Saint Charles · first 14 days — live forecast · rest of month — climate corridor
🗺️ 14-day forecast map
Saint Charles & neighbors — hit play
Every city on the map carries real forecast data from the same models as its city page, refreshed several times a day. The icon is the day's overall look; the number is the afternoon high.
Next 14 days at a glance
from the model forecast
Hottest day
92°
Thu, Sep 3
Coldest night
61°
Tue, Aug 25
Days with precip
6 / 14
of 14 forecast days
Nicest day
Tue, Sep 1
mild, dry, light wind
The next 4 weekends
plan ahead
Sat 29 – Sun 30 Aug
92° 68°
26% precip chance
Sat 5 – Sun 6 Sep
82° 60°
typical range
Sat 12 – Sun 13 Sep
82° 60°
typical range
Sat 19 – Sun 20 Sep
79° 60°
typical range
30 days — Saint Charles
14 forecast + 16 climatology
Sun · Today Sunny
87°65°23.6 mm⌄
Wind10 mph W
Gusts18 mph
UV index8 – High
Precip chance72%
Sunrise06:29
Sunset19:51
Mon · Tomorrow Sunny
86°62°4%⌄
Wind6 mph N
Gusts21 mph
UV index7 – High
Precip chance4%
Sunrise06:30
Sunset19:50
Tuesday 25/8 Mostly cloudy
84°61°7%⌄
Wind8 mph NW
Gusts20 mph
UV index8 – High
Precip chance7%
Sunrise06:30
Sunset19:48
Wednesday 26/8 Mostly cloudy
88°63°9%⌄
Wind9 mph SE
Gusts28 mph
UV index8 – Very high
Precip chance9%
Sunrise06:31
Sunset19:47
Thursday 27/8 Mostly cloudy
86°69°3.9 mm⌄
Wind11 mph S
Gusts27 mph
UV index6 – Moderate
Precip chance73%
Sunrise06:32
Sunset19:45
Friday 28/8 Sunny
90°68°0.5 mm⌄
Wind6 mph S
Gusts19 mph
UV index8 – Very high
Precip chance40%
Sunrise06:33
Sunset19:44
Saturday 29/8 Sunny
92°72°0.3 mm⌄
Wind7 mph SE
Gusts17 mph
UV index8 – Very high
Precip chance17%
Sunrise06:34
Sunset19:42
Sunday 30/8 Mostly cloudy
91°68°26%⌄
Wind9 mph S
Gusts14 mph
UV index7 – High
Precip chance26%
Sunrise06:35
Sunset19:41
Monday 31/8 Sunny
85°68°0.6 mm⌄
Wind7 mph NW
Gusts15 mph
UV index7 – High
Precip chance39%
Sunrise06:36
Sunset19:39
Tuesday 1/9 Mostly cloudy
83°68°10%⌄
Wind6 mph E
Gusts14 mph
UV index7 – High
Precip chance10%
Sunrise06:37
Sunset19:38
Wednesday 2/9 Fog
83°68°3.9 mm⌄
Wind9 mph S
Gusts23 mph
UV index6 – High
Precip chance82%
Sunrise06:38
Sunset19:36
Thursday 3/9 Fog
92°71°4.8 mm⌄
Wind6 mph NW
Gusts26 mph
UV index7 – High
Precip chance83%
Sunrise06:38
Sunset19:35
Friday 4/9 Showers
85°72°7.2 mm⌄
Wind11 mph NW
Gusts19 mph
UV index7 – High
Precip chance83%
Sunrise06:39
Sunset19:33
Saturday 5/9 Showers
82°69°12.1 mm⌄
Wind4 mph NW
Gusts13 mph
UV index6 – High
Precip chance91%
Sunrise06:40
Sunset19:32
Sunday 6/9 Rain (climatological)
78°60°12.4 mm⌄
Day≈73–83°
Night≈55–66°
Precip≈4.9 in / September
(climatological)Typical range for these dates · 1991–2020
Monday 7/9 Partly cloudy (climatological)
85°65°20%⌄
Day≈80–91°
Night≈59–70°
Precip≈4.9 in / September
(climatological)Typical range for these dates · 1991–2020
Tuesday 8/9 Partly cloudy (climatological)
86°65°20%⌄
Day≈80–91°
Night≈60–70°
Precip≈4.9 in / September
(climatological)Typical range for these dates · 1991–2020
Wednesday 9/9 Rain (climatological)
81°62°9.9 mm⌄
Day≈76–87°
Night≈57–68°
Precip≈4.9 in / September
(climatological)Typical range for these dates · 1991–2020
Thursday 10/9 Partly cloudy (climatological)
76°59°20%⌄
Day≈71–82°
Night≈54–65°
Precip≈4.9 in / September
(climatological)Typical range for these dates · 1991–2020
Friday 11/9 Partly cloudy (climatological)
76°59°20%⌄
Day≈71–82°
Night≈54–65°
Precip≈4.9 in / September
(climatological)Typical range for these dates · 1991–2020
Saturday 12/9 Rain (climatological)
78°60°15.7 mm⌄
Day≈73–84°
Night≈55–66°
Precip≈4.9 in / September
(climatological)Typical range for these dates · 1991–2020
Sunday 13/9 Partly cloudy (climatological)
82°63°20%⌄
Day≈77–88°
Night≈58–68°
Precip≈4.9 in / September
(climatological)Typical range for these dates · 1991–2020
Monday 14/9 Partly cloudy (climatological)
83°64°20%⌄
Day≈78–89°
Night≈58–69°
Precip≈4.9 in / September
(climatological)Typical range for these dates · 1991–2020
Tuesday 15/9 Rain (climatological)
87°65°7.4 mm⌄
Day≈81–92°
Night≈60–71°
Precip≈4.9 in / September
(climatological)Typical range for these dates · 1991–2020
Wednesday 16/9 Partly cloudy (climatological)
82°62°20%⌄
Day≈76–87°
Night≈57–68°
Precip≈4.9 in / September
(climatological)Typical range for these dates · 1991–2020
Thursday 17/9 Partly cloudy (climatological)
79°61°20%⌄
Day≈74–84°
Night≈55–66°
Precip≈4.9 in / September
(climatological)Typical range for these dates · 1991–2020
Friday 18/9 Rain (climatological)
76°59°9.5 mm⌄
Day≈71–82°
Night≈54–65°
Precip≈4.9 in / September
(climatological)Typical range for these dates · 1991–2020
Saturday 19/9 Partly cloudy (climatological)
79°61°20%⌄
Day≈73–84°
Night≈55–66°
Precip≈4.9 in / September
(climatological)Typical range for these dates · 1991–2020
Sunday 20/9 Partly cloudy (climatological)
78°60°20%⌄
Day≈72–83°
Night≈55–65°
Precip≈4.9 in / September
(climatological)Typical range for these dates · 1991–2020
Monday 21/9 Rain (climatological)
85°64°11.2 mm⌄
Day≈79–90°
Night≈59–70°
Precip≈4.9 in / September
(climatological)Typical range for these dates · 1991–2020
How does a 30-day outlook work?
The first 14 days are a live model forecast. The back half of the month shows the typical range for those dates — useful for planning, not a literal prediction.
First 14 days: a real forecast, blended from NBM, ECMWF and GFS runs. Trust it most inside three days; by the second week treat it as a lean, not a promise.
Rest of the month: past day 14 we stop pretending to forecast and switch to the climate corridor — the range those dates have produced over three decades computed directly for Saint Charles, with mild week-to-week wiggle.
Good question for this page: "Is late August usually humid in Chicago?" Bad question: "Do I need an umbrella on the 29th?" — three weeks out no one knows, and that's the honest answer.