Saint Clair County, Illinois, United States

Last updated: 7:44 AM CDT · Refresh

26°C

Feels like 31°

Mostly Cloudy

▲ 37° / ▼ 23°

Wind

2 mph SW

Humidity

93%

Dew Point

24°

Pressure

29.41 inHg

Visibility

3 mi

UV Index

2.6

Cloud Cover

85%

Sunrise

5:56 AM

Sunset

8:15 PM

Drag to pan · double-click to forecast a point

WeatherAI™ Analysis

WeatherAI Analysis: Saint Clair County is currently mostly cloudy at 26°C. Precipitation is likely — peak probability 66% around 6 PM. Atmospheric instability is elevated (CAPE up to 3986 J/kg) — isolated convective development possible. Sunrise: 5:56AM · Sunset: 8:15PM.

54 AQI · Moderate Dominant: PM2.5 Air Quality

Hourly Forecast · Next 24 Hours

Now

26°

30%

8 AM

27°

33%

9 AM

29°

25%

10 AM

31°

25%

11 AM

32°

36%

12 PM

33°

36%

1 PM

35°

43%

2 PM

36°

43%

3 PM

37°

48%

4 PM

36°

57%

5 PM

35°

57%

6 PM

32°

66%

7 PM

30°

53%

8 PM

28°

57%

9 PM

27°

34%

10 PM

27°

17%

11 PM

26°

17%

12 AM

26°

1 AM

26°

2 AM

25°

3 AM

24°

4 AM

24°

5 AM

24°

6 AM

24°

7-Day Forecast

Today

37° 23°

Mostly Cloudy with a 57% chance of rain.

Mon

37° 23°

Partly Cloudy with a 30% chance of rain.

Tue

35° 21°

Mostly Clear with a 25% chance of rain.

Wed

31° 18°

Mostly Clear with a 42% chance of rain.

Thu

30° 18°

Clear.

Fri

28° 20°

Rain, 82% chance.

Sat

30° 18°

Rain, 63% chance.

+ Feels like

TimeTempConditionsPrecipWindHumidity

Now 26° Mostly Cloudy 30% 2 mph SW 93%

8 AM 27° Mostly Cloudy 33% 3 mph WSW 86%

9 AM 29° Partly Cloudy 25% 4 mph WSW 80%

10 AM 31° Partly Cloudy 25% 4 mph WSW 74%

11 AM 32° Partly Cloudy 36% 4 mph WSW 69%

12 PM 33° Mostly Cloudy 36% 5 mph WSW 64%

1 PM 35° Partly Cloudy 43% 6 mph WSW 60%

2 PM 36° Mostly Cloudy 43% 6 mph WSW 56%

3 PM 37° Partly Cloudy 48% 6 mph WSW 52%

4 PM 36° Partly Cloudy 57% 5 mph SW 57%

5 PM 35° Mostly Cloudy 57% 6 mph SSW 66%

6 PM 32° Rain 66% 9 mph SSW 76%

7 PM 30° Overcast 53% 7 mph SSE 78%

8 PM 28° Mostly Cloudy 57% 5 mph S 78%

9 PM 27° Partly Cloudy 34% 7 mph S 77%

10 PM 27° Partly Cloudy 17% 6 mph SSW 78%

11 PM 26° Mostly Clear 17% 5 mph SW 80%

12 AM 26° Mostly Clear 8% 6 mph SW 82%

1 AM 26° Mostly Clear 3% 5 mph SSW 84%

2 AM 25° Partly Cloudy 3% 5 mph SSW 87%

3 AM 24° Partly Cloudy 3% 6 mph S 90%

4 AM 24° Partly Cloudy 3% 5 mph S 90%

5 AM 24° Partly Cloudy 3% 6 mph SSE 90%

6 AM 24° Partly Cloudy 3% 6 mph SE 90%

15-Day Forecast

Today

7/26

Mostly Cloudy

57%

23°

37°

Mon

7/27

Partly Cloudy

30%

23°

37°

Tue

7/28

Mostly Clear

25%

21°

35°

Wed

7/29

Mostly Clear

42%

18°

31°

Thu

7/30

Clear

16%

18°

30°

Fri

7/31

Rain

82%

20°

28°

Sat

8/1

Rain

63%

18°

30°

Sun

8/2

Drizzle

42%

19°

29°

Mon

8/3

Drizzle

44%

19°

31°

Tue

8/4

Drizzle

51%

21°

32°

Wed

8/5

Drizzle

60%

21°

33°

Thu

8/6

Drizzle

60%

21°

32°

Fri

8/7

Drizzle

60%

20°

32°

Sat

8/8

Drizzle

60%

20°

33°

Sun

8/9

Drizzle

60%

21°

34°

Moderate

U.S. Air Quality Index · Dominant: PM2.5

50 100 150 200

Air quality is acceptable. Unusually sensitive people should consider limiting prolonged outdoor exertion.

Pollutant Breakdown · Today

PM_2.5

Fine particulate matter

Dominant

54 AQI 10.7 µg/m³

O₃

Ground-level ozone

47 AQI 51 ppb

3-Day Outlook

DayAQICategoryO₃PM2.5

Mon 54 Moderate 47 54

Tue 52 Moderate 40 52

Wed 44 Good 44 42

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 Sun Jul 26, 11:00'Z' · F0 · 130 (13 km CONUS/NA)

Hodograph · kt

0–1 1–3 3–6 6–9 km

Instability

SBCAPE2066 J/kg

MLCAPE2245 J/kg

MUCAPE2520 J/kg

SBCIN-192 J/kg

MLCIN0 J/kg

Lifted Index-3.9

Kinematics

0–6 km Shear14 kt

0–1 km Shear14 kt

Eff. Shear21 kt

0–1 km SRH4

0–3 km SRH-14

Eff. SRH-14

Storm Motion304° @ 23 kt

0–1 km EHI0.1

Composite Parameters

Sig. Tornado0.0

STP (eff)0.0

Supercell0.0

K-Index31.4

Thermo & Levels

PWAT1.80 in

0–3 km LR4.5 °C/km

700–500 LR5.8 °C/km

Total Totals46.4

LCL980 hPa

LFC720 hPa

EL175 hPa

Freezing Lvl16,847 ft

Saint Clair County, Illinois, United States

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