Severe Thunderstorm Watch 10:00 PM Severe Thunderstorm Watch 10:00 PM

Mercer County, Illinois, United States

Last updated: 9:09 PM CDT  ·  Refresh
23°C
Feels like 26°
Clear
▲ 29°  /  ▼ 16°
Wind
6 mph WNW
Humidity
86%
Dew Point
21°
Pressure
29.22 inHg
Visibility
10 mi
UV Index
0.0
Cloud Cover
0%
Sunrise
6:18 AM
Sunset
7:52 PM
Drag to pan · double-click to forecast a point
WeatherAI™ Analysis

WeatherAI Analysis: Mercer County is currently clear at 23°C. Dry conditions are expected through the next 24 hours. Atmospheric instability is elevated (CAPE up to 2051 J/kg) — isolated convective development possible. Sunrise: 6:18AM · Sunset: 7:52PM.

Alerts

Severe Thunderstorm Watch
Expires 10:00 PM
Severe Thunderstorm Watch
Expires 10:00 PM
31 AQI · Good Dominant: O3 Air Quality
Hourly Forecast · Next 24 Hours
Now
23°
26%
10 PM
23°
14%
11 PM
22°
14%
12 AM
21°
14%
1 AM
19°
3%
2 AM
19°
3%
3 AM
18°
3%
4 AM
18°
3%
5 AM
17°
3%
6 AM
17°
3%
7 AM
17°
3%
8 AM
19°
3%
9 AM
22°
5%
10 AM
23°
5%
11 AM
24°
5%
12 PM
26°
5%
1 PM
28°
5%
2 PM
28°
8%
3 PM
28°
16%
4 PM
28°
16%
5 PM
28°
16%
6 PM
27°
13%
7 PM
26°
12%
8 PM
24°
13%
7-Day Forecast
Tonight
29° 16°
Clear with a 26% chance of rain.
Sat
28° 16°
Clear.
Sun
27° 13°
Clear.
Mon
24° 14°
Overcast with a 54% chance of rain.
Tue
27° 14°
Clear with a 64% chance of rain.
Wed
29° 18°
Rain, 64% chance.
Thu
28° 17°
Clear with a 29% chance of rain.
TimeTempConditionsPrecipWindHumidity
Now 23° Clear 26% 6 mph WNW 86%
10 PM 23° Clear 14% 8 mph NNW 81%
11 PM 22° Clear 14% 7 mph NNW 82%
12 AM 21° Clear 14% 7 mph NNW 84%
1 AM 19° Clear 3% 7 mph NNW 86%
2 AM 19° Clear 3% 6 mph NNW 88%
3 AM 18° Clear 3% 6 mph NNW 88%
4 AM 18° Clear 3% 5 mph NNW 88%
5 AM 17° Clear 3% 5 mph NNW 89%
6 AM 17° Mostly Clear 3% 4 mph NW 90%
7 AM 17° Mostly Clear 3% 4 mph WNW 90%
8 AM 19° Mostly Clear 3% 6 mph WNW 85%
9 AM 22° Clear 5% 6 mph WNW 80%
10 AM 23° Clear 5% 8 mph WNW 75%
11 AM 24° Clear 5% 10 mph WNW 69%
12 PM 26° Clear 5% 12 mph NW 65%
1 PM 28° Clear 5% 13 mph NW 61%
2 PM 28° Clear 8% 12 mph NW 61%
3 PM 28° Mostly Clear 16% 12 mph NW 61%
4 PM 28° Mostly Clear 16% 12 mph NW 61%
5 PM 28° Clear 16% 11 mph NW 65%
6 PM 27° Clear 13% 10 mph NW 69%
7 PM 26° Clear 12% 10 mph NW 71%
8 PM 24° Clear 13% 8 mph NW 73%
15-Day Forecast
Today
8/21
Clear
26%
16°
29°
Sat
8/22
Clear
16%
16°
28°
Sun
8/23
Clear
3%
13°
27°
Mon
8/24
Overcast
54%
14°
24°
Tue
8/25
Clear
64%
14°
27°
Wed
8/26
Rain
64%
18°
29°
Thu
8/27
Clear
29%
17°
28°
Fri
8/28
Clear
31%
17°
27°
Sat
8/29
Thunderstorm
69%
17°
31°
Sun
8/30
Drizzle
68%
19°
32°
Mon
8/31
Drizzle
60%
19°
32°
Tue
9/1
Drizzle
60%
20°
31°
Wed
9/2
Drizzle
60%
19°
30°
Thu
9/3
Drizzle
60%
18°
29°
Fri
9/4
Clear
60%
18°
30°
31
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
PM2.5
Fine particulate matter
27 AQI 4.8 µg/m³
O3
Ground-level ozone
Dominant
31 AQI 35 ppb
3-Day Outlook
DayAQICategoryO₃PM2.5
Today 31 Good 31 27
Sun 36 Good 36 28
Mon 31 Good 31 7
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. PM2.5 (fine particles) is reported in µg/m³ and ozone (O3) in ppb. Forecast source: NWS NAQFC.

1000850700500400300250200150100 -40-30-20-10010203040 0.41247101624 LCLLFCEL0°C Temperature (°C) Pressure (hPa)
Temp Dewpoint Parcel (SB) CAPE CIN Dry adiabat Moist adiabat Mixing ratio
RAP
Valid Fri Aug 21, 23:00'Z' · F0 · 130 (13 km CONUS/NA)
Hodograph · kt
10 20 30 40 50 60 70 80 SM
0–1 1–3 3–6 6–9 km
Instability
SBCAPE2132 J/kg
MLCAPE2617 J/kg
MUCAPE3664 J/kg
SBCIN-168 J/kg
MLCIN-54 J/kg
Lifted Index-5.8
Kinematics
0–6 km Shear24 kt
0–1 km Shear19 kt
Eff. Shear23 kt
0–1 km SRH116
0–3 km SRH140
Eff. SRH140
Storm Motion342° @ 26 kt
0–1 km EHI1.5
Composite Parameters
Sig. Tornado0.0
STP (eff)0.0
Supercell6.1
K-Index28.8
Thermo & Levels
PWAT1.48 in
0–3 km LR5.5 °C/km
700–500 LR6.5 °C/km
Total Totals52.8
LCL961 hPa
LFC825 hPa
EL209 hPa
Freezing Lvl13,100 ft