More precipitation falls on Flannigan Township than on 76% of U.S. towns: 48 inches a year
On a normal July day the thermometer tops out near 88°. The seasons are far apart: from a winter night to a summer afternoon the average spans 63°. In July, afternoons here are warmer than in 66% of U.S. towns. The frost-free window for a garden runs roughly April 11 to October 21.
A year in Flannigan Township at a glance
Each month’s typical high and low, and what it brings.
What stands out about Flannigan Township’s climate
Compared with towns across the U.S., with Flannigan Township’s place in Illinois beside it.
What a year in Flannigan Township feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 190 frost-free days a year
In half of years the last 32° night comes by April 11 and the first by October 21. Frost and day counts come from NOAA’s station at Mcleansboro, IL, 9 miles from the town’s center, at about the same height.
The 2023 USDA map puts Flannigan Township’s center in zone 6b: the coldest night of a typical winter, averaged over 1991–2020, reaches about −1°. 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 13 inches of snow a winter
Snow, measured at Mcleansboro, IL, falls mostly in January and December. Precipitation (rain plus melted snow) adds up to 48 inches a year; April is the wettest month and February the driest. Rain or snow falls on about 121 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Flannigan Township
78% of the work is heating. Months averaging under 55° run from November through March.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at Mcleansboro, IL.
Living with Flannigan Township’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
190 frost-free days in zone 6b. The last frost comes by Apr 11 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 21.
Months with highs of 62–84° and lows of 40° or more: April, May, September and October. 12 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Flannigan Township from natural hazards, earthquakes are the largest share (62%); heat waves, cold waves, winter storms and ice storms together are 7%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Flannigan Township and its neighbors
Every town next door is within a degree of Flannigan Township in January and July, closer than the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like Flannigan Township’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 |
|---|---|---|---|---|
| Flannigan Township, IL | 24° | 88° | 48" | 13" |
| Shively, KY | 25° | 88° | 49" | 13" |
| Collegeville, PA | 23° | 88° | 47" | 13" |
| Aurora, MO | 24° | 89° | 47" | 12" |
| Scottsburg, IN | 23° | 87° | 48" | 12" |
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 Flannigan Township averaged 0.9° warmer than the 1900s. The biggest change is in February (+2.1°).
A smaller shift than in 87% 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 Flannigan Township compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Flannigan Township’s place among Illinois’.
Flannigan Township weather by month
Highs, lows and precipitation from NOAA’s grid at Flannigan Township’s center; snow, wet days and snow on the ground from Mcleansboro, IL. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 41° | 24° | 3.4" | 3.7" | 11 | 6 | 27° – 42° |
| February | 46° | 28° | 3.1" | 3.3" | 9 | 3 | 26° – 46° |
| March | 56° | 36° | 4.4" | 2.1" | 12 | 1 | 38° – 59° |
| April | 68° | 45° | 5.4" | 0.0" | 13 | 0 | 50° – 62° |
| May | 76° | 55° | 5.2" | 0.0" | 13 | 0 | 61° – 73° |
| June | 85° | 64° | 4.7" | 0.0" | 11 | 0 | 69° – 78° |
| July | 88° | 67° | 4.0" | 0.0" | 8 | 0 | 72° – 84° |
| August | 87° | 65° | 3.3" | 0.0" | 8 | 0 | 71° – 81° |
| September | 81° | 57° | 3.4" | 0.0" | 8 | 0 | 64° – 75° |
| October | 69° | 46° | 3.6" | 0.6" | 8 | 0 | 53° – 63° |
| November | 55° | 36° | 4.1" | 0.2" | 10 | 0 | 38° – 52° |
| December | 45° | 28° | 3.5" | 3.4" | 12 | 4 | 23° – 46° |
| Year | 66° | 46° | 48.0" | 13.3" | 121 | 14 |
How much a month can swing
A normal is an average. December swings the most: from 1991 to 2020 its average ranged from 23° to 46°. June is the most reliable, staying within 10°.
Where Flannigan Township’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 Flannigan Township’s center.
- Snow: Mcleansboro, IL.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Mcleansboro, IL, 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 Flannigan Township’s climate
What is the weather like in Flannigan Township?
A typical July afternoon reaches 88°, a January night drops to 24°, and about 13 inches of snow falls in a normal winter. Milder January nights than 61% of U.S. towns; hotter July afternoons than 66% of U.S. towns.
How cold does it get in Flannigan Township in winter?
January nights average 24°. About 110 nights a year reach 32° or below and 3 reach 0° or below. In the coldest January of the last 30 years the month averaged 27°.
How much snow does Flannigan Township get?
About 13 inches in a normal winter at Mcleansboro, IL, most of it in January and December, with snow on the ground about 14 days a year.
How hot does it get in Flannigan Township?
July, with a typical high of 88° and a low of 67°. About 43 days a year reach 90° and 1 reach 100° (Mcleansboro, IL).
When is the first and last frost in Flannigan Township?
In half of years the last spring frost (32°) comes by April 11 and the first fall frost by October 21, about 190 frost-free days, at Mcleansboro, IL.
What growing zone is Flannigan Township in?
Zone 6b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −1°.
What is the best time of year to visit Flannigan Township?
By one simple rule (highs of 62–84° and lows of 40° or more), April, May, September and October. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Flannigan Township getting warmer?
Yes: 1991–2020 averaged 0.9° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 87% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Flannigan Township.
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.