Illinois 天気 予報
Illinois weather: 12°C, 晴れ. 時間別 forecast, 14-day outlook, UV, air quality and the best timeからvisit.
Illinois weather in 10月
One of the best monthsからvisit Illinois.
10月 runs 2°C warmer than the annual average in Illinois.
天気 map for Illinois
Animated model layers. Pick a layerからload it.
Animated layers by 風y. For pin-level detail and nearby places, see the interactive map below.
気候 in Illinois month by month
Average high, average low and total rainfall, based on three years of reanalysis data.
| 月 | Avg high | Avg low | 雨fall | Rating |
|---|---|---|---|---|
| 1月 | 1° | -7° | 62 mm | ★★☆☆☆ |
| 2月 | 8° | -3° | 20 mm | ★★★☆☆ |
| 3月 | 15° | 4° | 90 mm | ★★★☆☆ |
| 4月 | 19° | 9° | 135 mm | ★★★☆☆ |
| 5月 | 24° | 13° | 100 mm | ★★★★☆ |
| 6月 | 28° | 19° | 117 mm | ★★★★☆ |
| 7月 | 30° | 21° | 129 mm | ★★★★☆ |
| 8月 | 29° | 19° | 75 mm | ★★★★☆ |
| 9月 | 27° | 17° | 35 mm | ★★★★☆ |
| 10月 | 21° | 10° | 25 mm | ★★★★☆ |
| 11月 | 12° | 3° | 79 mm | ★★★☆☆ |
| 12月 | 6° | -2° | 62 mm | ★★☆☆☆ |
気候 type: 大陸al. 出典： Open-Meteo archive (ERA5).
訪問に最適な時期 Illinois
Go in 8月, 9月 and 10月. These months score highest on comfortable temperatures, low rainfall and useful daylight.
Hardest months: 1月, 2月 and 12月 - expect the least comfortable mix of heat, cold or rain.
Whatからpack, whatからskip
- 日glasses, a brimmed hat and SPF 30+
- A packable rain shell - 2 of the next 7 days carry a real chance of rain
- If your dates are flexible, avoid 1月, 2月 and 12月 - historically the least comfortable months here.
How Illinois compares、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 | 1163 mm |
| St. Louis | 137 km | 15°C | +1°C warmer | 1163 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 |
時間帯別のIllinois 予報を見る
Illinois weather - more answers
Explore Illinois
Every topic we hold for this place, and the same topic for the places around it.
天気 for related places
Frequently asked questions
Where is Illinois?
Illinois is a state in アメリカ合衆国. Its coordinates are 39.7817, -89.6501. It lies in 北アメリカ.
What is the weather like in Illinois現在?
It is currently 12°C (54°F)、晴れ. 湿度 is 74% and wind is 8 km/h.
When is the best timeからvisit Illinois?
8月, 9月 and 10月 offer the most comfortable conditions in Illinois, which has a continental climate. 1月, 2月 and 12月 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 6:15 PM.
How many people live in Illinois?
Illinois has a population of approximately 12.6 million.
What is the nearest airportから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から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. |
|---|---|
| 予報 and observations | Open-Meteo (ECMWF and national models). |
| 大気質 and pollen | Copernicus CAMS via Open-Meteo. US AQI scale. |
| 気候 averages | ERA5 reanalysis via the Open-Meteo archive, aggregated over 3 years. |
| Official alerts | US National 天気 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 10月 28, 2026 at 6:15 PM local time. Live blocks refresh every 15 minutes; climate averages monthly.
