Williamson County, Illinois, United States

Last updated: 2:09 PM CDT · Refresh

13°C

Feels like 8°

Mostly Cloudy

▲ 13° / ▼ 1°

Wind

11 mph N

Humidity

57%

Dew Point

5°

Pressure

29.65 inHg

Visibility

9 mi

UV Index

4.7

Cloud Cover

62%

Sunrise

6:25 AM

Sunset

4:51 PM

Drag to pan · double-click to forecast a point

WeatherAI™ Analysis

WeatherAI Analysis: Williamson County is currently mostly cloudy at 13°C. Dry conditions are expected through the next 24 hours. Sunrise: 6:25AM · Sunset: 4:51PM.

29 AQI · Good Dominant: O3 Air Quality

Hourly Forecast · Next 24 Hours

Now

13°

3 PM

13°

4 PM

13°

5 PM

12°

6 PM

11°

7 PM

11°

8 PM

8°

9 PM

7°

10 PM

6°

11 PM

5°

12 AM

4°

1 AM

3°

2 AM

3°

3 AM

2°

4 AM

2°

5 AM

2°

6 AM

1°

7 AM

2°

8 AM

3°

9 AM

6°

10 AM

7°

11 AM

8°

12 PM

11°

1 PM

11°

7-Day Forecast

Today

13° 1°

Mostly Cloudy.

Sat

14° 1°

Mostly Clear.

Sun

18° 4°

Clear.

Mon

19° 7°

Clear.

Tue

20° 9°

Clear with a 28% chance of rain.

Wed

18° 7°

Mostly Clear with a 41% chance of rain.

Thu

13° 4°

Mostly Cloudy with a 43% chance of rain.

+ Feels like

TimeTempConditionsPrecipWindHumidity

Now 13° Mostly Cloudy 0% 11 mph N 57%

3 PM 13° Partly Cloudy 0% 11 mph NNW 56%

4 PM 13° Partly Cloudy 0% 10 mph NNW 56%

5 PM 12° Partly Cloudy 0% 8 mph NNW 60%

6 PM 11° Partly Cloudy 0% 7 mph N 66%

7 PM 11° Partly Cloudy 0% 6 mph N 68%

8 PM 8° Mostly Clear 0% 6 mph N 68%

9 PM 7° Mostly Clear 0% 5 mph NNW 70%

10 PM 6° Clear 0% 4 mph NNW 74%

11 PM 5° Clear 0% 4 mph NNW 77%

12 AM 4° Clear 0% 4 mph NNW 81%

1 AM 3° Clear 0% 3 mph NNW 84%

2 AM 3° Clear 0% 3 mph NNW 87%

3 AM 2° Clear 0% 3 mph NNW 89%

4 AM 2° Clear 0% 2 mph NNW 90%

5 AM 2° Clear 0% 2 mph NW 91%

6 AM 1° Clear 0% 2 mph NW 91%

7 AM 2° Clear 0% 3 mph NW 90%

8 AM 3° Clear 0% 3 mph NNW 83%

9 AM 6° Clear 0% 4 mph NNW 72%

10 AM 7° Mostly Clear 0% 4 mph NNW 63%

11 AM 8° Mostly Clear 0% 4 mph NNW 58%

12 PM 11° Mostly Clear 0% 5 mph NNW 55%

1 PM 11° Mostly Clear 0% 5 mph NNW 53%

15-Day Forecast

Today

11/6

Mostly Cloudy

1°

13°

Sat

11/7

Mostly Clear

1°

14°

Sun

11/8

Clear

4°

18°

Mon

11/9

Clear

7°

19°

Tue

11/10

Clear

28%

9°

20°

Wed

11/11

Mostly Clear

41%

7°

18°

Thu

11/12

Mostly Cloudy

43%

4°

13°

Fri

11/13

Mostly Cloudy

30%

0°

9°

Sat

11/14

Mostly Clear

22%

-2°

10°

Sun

11/15

Partly Cloudy

49%

-2°

13°

Mon

11/16

Overcast

73%

2°

16°

Tue

11/17

Drizzle

80%

8°

15°

Wed

11/18

Drizzle

77%

8°

15°

Thu

11/19

Drizzle

69%

7°

14°

Fri

11/20

Drizzle

69%

7°

14°

Good

U.S. Air Quality Index · Dominant: O3

50 100 150 200

Air quality is satisfactory and poses little or no health risk.

Pollutant Breakdown · Today

PM_2.5

Fine particulate matter

28 AQI 5.1 µg/m³

O₃

Ground-level ozone

Dominant

29 AQI 31 ppb

3-Day Outlook

DayAQICategoryO₃PM2.5

Sat 29 Good 29 28

Sun 39 Good 29 39

Mon 49 Good 31 49

About the Air Quality Index

0–50 Good

51–100 Moderate

101–150 Unhealthy for Sensitive Groups

151–200 Unhealthy

201–300 Very Unhealthy

301–500 Hazardous

The U.S. AQI runs 0–500. The overall value equals the highest individual pollutant sub-index, and the dominant pollutant is the one driving it. PM_2.5 (fine particles) is reported in µg/m³ and ozone (O₃) in ppb. Forecast source: NWS NAQFC.

Temp Dewpoint Parcel (SB) CAPE CIN Dry adiabat Moist adiabat Mixing ratio

RAP

Valid Fri Nov 6, 18:00'Z' · F0 · 130 (13 km CONUS/NA)

Hodograph · kt

0–1 1–3 3–6 6–9 km

Instability

SBCAPE68 J/kg

MLCAPE12 J/kg

MUCAPE0 J/kg

SBCIN-0 J/kg

MLCIN-1 J/kg

Lifted Index12.2

Kinematics

0–6 km Shear17 kt

0–1 km Shear7 kt

Eff. Shear—

0–1 km SRH12

0–3 km SRH44

Eff. SRH—

Storm Motion344° @ 30 kt

0–1 km EHI0.0

Composite Parameters

Sig. Tornado0.0

STP (eff)—

Supercell—

K-Index-20.5

Thermo & Levels

PWAT0.37 in

0–3 km LR3.5 °C/km

700–500 LR7.4 °C/km

Total Totals29.9

LCL885 hPa

LFC1004 hPa

EL865 hPa

Freezing Lvl10,951 ft

Williamson County, Illinois, United States

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