and similar climates
TownRatings has no climate map of the towns around Humboldt yet.
Climates most like Humboldt’s, farther away
TownRatings’ own comparison of NOAA 1991–2020 normals, not a NOAA product: places of 5,000+ at least 150 miles away, one per state, closest on January low, July high, precipitation and snow.
| Town | Jan. low | July high | Precip. | Snow |
|---|---|---|---|---|
| Humboldt, IL | 20° | 86° | 40" | 15" |
| Moberly, MO | 19° | 87° | 42" | 15" |
| Dayton, OH | 22° | 86° | 41" | 12" |
| Fort Madison, IA | 17° | 86° | 39" | 18" |
| Connersville, IN | 20° | 85° | 44" | 16" |
Temperatures and precipitation come from NOAA’s 5 km grid; snow and day counts from the stations named on this page.
Warmer than it used to be
The last 30 years in Humboldt averaged 1.2° warmer than the 1900s. The biggest change is in December (+2.3°).
A smaller shift than in 65% of U.S. towns.
Change by month
The two periods overlap (1991–2000 is in both), which makes the gap a little smaller than it would be between separate periods.
How Humboldt compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Humboldt’s place among Illinois’.
Humboldt weather by month
Highs, lows and precipitation from NOAA’s grid at Humboldt’s center; snow, wet days and snow on the ground from Mattoon, IL. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 35° | 20° | 2.4" | 5.2" | 10 | 8 | 20° – 39° |
| February | 40° | 23° | 2.1" | 3.6" | 8 | 7 | 20° – 42° |
| March | 52° | 32° | 2.8" | 1.9" | 10 | 1 | 35° – 56° |
| April | 64° | 42° | 4.5" | 0.1" | 11 | 0 | 46° – 59° |
| May | 74° | 53° | 4.4" | 0.0" | 13 | 0 | 58° – 72° |
| June | 83° | 62° | 4.8" | 0.0" | 11 | 0 | 68° – 76° |
| July | 86° | 65° | 4.2" | 0.0" | 9 | 0 | 70° – 82° |
| August | 85° | 63° | 3.0" | 0.0" | 8 | 0 | 69° – 79° |
| September | 79° | 56° | 3.0" | 0.0" | 7 | 0 | 62° – 72° |
| October | 67° | 44° | 3.5" | 0.0" | 9 | 0 | 51° – 61° |
| November | 52° | 34° | 3.4" | 0.6" | 10 | 0 | 35° – 50° |
| December | 40° | 25° | 2.4" | 3.1" | 9 | 4 | 18° – 42° |
| Year | 63° | 43° | 40.4" | 14.5" | 114 | 20 |
How much a month can swing
A normal is an average. December swings the most: from 1991 to 2020 its average ranged from 18° to 42°. June is the most reliable, staying within 7°.
Where Humboldt’s numbers come from
Normals are 30-year averages, not a forecast. How TownRatings reads climate data →
- Temperatures and precipitation: NOAA’s gridded 1991–2020 normals for the 5 km cell at Humboldt’s center.
- Snow: Mattoon, IL.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Mattoon Coles Co Airport, 9 miles from the town’s center, at about the same height; the nearest station that passes our checks for distance, height and agreement with the grid.
- Growing zone: USDA Plant Hardiness Zone Map, 2023. USDA Agricultural Research Service and PRISM Group, Oregon State University, prism.oregonstate.edu/phzm, accessed 8 Oct 2026.
- Then and now: NOAA’s gridded normals for 1901–2000 at the same cell.
- Storms and extremes: FEMA National Risk Index (expected annual losses to buildings).
Common questions about Humboldt’s climate
What is the weather like in Humboldt?
A typical July afternoon reaches 86°, a January night drops to 20°, and about 15 inches of snow falls in a normal winter. Colder January nights than 61% of U.S. towns; hotter July afternoons than 54% of U.S. towns.
How cold does it get in Humboldt in winter?
January nights average 20°. About 106 nights a year reach 32° or below and 4 reach 0° or below. In the coldest January of the last 30 years the month averaged 20°.
How much snow does Humboldt get?
About 15 inches in a normal winter at Mattoon, IL, most of it in January, with snow on the ground about 20 days a year.
How hot does it get in Humboldt?
July, with a typical high of 86° and a low of 65°. About 20 days a year reach 90° (Mattoon Coles Co Airport).
When is the first and last frost in Humboldt?
In half of years the last spring frost (32°) comes by April 15 and the first fall frost by October 24, about 189 frost-free days, at Mattoon Coles Co Airport.
What growing zone is Humboldt in?
Zone 6a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −5°.
What is the best time of year to visit Humboldt?
By one simple rule (highs of 62–84° and lows of 40° or more), April, May, June, September and October. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Humboldt getting warmer?
Yes: 1991–2020 averaged 1.2° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 65% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Humboldt.
Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000; USDA/PRISM 2023 hardiness zones; FEMA National Risk Index. Today’s forecast: National Weather Service.