Excessive Heat Watch 7:00 PM

Jefferson County, Missouri, United States

Last updated: 7:44 AM CDT  ·  Refresh
27°C
Feels like 30°
Partly Cloudy
▲ 37°  /  ▼ 24°
Wind
3 mph W
Humidity
86%
Dew Point
24°
Pressure
29.25 inHg
Visibility
6 mi
UV Index
4.4
Cloud Cover
47%
Sunrise
5:59 AM
Sunset
8:17 PM
Drag to pan · double-click to forecast a point
WeatherAI™ Analysis

WeatherAI Analysis: Jefferson County is currently partly cloudy at 27°C. Precipitation is likely — peak probability 51% around 7 PM. Atmospheric instability is elevated (CAPE up to 3886 J/kg) — isolated convective development possible. Sunrise: 5:59AM · Sunset: 8:17PM.

Alerts

Excessive Heat Watch
Expires 7:00 PM
40 AQI · Good Dominant: PM2.5 Air Quality
Hourly Forecast · Next 24 Hours
Now
27°
11%
8 AM
28°
29%
9 AM
31°
21%
10 AM
32°
21%
11 AM
33°
21%
12 PM
35°
21%
1 PM
36°
35%
2 PM
37°
35%
3 PM
37°
35%
4 PM
36°
37%
5 PM
37°
37%
6 PM
34°
38%
7 PM
32°
50%
8 PM
30°
38%
9 PM
28°
17%
10 PM
27°
8%
11 PM
27°
8%
12 AM
26°
3%
1 AM
26°
3%
2 AM
26°
3%
3 AM
26°
3%
4 AM
26°
3%
5 AM
26°
3%
6 AM
26°
3%
7-Day Forecast
Today
37° 24°
Partly Cloudy with a 50% chance of rain.
Mon
40° 25°
Mostly Clear with a 36% chance of rain.
Tue
38° 23°
Partly Cloudy with a 51% chance of rain.
Wed
33° 19°
Mostly Cloudy with a 44% chance of rain.
Thu
34° 19°
Rain, 43% chance.
Fri
32° 20°
Rain, 64% chance.
Sat
32° 18°
Clear with a 52% chance of rain.
TimeTempConditionsPrecipWindHumidity
Now 27° Partly Cloudy 11% 3 mph W 86%
8 AM 28° Partly Cloudy 29% 5 mph W 77%
9 AM 31° Mostly Clear 21% 5 mph W 70%
10 AM 32° Mostly Clear 21% 6 mph W 65%
11 AM 33° Mostly Clear 21% 6 mph WNW 60%
12 PM 35° Mostly Clear 21% 6 mph WNW 55%
1 PM 36° Partly Cloudy 35% 6 mph WNW 52%
2 PM 37° Partly Cloudy 35% 6 mph W 50%
3 PM 37° Partly Cloudy 35% 7 mph W 48%
4 PM 36° Mostly Clear 37% 7 mph W 51%
5 PM 37° Partly Cloudy 37% 6 mph WNW 55%
6 PM 34° Mostly Cloudy 38% 6 mph WSW 60%
7 PM 32° Mostly Cloudy 50% 5 mph WSW 64%
8 PM 30° Partly Cloudy 38% 6 mph E 67%
9 PM 28° Mostly Clear 17% 5 mph SSE 70%
10 PM 27° Mostly Clear 8% 4 mph S 73%
11 PM 27° Mostly Clear 8% 4 mph SSW 76%
12 AM 26° Partly Cloudy 3% 5 mph SSW 79%
1 AM 26° Partly Cloudy 3% 5 mph SSW 78%
2 AM 26° Partly Cloudy 3% 5 mph SW 76%
3 AM 26° Partly Cloudy 3% 5 mph SW 73%
4 AM 26° Partly Cloudy 3% 5 mph SW 74%
5 AM 26° Partly Cloudy 3% 5 mph SW 75%
6 AM 26° Partly Cloudy 3% 4 mph SW 76%
15-Day Forecast
Today
7/26
Partly Cloudy
50%
24°
37°
Mon
7/27
Mostly Clear
36%
25°
40°
Tue
7/28
Partly Cloudy
51%
23°
38°
Wed
7/29
Mostly Cloudy
44%
19°
33°
Thu
7/30
Rain
43%
19°
34°
Fri
7/31
Rain
64%
20°
32°
Sat
8/1
Clear
52%
18°
32°
Sun
8/2
Clear
18%
19°
32°
Mon
8/3
Drizzle
44%
19°
34°
Tue
8/4
Drizzle
51%
21°
35°
Wed
8/5
Drizzle
60%
22°
36°
Thu
8/6
Drizzle
60%
21°
36°
Fri
8/7
Drizzle
60%
21°
34°
Sat
8/8
Drizzle
60%
21°
36°
Sun
8/9
Drizzle
60%
22°
36°
40
Good
U.S. Air Quality Index · Dominant: PM2.5
50 100 150 200

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

Pollutant Breakdown · Today
PM2.5
Fine particulate matter
Dominant
40 AQI 7.3 µg/m³
O3
Ground-level ozone
36 AQI 39 ppb
3-Day Outlook
DayAQICategoryO₃PM2.5
Mon 40 Good 36 40
Tue 33 Good 33 33
Wed 97 Moderate 97 29
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 Sun Jul 26, 11:00'Z' · F0 · 130 (13 km CONUS/NA)
Hodograph · kt
10 20 30 40 SM
0–1 1–3 3–6 6–9 km
Instability
SBCAPE2351 J/kg
MLCAPE2128 J/kg
MUCAPE2351 J/kg
SBCIN-193 J/kg
MLCIN0 J/kg
Lifted Index-4.2
Kinematics
0–6 km Shear11 kt
0–1 km Shear14 kt
Eff. Shear17 kt
0–1 km SRH1
0–3 km SRH-14
Eff. SRH-14
Storm Motion307° @ 22 kt
0–1 km EHI0.0
Composite Parameters
Sig. Tornado0.0
STP (eff)0.0
Supercell0.0
K-Index31.2
Thermo & Levels
PWAT1.68 in
0–3 km LR5.0 °C/km
700–500 LR5.7 °C/km
Total Totals45.9
LCL956 hPa
LFC723 hPa
EL168 hPa
Freezing Lvl16,837 ft