Petersburg · first 14 days — live forecast · rest of month — climate corridor
🗺️ 14-day forecast map
Petersburg & 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
43°
Wed, Sep 9
Coldest night
15°
Mon, Sep 14
Days with precip
2 / 14
of 14 forecast days
Nicest day
Mon, Sep 14
mild, dry, light wind
The next 4 weekends
plan ahead
Sat 5 – Sun 6 Sep
35° 19°
72% precip chance
Sat 12 – Sun 13 Sep
32° 16°
4% precip chance
Sat 19 – Sun 20 Sep
32° 20°
typical range
Sat 26 – Sun 27 Sep
33° 19°
typical range
30 days — Petersburg
14 forecast + 16 climatology
Tue · Today Sunny
37°24°2%⌄
Wind13 mph SW
Gusts35 mph
UV index8 – Very high
Precip chance2%
Sunrise06:27
Sunset19:31
Wed · Tomorrow Sunny
37°25°2%⌄
Wind14 mph SW
Gusts33 mph
UV index8 – Very high
Precip chance2%
Sunrise06:28
Sunset19:29
Thursday 3/9 Sunny
37°26°4%⌄
Wind11 mph SW
Gusts28 mph
UV index9 – Very high
Precip chance4%
Sunrise06:29
Sunset19:28
Friday 4/9 Sunny
37°27°3%⌄
Wind11 mph S
Gusts25 mph
UV index8 – Very high
Precip chance3%
Sunrise06:30
Sunset19:26
Saturday 5/9 Thunderstorms
35°22°7.7 mm⌄
Wind15 mph E
Gusts26 mph
UV index7 – High
Precip chance72%
Sunrise06:31
Sunset19:25
Sunday 6/9 Mostly cloudy
28°19°1.0 mm⌄
Wind12 mph E
Gusts23 mph
UV index7 – High
Precip chance57%
Sunrise06:32
Sunset19:23
Monday 7/9 Mostly cloudy
31°18°16%⌄
Wind11 mph S
Gusts25 mph
UV index7 – High
Precip chance16%
Sunrise06:32
Sunset19:21
Tuesday 8/9 Sunny
40°24°2%⌄
Wind15 mph S
Gusts37 mph
UV index10 – Very high
Precip chance2%
Sunrise06:33
Sunset19:20
Wednesday 9/9 Sunny
43°29°0%⌄
Wind18 mph SW
Gusts40 mph
UV index10 – Very high
Precip chance0%
Sunrise06:34
Sunset19:18
Thursday 10/9 Sunny
33°20°4%⌄
Wind13 mph SW
Gusts38 mph
UV index7 – High
Precip chance4%
Sunrise06:35
Sunset19:17
Friday 11/9 Sunny
30°15°1%⌄
Wind11 mph N
Gusts15 mph
UV index7 – High
Precip chance1%
Sunrise06:36
Sunset19:15
Saturday 12/9 Sunny
31°16°2%⌄
Wind12 mph SE
Gusts28 mph
UV index8 – Very high
Precip chance2%
Sunrise06:37
Sunset19:13
Sunday 13/9 Sunny
32°18°4%⌄
Wind14 mph S
Gusts35 mph
UV index8 – Very high
Precip chance4%
Sunrise06:38
Sunset19:12
Monday 14/9 Mostly cloudy
25°15°8%⌄
Wind15 mph S
Gusts37 mph
UV index6 – High
Precip chance8%
Sunrise06:39
Sunset19:10
Tuesday 15/9 Light rain (climatological)
34°21°1.0 mm⌄
Day≈31–37°
Night≈18–24°
Precip≈0.8 in / September
(climatological)Typical range for these dates · 1991–2020
Wednesday 16/9 Partly cloudy (climatological)
36°23°20%⌄
Day≈33–39°
Night≈20–26°
Precip≈0.8 in / September
(climatological)Typical range for these dates · 1991–2020
Thursday 17/9 Partly cloudy (climatological)
35°22°20%⌄
Day≈32–38°
Night≈19–25°
Precip≈0.8 in / September
(climatological)Typical range for these dates · 1991–2020
Friday 18/9 Light rain (climatological)
36°23°1.9 mm⌄
Day≈33–39°
Night≈20–26°
Precip≈0.8 in / September
(climatological)Typical range for these dates · 1991–2020
Saturday 19/9 Partly cloudy (climatological)
32°20°20%⌄
Day≈29–35°
Night≈17–23°
Precip≈0.8 in / September
(climatological)Typical range for these dates · 1991–2020
Sunday 20/9 Partly cloudy (climatological)
32°20°20%⌄
Day≈29–35°
Night≈17–23°
Precip≈0.8 in / September
(climatological)Typical range for these dates · 1991–2020
Monday 21/9 Rain (climatological)
33°21°2.1 mm⌄
Day≈30–36°
Night≈18–24°
Precip≈0.8 in / September
(climatological)Typical range for these dates · 1991–2020
Tuesday 22/9 Partly cloudy (climatological)
33°21°20%⌄
Day≈30–36°
Night≈18–24°
Precip≈0.8 in / September
(climatological)Typical range for these dates · 1991–2020
Wednesday 23/9 Partly cloudy (climatological)
35°22°20%⌄
Day≈32–38°
Night≈19–25°
Precip≈0.8 in / September
(climatological)Typical range for these dates · 1991–2020
Thursday 24/9 Light rain (climatological)
35°22°1.2 mm⌄
Day≈32–38°
Night≈19–25°
Precip≈0.8 in / September
(climatological)Typical range for these dates · 1991–2020
Friday 25/9 Partly cloudy (climatological)
34°21°20%⌄
Day≈31–37°
Night≈18–24°
Precip≈0.8 in / September
(climatological)Typical range for these dates · 1991–2020
Saturday 26/9 Partly cloudy (climatological)
33°21°20%⌄
Day≈30–36°
Night≈18–24°
Precip≈0.8 in / September
(climatological)Typical range for these dates · 1991–2020
Sunday 27/9 Light rain (climatological)
30°19°1.9 mm⌄
Day≈27–33°
Night≈16–22°
Precip≈0.8 in / September
(climatological)Typical range for these dates · 1991–2020
Monday 28/9 Partly cloudy (climatological)
32°20°20%⌄
Day≈29–35°
Night≈17–23°
Precip≈0.8 in / September
(climatological)Typical range for these dates · 1991–2020
Tuesday 29/9 Partly cloudy (climatological)
35°22°20%⌄
Day≈32–38°
Night≈19–25°
Precip≈0.8 in / September
(climatological)Typical range for these dates · 1991–2020
Wednesday 30/9 Light rain (climatological)
35°22°1.9 mm⌄
Day≈32–38°
Night≈19–25°
Precip≈0.8 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 Petersburg, 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.