Saint Johns · first 14 days — live forecast · rest of month — climate corridor
🗺️ 14-day forecast map
Saint Johns & 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
98°
Wed, Sep 2
Coldest night
46°
Wed, Sep 9
Days with precip
6 / 14
of 14 forecast days
Nicest day
Sat, Sep 12
mild, dry, light wind
The next 4 weekends
plan ahead
Sat 5 – Sun 6 Sep
80° 56°
8% precip chance
Sat 12 – Sun 13 Sep
77° 55°
16% precip chance
Sat 19 – Sun 20 Sep
81° 58°
typical range
Sat 26 – Sun 27 Sep
82° 59°
typical range
30 days — Saint Johns
14 forecast + 16 climatology
Wed · Today Mostly cloudy
98°72°0.4 mm⌄
Wind18 mph W
Gusts31 mph
UV index6 – Moderate
Precip chance36%
Sunrise07:03
Sunset20:11
Thu · Tomorrow Showers
90°69°3.3 mm⌄
Wind18 mph W
Gusts27 mph
UV index5 – Moderate
Precip chance76%
Sunrise07:05
Sunset20:10
Friday 4/9 Showers
80°67°20.9 mm⌄
Wind10 mph NE
Gusts18 mph
UV index7 – High
Precip chance90%
Sunrise07:06
Sunset20:08
Saturday 5/9 Sunny
79°63°7%⌄
Wind9 mph E
Gusts22 mph
UV index7 – High
Precip chance7%
Sunrise07:07
Sunset20:06
Sunday 6/9 Sunny
80°56°8%⌄
Wind8 mph E
Gusts15 mph
UV index7 – High
Precip chance8%
Sunrise07:08
Sunset20:04
Monday 7/9 Mostly cloudy
81°62°6.3 mm⌄
Wind14 mph NE
Gusts23 mph
UV index6 – High
Precip chance78%
Sunrise07:09
Sunset20:03
Tuesday 8/9 Showers
60°49°34.1 mm⌄
Wind20 mph NE
Gusts34 mph
UV index4 – Moderate
Precip chance90%
Sunrise07:10
Sunset20:01
Wednesday 9/9 Mostly cloudy
64°46°0.2 mm⌄
Wind11 mph SE
Gusts26 mph
UV index4 – Moderate
Precip chance24%
Sunrise07:11
Sunset19:59
Thursday 10/9 Mostly cloudy
86°58°2.1 mm⌄
Wind15 mph S
Gusts32 mph
UV index7 – High
Precip chance70%
Sunrise07:12
Sunset19:57
Friday 11/9 Mostly cloudy
80°63°0.1 mm⌄
Wind15 mph W
Gusts31 mph
UV index5 – Moderate
Precip chance24%
Sunrise07:13
Sunset19:56
Saturday 12/9 Mostly cloudy
70°58°15%⌄
Wind10 mph NE
Gusts20 mph
UV index6 – High
Precip chance15%
Sunrise07:14
Sunset19:54
Sunday 13/9 Mostly cloudy
77°55°16%⌄
Wind9 mph S
Gusts23 mph
UV index7 – High
Precip chance16%
Sunrise07:15
Sunset19:52
Monday 14/9 Showers
76°64°1.0 mm⌄
Wind12 mph N
Gusts33 mph
UV index5 – Moderate
Precip chance66%
Sunrise07:16
Sunset19:50
Tuesday 15/9 Mostly cloudy
63°54°23%⌄
Wind8 mph NE
Gusts18 mph
UV index4 – Moderate
Precip chance23%
Sunrise07:18
Sunset19:48
Wednesday 16/9 Rain (climatological)
79°61°7.9 mm⌄
Day≈73–84°
Night≈55–66°
Precip≈5.9 in / September
(climatological)Typical range for these dates · 1991–2020
Thursday 17/9 Partly cloudy (climatological)
80°61°20%⌄
Day≈75–85°
Night≈56–67°
Precip≈5.9 in / September
(climatological)Typical range for these dates · 1991–2020
Friday 18/9 Partly cloudy (climatological)
80°62°20%⌄
Day≈75–86°
Night≈56–67°
Precip≈5.9 in / September
(climatological)Typical range for these dates · 1991–2020
Saturday 19/9 Rain (climatological)
81°62°19.9 mm⌄
Day≈76–87°
Night≈57–67°
Precip≈5.9 in / September
(climatological)Typical range for these dates · 1991–2020
Sunday 20/9 Partly cloudy (climatological)
75°58°20%⌄
Day≈70–81°
Night≈53–64°
Precip≈5.9 in / September
(climatological)Typical range for these dates · 1991–2020
Monday 21/9 Partly cloudy (climatological)
71°56°20%⌄
Day≈66–77°
Night≈51–61°
Precip≈5.9 in / September
(climatological)Typical range for these dates · 1991–2020
Tuesday 22/9 Rain (climatological)
76°59°14.4 mm⌄
Day≈71–81°
Night≈53–64°
Precip≈5.9 in / September
(climatological)Typical range for these dates · 1991–2020
Wednesday 23/9 Partly cloudy (climatological)
76°59°20%⌄
Day≈71–81°
Night≈53–64°
Precip≈5.9 in / September
(climatological)Typical range for these dates · 1991–2020
Thursday 24/9 Partly cloudy (climatological)
82°62°20%⌄
Day≈76–87°
Night≈57–68°
Precip≈5.9 in / September
(climatological)Typical range for these dates · 1991–2020
Friday 25/9 Rain (climatological)
83°63°17.4 mm⌄
Day≈77–88°
Night≈58–68°
Precip≈5.9 in / September
(climatological)Typical range for these dates · 1991–2020
Saturday 26/9 Partly cloudy (climatological)
82°62°20%⌄
Day≈76–87°
Night≈57–68°
Precip≈5.9 in / September
(climatological)Typical range for these dates · 1991–2020
Sunday 27/9 Partly cloudy (climatological)
76°59°20%⌄
Day≈70–81°
Night≈53–64°
Precip≈5.9 in / September
(climatological)Typical range for these dates · 1991–2020
Monday 28/9 Rain (climatological)
71°56°14.9 mm⌄
Day≈66–77°
Night≈51–61°
Precip≈5.9 in / September
(climatological)Typical range for these dates · 1991–2020
Tuesday 29/9 Partly cloudy (climatological)
75°58°20%⌄
Day≈70–81°
Night≈53–64°
Precip≈5.9 in / September
(climatological)Typical range for these dates · 1991–2020
Wednesday 30/9 Partly cloudy (climatological)
80°61°20%⌄
Day≈75–85°
Night≈56–67°
Precip≈5.9 in / September
(climatological)Typical range for these dates · 1991–2020
Thursday 1/10 Rain (climatological)
67°49°14.4 mm⌄
Day≈61–72°
Night≈43–54°
Precip≈5.9 in / October
(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 Johns, 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.