Winter nights in Harp Township are colder than in 72% of U.S. towns
In July the day’s top temperature is typically 85°. The gap between a January night and a July afternoon is 68°. Precipitation is light here, less than falls on 64% of U.S. towns. Garden chairs stay out from April to June and August to October, the months with highs of 64–84°.
A year in Harp Township at a glance
Each month’s typical high and low, and what it brings.
What stands out about Harp Township’s climate
Compared with towns across the U.S., with Harp Township’s place in Illinois beside it.
What a year in Harp Township feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 181 frost-free days a year
In half of years the last 32° night comes by April 21 and the first by October 20. Frost and day counts come from NOAA’s station at Bloomington 5w, IL, 24 miles from the town’s center, 110 ft higher.
The 2023 USDA map puts Harp Township’s center in zone 6a: the coldest night of a typical winter, averaged over 1991–2020, reaches about −9°. 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 39 inches of rain a year
May is the wettest month and February the driest.
Rain + melted snow by month
Inches of water
Heating and cooling a home in Harp Township
88% of the work is heating, so the furnace matters far more than the air conditioner. Months averaging under 55° run from October 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 Bloomington 5w, IL.
Living with Harp Township’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
181 frost-free days in zone 6a. The last frost comes by Apr 21 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 20.
Months with highs of 62–84° and lows of 40° or more: April, May, June, August, September and October. 15 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Harp Township from natural hazards, river flooding is the largest share (36%); heat waves, cold waves, winter storms and ice storms together are 20%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Harp Township and its neighbors
Every town next door is within a degree of Harp Township in January and July, closer than the 5 km grid can tell apart. 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 Harp Township averaged 1.2° warmer than the 1900s. The biggest change is in December (+2.3°).
A smaller shift than in 60% 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 Harp Township compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Harp Township’s place among Illinois’.
Harp Township weather by month
Highs, lows and precipitation from NOAA’s grid at Harp Township’s center. 1991–2020 normals.
| Month | High | Low | Rain + melt | 30-yr range |
|---|---|---|---|---|
| January | 34° | 18° | 2.2" | 19° – 37° |
| February | 39° | 21° | 1.9" | 18° – 40° |
| March | 51° | 31° | 2.7" | 34° – 55° |
| April | 64° | 40° | 3.9" | 44° – 58° |
| May | 74° | 52° | 4.5" | 57° – 72° |
| June | 83° | 61° | 4.4" | 67° – 76° |
| July | 85° | 64° | 4.1" | 69° – 81° |
| August | 84° | 62° | 3.5" | 68° – 79° |
| September | 79° | 54° | 3.2" | 61° – 71° |
| October | 66° | 43° | 3.3" | 49° – 60° |
| November | 51° | 32° | 3.0" | 34° – 49° |
| December | 38° | 23° | 2.3" | 17° – 40° |
| Year | 62° | 42° | 39.0" |
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 40°. June is the most reliable, staying within 8°.
Where Harp 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 Harp Township’s center.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Bloomington 5w, IL, 24 miles from the town’s center, 110 ft higher; 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 Harp Township’s climate
What is the weather like in Harp Township?
A typical July afternoon reaches 85°, a January night drops to 18°. Colder January nights than 72% of U.S. towns; hotter July afternoons than 51% of U.S. towns.
How cold does it get in Harp Township in winter?
January nights average 18°. About 132 nights a year reach 32° or below and 10 reach 0° or below. In the coldest January of the last 30 years the month averaged 19°.
How hot does it get in Harp Township?
July, with a typical high of 85° and a low of 64°. About 26 days a year reach 90° (Bloomington 5w, IL).
When is the first and last frost in Harp Township?
In half of years the last spring frost (32°) comes by April 21 and the first fall frost by October 20, about 181 frost-free days, at Bloomington 5w, IL.
What growing zone is Harp Township in?
Zone 6a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −9°.
What is the best time of year to visit Harp Township?
By one simple rule (highs of 62–84° and lows of 40° or more), April, May, June, August, September and October. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Harp Township getting warmer?
Yes: 1991–2020 averaged 1.2° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 60% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Harp 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.