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AlgonquinReport this photo · linked, not stored
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Climate guideThirty-year normals for Algonquin, Illinois
Algonquin climate by month
Hot-summer humid continental · DfaBest May · Sep–Oct
Annual mean49°day and night
Seasonal swing51°warmest vs coolest
Precipitation36.8 in117 wet days a year
42.17° N, 88.29° WElevation 741 ftUTC−5 · Central Daylight Time
When to goAlgonquin · weather score
Best timeMay · Sep–Oct
October: high / low62° / 41°
iSummary
What the weather is like
Algonquin has a hot-summer humid continental climate (Köppen Dfa): warm summers, cold winters and precipitation in every season.
The warmest month is July, when afternoons average 84° and nights 62°. January is the coolest month, with highs of 30° and lows of 13°. The difference between the warmest and the coolest month is about 51°, a large swing typical of continental interiors.
About 36.8 in of precipitation falls in an average year. May is the wettest month (4.2 in, 13 wet days) and January the driest (1.6 in, 7 wet days). Cloud cover ranges from 30% in July to 48% in December.
Compared with Washington, the capital, Algonquin is 2.9° cooler on a July afternoon and receives less precipitation over the year.
Year in figures
- Hottest afternoons
- 84° · July
- Coldest nights
- 13° · January
- Wettest month
- May
- Driest month
- January
- Clearest skies
- July · 30% cloud
- Longest day
- 15 h 14 min
- Shortest day
- 9 h 07 min
iiCharts
Twelve months at a glance
Temperature and precipitation
Daily high/low range bars, monthly precipitation columnsTemperature curve
Average high, lowDaylight
Hours between sunrise and sunset on the 15th of each monthiiiData table
Climate normals month by month
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Average high | 30° | 35° | 46° | 59° | 71° | 80° | 84° | 82° | 75° | 62° | 47° | 35° |
| Average low | 13° | 17° | 27° | 37° | 48° | 58° | 62° | 60° | 52° | 41° | 30° | 19° |
| Precipitation | 1.6 in | 1.6 in | 2.2 in | 3.5 in | 4.2 in | 4.1 in | 3.9 in | 4.6 in | 3.3 in | 3.0 in | 2.8 in | 2.0 in |
| Wet days (≥1 mm) | 7 | 7 | 8.6 | 10.9 | 13.4 | 13.4 | 11.8 | 11.8 | 9.2 | 9.3 | 7.3 | 7.7 |
| Cloud cover | 47% | 47% | 44% | 43% | 40% | 35% | 30% | 31% | 31% | 38% | 46% | 48% |
| Daylight | 9h 27 | 10h 36 | 11h 54 | 13h 21 | 14h 34 | 15h 14 | 14h 58 | 13h 54 | 12h 31 | 11h 07 | 9h 49 | 9h 07 |
| Month score | 34 | 34 | 32 | 54 | 64 | 59 | 56 | 60 | 78 | 68 | 34 | 32 |
ivMonth by month
Algonquin in every month
January34
30° / 13°
1.6 in · 7 wet days
February34
35° / 17°
1.6 in · 7 wet days
March32
46° / 27°
2.2 in · 8.6 wet days
April54
59° / 37°
3.5 in · 10.9 wet days
May64
71° / 48°
4.2 in · 13.4 wet days
June59
80° / 58°
4.1 in · 13.4 wet days
July56
84° / 62°
3.9 in · 11.8 wet days
August60
82° / 60°
4.6 in · 11.8 wet days
September78
75° / 52°
3.3 in · 9.2 wet days
October68
62° / 41°
3.0 in · 9.3 wet days
November34
47° / 30°
2.8 in · 7.3 wet days
December32
35° / 19°
2.0 in · 7.7 wet days