Live Weather & Forecast

Weather in Petersburg

Q: What is the current weather in Petersburg?

Current conditions in Petersburg: Overcast, temperature 20°C, humidity 78%.

Q: What is the best time to visit Petersburg?

The best time to visit Petersburg is typically June – September. Warm, dry summers — ideal for outdoor activities.

Q: What are the GPS coordinates used for the weather forecast in Petersburg?

The weather forecast for Petersburg uses coordinates 40.0117, -89.8482.

Illinois, United States · Real-time conditions & 3-day outlook

20^°C

Feels like 20°C

68°F / Feels 68°F

Overcast

Petersburg, Illinois

🌞 Daytime

Updated: 2026-04-15 09:30

💧

Humidity

78%

💨

Wind

23.8 km/h SSW

🌬️

Wind Gust

34.9 km/h

🌡️

Pressure

1011 mb

👁️

Visibility

16 km

☀️

UV Index

0.8 (Low)

🌧️

Precipitation

0 mm

☁️

Cloud Cover

100%

💦

Dew Point

16.3°C

🌐

Wind Degree

205°

Air Quality Index

US EPA: Good UK DEFRA: Low (1)

141.9 μg/m³

NO₂

2.4 μg/m³

O₃

80 μg/m³

SO₂

1.3 μg/m³

PM 2.5

6.8 μg/m³

PM 10

7.3 μg/m³

Weather Alerts 2

Met · Severe · Immediate

Flood Warning issued April 14 at 8:55PM CDT by NWS Lincoln IL

...The Flood Warning is extended for the following rivers in Illinois... Illinois River at Beardstown affecting Schuyler, Cass, Morgan and Brown Counties. ...The Flood Warning continues for the following rivers in Illinois... Illinois River near Havana affecting Fulton, Cass and Mason Counties. .The following forecasts are based on observed precipitation, soil moisture conditions, and forecast...

Persons with interests along this river need to remain aware of the latest forecasts and associated flood risk for their area. Stay tuned for further updates on this flooding situation. Caution is urged when walking near riverbanks. Additional information is available at www.weather.gov.

Effective: 2026-04-14T20:55:00-05:00 · Expires: 2026-04-15T13:00:00-05:00

Met · Severe · Immediate

Flood Warning issued April 14 at 8:55PM CDT by NWS Lincoln IL

Effective: 2026-04-14T20:55:00-05:00 · Expires: 2026-04-15T13:00:00-05:00

Today's Hourly Forecast

24-hour breakdown for Petersburg, Illinois

12 AM

24°

Clear

💧 64% 💨 32.8 km/h

1 AM

24°

Clear

💧 68% 💨 44.3 km/h

2 AM

23°

Clear

💧 70% 💨 23.4 km/h

3 AM

23°

Clear

💧 71% 💨 22.7 km/h

4 AM

23°

Clear

💧 71% 💨 22 km/h

5 AM

23°

Clear

💧 71% 💨 26.3 km/h

6 AM

22°

Patchy rain nearby

💧 74% 💨 26.6 km/h 🌧️ 60%

7 AM

22°

Patchy light drizzle

💧 78% 💨 18.7 km/h 🌧️ 100%

8 AM

23°

Patchy rain nearby

💧 75% 💨 21.6 km/h 🌧️ 74%

9 AM

20°

Overcast

💧 78% 💨 23.8 km/h

10 AM

23°

Overcast

💧 53% 💨 23 km/h

11 AM

22°

Light rain

💧 86% 💨 25.6 km/h 🌧️ 100%

12 PM

23°

Light rain

💧 83% 💨 25.9 km/h 🌧️ 100%

1 PM

25°

Patchy rain nearby

💧 78% 💨 24.8 km/h 🌧️ 87%

2 PM

27°

Sunny

💧 72% 💨 24.5 km/h

3 PM

28°

Sunny

💧 64% 💨 21.6 km/h

4 PM

27°

Sunny

💧 57% 💨 22.7 km/h

5 PM

26°

Patchy rain nearby

💧 61% 💨 23 km/h 🌧️ 100%

6 PM

23°

Thundery outbreaks in nearby

💧 70% 💨 25.9 km/h

7 PM

23°

Overcast

💧 80% 💨 20.9 km/h

8 PM

23°

Thundery outbreaks in nearby

💧 78% 💨 25.9 km/h

9 PM

21°

Clear

💧 83% 💨 28.8 km/h

10 PM

21°

Overcast

💧 91% 💨 26.6 km/h

11 PM

20°

Partly Cloudy

💧 88% 💨 23.8 km/h

3-Day Forecast

Daily overview for Petersburg, Illinois

Today

Patchy rain nearby

29° / 19°

🌧️ 87% chance of rain

💧 Avg. humidity: 73%

💨 Max wind: 44.3 km/h

🌧️ Total precip: 3.44 mm

☀️ UV Index: 1

🌅 Sunrise: 06:21 AM

🌇 Sunset: 07:38 PM

🌙 Waning Crescent

🌑 Moon: 8% lit

Thu, Apr 16

Moderate rain

26° / 13°

🌧️ 87% chance of rain

💧 Avg. humidity: 69%

💨 Max wind: 30.6 km/h

🌧️ Total precip: 8.37 mm

☀️ UV Index: 1.8

🌅 Sunrise: 06:20 AM

🌇 Sunset: 07:39 PM

🌙 Waning Crescent

🌑 Moon: 3% lit

Fri, Apr 17

Cloudy

28° / 15°

🌧️ 0% chance of rain

💧 Avg. humidity: 78%

💨 Max wind: 37.8 km/h

🌧️ Total precip: 0 mm

☀️ UV Index: 1.9

🌅 Sunrise: 06:18 AM

🌇 Sunset: 07:40 PM

🌙 New Moon

🌑 Moon: 0% lit

Best Time to Visit Petersburg

Plan your trip to Petersburg, United States around the most favorable weather conditions.

Peak Season

June – September

Warm, dry summers — ideal for outdoor activities.

Shoulder Season

April – May, October

Fewer crowds, moderate prices, mild weather.

Off Season

November – March

Cooler temperatures; some regions may experience rain or snow.

← Back to Petersburg 🗓 View Holidays 2026

Frequently Asked Questions

What is the current weather in Petersburg?

Current conditions in Petersburg: Overcast, temperature 20°C, humidity 78%.

What is the best time to visit Petersburg?

The best time to visit Petersburg is typically June – September. Warm, dry summers — ideal for outdoor activities.

What is the climate like in Petersburg?

Petersburg is located at approximately 40° latitude. It has a temperate climate with warm summers and cold winters.

Does it rain a lot in Petersburg?

The wettest period in Petersburg is typically during November – March. Cooler temperatures; some regions may experience rain or snow.

What should I pack for a trip to Petersburg?

For visits to Petersburg during June – September: light clothing and sun protection. For November – March: layers and a waterproof jacket are recommended.

What country is Petersburg in?

Petersburg is located in United States, in the state of Illinois.

What are the public holidays in Petersburg in 2026?

View the 2026 public holidays for Petersburg on our Holidays page.

What are the GPS coordinates used for the weather forecast in Petersburg?

The weather forecast for Petersburg uses coordinates 40.0117, -89.8482.