Illinois Κλίμα and Average Καιρός
Κλίμα of Illinois: average temperatures, rainfall and seasons month by month.
Κλίμα in Illinois month by month
Average high, average low and total rainfall, based on three years of reanalysis data.
| Μήνας | Avg high | Avg low | Βροχήfall | Rating |
|---|---|---|---|---|
| Ιανουάριος | 1° | -7° | 62 mm | ★★☆☆☆ |
| Φεβρουάριος | 8° | -3° | 20 mm | ★★★☆☆ |
| Μάρτιος | 15° | 4° | 90 mm | ★★★☆☆ |
| Απρίλιος | 19° | 9° | 135 mm | ★★★☆☆ |
| Μάι | 24° | 13° | 100 mm | ★★★★☆ |
| Ιούνιος | 28° | 19° | 117 mm | ★★★★☆ |
| Ιούλιος | 29° | 21° | 129 mm | ★★★★☆ |
| Αύγουστος | 29° | 19° | 75 mm | ★★★★☆ |
| Σεπτέμβριος | 28° | 17° | 33 mm | ★★★★★ |
| Οκτώβριος | 20° | 10° | 37 mm | ★★★★☆ |
| Νοέμβριος | 12° | 4° | 79 mm | ★★★☆☆ |
| Δεκέμβριος | 6° | -2° | 62 mm | ★★☆☆☆ |
Κλίμα type: Ήπειροςal. Πηγή: Open-Meteo archive (ERA5).
Recent extremes in Illinois
Υψηλόest and lowest readings observed in the last 3 years of reanalysis data - not all-time records.
How Illinois compares με nearby places
Annual averages, and the difference against Illinois.
| Place | Distance | Avg temp | vs here | Annual rain |
|---|---|---|---|---|
| Gateway Arch National Park | 137 km | 15°C | +1°C warmer | 1156 mm |
| St. Louis | 137 km | 15°C | +1°C warmer | 1156 mm |
| Missouri | 255 km | 15°C | +1°C warmer | 1006 mm |
| Indianapolis | 298 km | 13°C | 1°C cooler | 1135 mm |
| Indiana | 298 km | 13°C | 1°C cooler | 1135 mm |
Κλίμα by city in Illinois
1 cities mapped in this atlas
Κλίμα by state park in Illinois
1 state and provincial parks mapped in this atlas
Κλίμα by county in Illinois
1 counties mapped in this atlas
Κλίμα by lake in Illinois
1 lakes mapped in this atlas
Καλύτερη εποχή για επίσκεψη Illinois
Go in Αύγουστος, Σεπτέμβριος and Οκτώβριος. These months score highest on comfortable temperatures, low rainfall and useful daylight.
Hardest months: Ιανουάριος, Φεβρουάριος and Δεκέμβριος - expect the least comfortable mix of heat, cold or rain.
What this means for Illinois
Today is slightly warmer than average for Οκτώβριος. The forecast high of 24°C is 3.6°C above the 20°C typical for this month.
Βροχή is very unlikely today - plans do not need a backup.
No weather-related travel disruption is expected today. Roads and airports should run normally.
Northern Hemisphere, so peak summer falls in Ιούνιος έως Αύγουστος.
The gap between the warmest and coldest month averages 29°C.
What έως pack, what έως skip
- Κυρglasses, a brimmed hat and SPF 30+
- Layers - the daily swing is 19°C, so mornings feel nothing like afternoons
- If your dates are flexible, avoid Ιανουάριος, Φεβρουάριος and Δεκέμβριος - historically the least comfortable months here.
Περίληψη
Illinois is a state in Ηνωμένες Πολιτείες. Illinois is a US state με πρωτεύουσα Springfield. Ο πληθυσμός είναι περίπου 12.6 million. Η πρωτεύουσα είναι Springfield.
Αυτή τη στιγμή είναι 18°C (64°F) in Illinois με Αίθριος. Η αισθητή θερμοκρασία είναι 15°C. Σήμερα η θερμοκρασία κυμαίνεται από 7°C έως 24°C. Η πιθανότητα βροχής είναι 0%. Sightseeing conditions score 9.7/10 - Εξαιρετικές συνθήκες — φύγετε τώρα.
Η καλύτερη εποχή για επίσκεψη στο Illinois is Αύγουστος, Σεπτέμβριος and Οκτώβριος. Το κλίμα είναι continental. Ιανουάριος, Φεβρουάριος and Δεκέμβριος tend έως be the least comfortable months. Ιούλιος is the warmest month με average highs near 29°C, while Ιανουάριος is the coldest με lows near -7°C.
The closest major airport is O'Hare International Airport (ORD), about 284 km away. Nearby highlights include Starved Rock State Park, Lake Michigan, Gateway Arch National Park and Indiana Dunes National Park.
Με απλά λόγια. Today is slightly warmer than average for Οκτώβριος. The forecast high of 24°C is 3.6°C above the 20°C typical for this month. The best window έως be outside is roughly 11 AM έως 2 PM, when temperature, rain chance and wind line up best. stargazing is the strongest bet in Illinois today at 10/10. No weather-related travel disruption is expected today. Roads and airports should run normally.
Compiled from this page's own data: atlas facts plus live Open-Meteo readings.
Quick facts about Illinois
| Τύπος | State |
|---|---|
| Χώρα | Ηνωμένες Πολιτείες |
| Ήπειρος | Βόρεια Αμερική |
| Συντεταγμένες | 39°46′54.1″N 89°39′0.4″W (39.7817, -89.6501) |
| Capital | Springfield |
| Πληθυσμός | 12.600.000 |
| Area | 149.995 km² |
| Abbreviation | IL |
| Ζώνη ώρας | America/Chicago |
| Τοπική ώρα | 12:06 AM (UTC-05:00) |
| Best months | Αύγουστος, Σεπτέμβριος and Οκτώβριος |
| Κλίμα | Ήπειροςal |
Καιρός map for Illinois
Animated model layers. Pick a layer έως load it.
Animated layers by Άνεμοςy. For pin-level detail and nearby places, see the interactive map below.
Explore Illinois
Every topic we hold for this place, and the same topic for the places around it.
Κλίμα for related places
Frequently asked questions
Where is Illinois?
Illinois is a state in Ηνωμένες Πολιτείες. Its coordinates are 39.7817, -89.6501. It lies in Βόρεια Αμερική.
What is the weather like in Illinois τώρα?
It is currently 18°C (64°F) με Αίθριος. Υγρασία is 39% and wind is 8 km/h.
When is the best time έως visit Illinois?
Αύγουστος, Σεπτέμβριος and Οκτώβριος offer the most comfortable conditions in Illinois, which has a continental climate. Ιανουάριος, Φεβρουάριος and Δεκέμβριος are usually the hardest months for outdoor plans.
What time zone is Illinois in?
Illinois observes America/Chicago (UTC-05:00). The local time is 12:06 AM.
How many people live in Illinois?
Illinois has a population of approximately 12.6 million.
What is the nearest airport έως Illinois?
The closest airports are O'Hare International Airport (ORD), 284 km away and Nashville International Airport (BNA), 483 km away.
What are the top things έως do in Illinois?
Popular options include Starved Rock State Park, Lake Michigan, Gateway Arch National Park and Indiana Dunes National Park.
What places are in Illinois?
Illinois covers 4 places in this atlas, including Chicago, Starved Rock State Park, Cook County and Lake Michigan.
Related articles
Data sources and methodology
| Place data | USPOTUS Atlas dataset (us-states) - coordinates, hierarchy and facts. |
|---|---|
| Πρόγνωση and observations | Open-Meteo (ECMWF and national models). |
| Ποιότητα αέρα and pollen | Copernicus CAMS via Open-Meteo. US AQI scale. |
| Κλίμα averages | ERA5 reanalysis via the Open-Meteo archive, aggregated over 3 years. |
| Official alerts | US National Καιρός Service. |
| Method | Scores, comparisons and advice on this page are computed from the inputs above. Distances are straight-line. Nothing is estimated where data is missing - the block is simply not shown. |
Last updated Οκτώβριος 24, 2026 at 12:06 AM local time. Live blocks refresh every 15 minutes; climate averages monthly.
