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
104°
Fri, Sep 4
Coldest night
55°
Tue, Sep 15
Days with precip
5 / 14
of 14 forecast days
Nicest day
Tue, Sep 15
mild, dry, light wind
The next 4 weekends
plan ahead
Sat 5 – Sun 6 Sep
95° 67°
73% precip chance
Sat 12 – Sun 13 Sep
76° 60°
90% precip chance
Sat 19 – Sun 20 Sep
90° 67°
typical range
Sat 26 – Sun 27 Sep
90° 66°
typical range
30 days — Petersburg
14 forecast + 16 climatology
Fri · Today Sunny
104°73°1.5 mm⌄
Wind16 mph NW
Gusts24 mph
UV index9 – Very high
Precip chance57%
Sunrise06:42
Sunset19:34
Sat · Tomorrow Mostly cloudy
95°73°1.4 mm⌄
Wind8 mph E
Gusts18 mph
UV index8 – High
Precip chance57%
Sunrise06:43
Sunset19:33
Sunday 6/9 Sunny
85°67°9.7 mm⌄
Wind10 mph E
Gusts23 mph
UV index7 – High
Precip chance73%
Sunrise06:44
Sunset19:31
Monday 7/9 Sunny
84°63°0.5 mm⌄
Wind8 mph E
Gusts20 mph
UV index7 – High
Precip chance36%
Sunrise06:45
Sunset19:30
Tuesday 8/9 Mostly cloudy
84°60°8%⌄
Wind9 mph SE
Gusts24 mph
UV index7 – High
Precip chance8%
Sunrise06:46
Sunset19:28
Wednesday 9/9 Mostly cloudy
90°61°10%⌄
Wind9 mph SW
Gusts31 mph
UV index7 – High
Precip chance10%
Sunrise06:46
Sunset19:27
Thursday 10/9 Sunny
95°71°0.8 mm⌄
Wind11 mph W
Gusts34 mph
UV index8 – Very high
Precip chance36%
Sunrise06:47
Sunset19:25
Friday 11/9 Mostly cloudy
79°61°11%⌄
Wind9 mph N
Gusts23 mph
UV index6 – High
Precip chance11%
Sunrise06:48
Sunset19:23
Saturday 12/9 Showers
66°60°48.0 mm⌄
Wind8 mph NE
Gusts23 mph
UV index4 – Moderate
Precip chance90%
Sunrise06:49
Sunset19:22
Sunday 13/9 Fog
76°64°9.1 mm⌄
Wind7 mph NW
Gusts19 mph
UV index6 – High
Precip chance89%
Sunrise06:50
Sunset19:20
Monday 14/9 Mostly cloudy
85°66°19%⌄
Wind11 mph N
Gusts24 mph
UV index7 – High
Precip chance19%
Sunrise06:50
Sunset19:19
Tuesday 15/9 Sunny
73°55°2%⌄
Wind11 mph N
Gusts24 mph
UV index6 – High
Precip chance2%
Sunrise06:51
Sunset19:17
Wednesday 16/9 Thunderstorms
92°55°12%⌄
Wind7 mph E
Gusts18 mph
UV index7 – High
Precip chance12%
Sunrise06:52
Sunset19:16
Thursday 17/9 Fog
91°72°19%⌄
Wind7 mph SE
Gusts17 mph
UV index8 – Very high
Precip chance19%
Sunrise06:53
Sunset19:14
Friday 18/9 Rain (climatological)
86°64°8.2 mm⌄
Day≈80–91°
Night≈59–70°
Precip≈6.1 in / September
(climatological)Typical range for these dates · 1991–2020
Saturday 19/9 Partly cloudy (climatological)
90°67°20%⌄
Day≈85–96°
Night≈62–73°
Precip≈6.1 in / September
(climatological)Typical range for these dates · 1991–2020
Sunday 20/9 Partly cloudy (climatological)
89°67°20%⌄
Day≈84–95°
Night≈61–72°
Precip≈6.1 in / September
(climatological)Typical range for these dates · 1991–2020
Monday 21/9 Rain (climatological)
86°65°20.5 mm⌄
Day≈81–92°
Night≈59–70°
Precip≈6.1 in / September
(climatological)Typical range for these dates · 1991–2020
Tuesday 22/9 Partly cloudy (climatological)
85°64°20%⌄
Day≈80–91°
Night≈59–69°
Precip≈6.1 in / September
(climatological)Typical range for these dates · 1991–2020
Wednesday 23/9 Partly cloudy (climatological)
81°61°20%⌄
Day≈75–86°
Night≈56–67°
Precip≈6.1 in / September
(climatological)Typical range for these dates · 1991–2020
Thursday 24/9 Rain (climatological)
83°63°8.7 mm⌄
Day≈78–89°
Night≈58–68°
Precip≈6.1 in / September
(climatological)Typical range for these dates · 1991–2020
Friday 25/9 Partly cloudy (climatological)
86°65°20%⌄
Day≈81–92°
Night≈59–70°
Precip≈6.1 in / September
(climatological)Typical range for these dates · 1991–2020
Saturday 26/9 Partly cloudy (climatological)
90°67°20%⌄
Day≈85–96°
Night≈62–72°
Precip≈6.1 in / September
(climatological)Typical range for these dates · 1991–2020
Sunday 27/9 Rain (climatological)
88°66°10.3 mm⌄
Day≈83–94°
Night≈61–71°
Precip≈6.1 in / September
(climatological)Typical range for these dates · 1991–2020
Monday 28/9 Partly cloudy (climatological)
88°66°20%⌄
Day≈83–94°
Night≈61–71°
Precip≈6.1 in / September
(climatological)Typical range for these dates · 1991–2020
Tuesday 29/9 Partly cloudy (climatological)
85°64°20%⌄
Day≈80–90°
Night≈58–69°
Precip≈6.1 in / September
(climatological)Typical range for these dates · 1991–2020
Wednesday 30/9 Rain (climatological)
81°61°16.4 mm⌄
Day≈75–86°
Night≈56–67°
Precip≈6.1 in / September
(climatological)Typical range for these dates · 1991–2020
Thursday 1/10 Partly cloudy (climatological)
72°53°20%⌄
Day≈67–77°
Night≈48–58°
Precip≈6.1 in / October
(climatological)Typical range for these dates · 1991–2020
Friday 2/10 Partly cloudy (climatological)
75°55°20%⌄
Day≈70–81°
Night≈49–60°
Precip≈6.1 in / October
(climatological)Typical range for these dates · 1991–2020
Saturday 3/10 Rain (climatological)
80°58°10.3 mm⌄
Day≈75–86°
Night≈53–63°
Precip≈6.1 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 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.