Best Time to See Chiggers in Illinois
May, June and September is the best time to see chiggers in Illinois. Based on 7 verified iNaturalist observations, here is exactly when chiggers are most active across the year in Illinois.
By Tim, founder of Easy Street Markets. I maintain the wildlife database and verify every animal and source myself. Updated July 22, 2026.
Hannemania monticola · Reid Hardin CC BY
7 verified observations of chiggers in Illinois, recorded across 4 months of the year on iNaturalist.
When chiggers are recorded in Illinois
Peak month
May
2 records (28.6% of the year)
| Month | Observations | Share |
|---|---|---|
| January | 0 | 0% |
| February | 0 | 0% |
| March | 0 | 0% |
| April | 0 | 0% |
| Maypeak | 2 | 28.6% |
| Junepeak | 2 | 28.6% |
| July | 0 | 0% |
| August | 1 | 14.3% |
| Septemberpeak | 2 | 28.6% |
| October | 0 | 0% |
| November | 0 | 0% |
| December | 0 | 0% |
Chiggers you are most likely to see
| Species | Verified observations |
|---|---|
| Common Chigger | 4 |
| Hannemania dunni | 1 |
Weather to expect, source Open-Meteo
Typical weather in Illinois
Recent typical conditions by month, so you can plan a trip around both when chiggers are active and what the weather is doing. The best months to look for chiggers sit around 54 to 83 degrees Fahrenheit, so pack for that.
| Month | Avg high | Avg low | Rain |
|---|---|---|---|
| Jan | 38°F | 23°F | 3" |
| Feb | 40°F | 22°F | 3.1" |
| Mar | 53°F | 34°F | 4.8" |
| Apr | 63°F | 43°F | 4.1" |
| Maybest time | 73°F | 54°F | 4.6" |
| Junbest time | 83°F | 64°F | 3.5" |
| Jul | 85°F | 68°F | 4.3" |
| Aug | 83°F | 66°F | 3.9" |
| Sepbest time | 79°F | 61°F | 3" |
| Oct | 65°F | 48°F | 4.9" |
| Nov | 52°F | 35°F | 1.8" |
| Dec | 45°F | 29°F | 2.3" |
Typical recent conditions (5-year means) from the Open-Meteo archive, averaged for Illinois. Weather varies year to year, so treat these as a guide.
More on chiggers in Illinois:
Sightings of chiggers in Illinois peak in May, when 2 of the year's 7 verified observations are logged — about 28.6% of the annual total. Activity stays high through May, June and September.
The quietest stretch is January, February and March, when chiggers are hardest to find — no verified records exist for January. If a reliable sighting matters, plan around the peak window rather than the off-season.
The chiggers you are most likely to encounter in Illinois are Common Chigger and Hannemania dunni — the most-recorded species in the state. Each keeps its own seasonal rhythm, but the month-by-month pattern above reflects every reported sighting together.
Where to go
Best places to see chiggers in Illinois
- Lewis & Clark National Historic Trail — National Historic Trail
- Lincoln Home National Historic Site — National Historic Site
- Emmett Till and Mamie Till-Mobley National Monument — National Monument
- Mormon Pioneer National Historic Trail — National Historic Trail
- New Philadelphia National Historic Site — National Historic Site
- Pullman National Historical Park — National Historical Park
Frequently asked questions
What is the best month to see chiggers in Illinois?+
May is the single best month, and the broader peak window runs through May, June and September, based on 7 verified iNaturalist observations.
When are chiggers hardest to see in Illinois?+
January is the quietest month for chiggers in Illinois, with no verified records on iNaturalist.
Are chiggers active year-round in Illinois?+
Chiggers are recorded in 4 of 12 months in Illinois, concentrated around May and June.
More places to see chiggers
More wildlife in Illinois