Heat Advisory — Stewart, TN, Montgomery, TN, Robertson, TN, Sumner, TN, Macon, TN, Clay, TN, Houston, TN, Humphreys, TN, Dickson, TN, Cheatham, TN, Davidson, TN, Wilson, TN, Trousdale, TN, Smith, TN, Jackson, TN, Putnam, TN, Perry, TN, Hickman, TN, Lewis, TN, Williamson, TN, Maury, TN, Marshall, TN, Rutherford, TN, Cannon, TN, De Kalb, TN, Bedford, TN, Wayne, TN, Lawrence, TN, Giles, TN 8:00 PM

Williamson County, Middle Tennessee, Tennessee, United States

Last updated: 3:52 PM CDT  ·  Refresh
33°C
Feels like 36°
Mostly Clear
▲ 36°  /  ▼ 19°
Wind
4 mph NNW
Humidity
46%
Dew Point
19°
Pressure
29.16 inHg
Visibility
9 mi
UV Index
6.9
Cloud Cover
22%
Sunrise
6:28 AM
Sunset
6:57 PM
Drag to pan · double-click to forecast a point
WeatherAI™ Analysis

WeatherAI Analysis: Williamson County is currently mostly clear at 33°C. Dry conditions are expected through the next 24 hours. Atmospheric instability is elevated (CAPE up to 1362 J/kg) — isolated convective development possible. Sunrise: 6:28AM · Sunset: 6:57PM.

Alerts

Heat Advisory
Stewart, TN, Montgomery, TN, Robertson, TN, Sumner, TN, Macon, TN, Clay, TN, Houston, TN, Humphreys, TN, Dickson, TN, Cheatham, TN, Davidson, TN, Wilson, TN, Trousdale, TN, Smith, TN, Jackson, TN, Putnam, TN, Perry, TN, Hickman, TN, Lewis, TN, Williamson, TN, Maury, TN, Marshall, TN, Rutherford, TN, Cannon, TN, De Kalb, TN, Bedford, TN, Wayne, TN, Lawrence, TN, Giles, TN
Expires 8:00 PM
40 AQI · Good Dominant: O3 Air Quality
Hourly Forecast · Next 24 Hours
Now
33°
7%
4 PM
36°
7%
5 PM
34°
13%
6 PM
32°
12%
7 PM
31°
6%
8 PM
27°
16%
9 PM
27°
3%
10 PM
26°
5%
11 PM
26°
5%
12 AM
24°
5%
1 AM
23°
5%
2 AM
23°
5%
3 AM
22°
5%
4 AM
22°
3%
5 AM
22°
3%
6 AM
22°
3%
7 AM
23°
3%
8 AM
24°
3%
9 AM
26°
3%
10 AM
28°
3%
11 AM
29°
3%
12 PM
32°
3%
1 PM
32°
3%
2 PM
32°
3%
7-Day Forecast
Today
36° 19°
Mostly Clear.
Mon
36° 22°
Mostly Clear.
Tue
38° 22°
Clear.
Wed
36° 21°
Clear.
Thu
38° 23°
Clear.
Fri
37° 22°
Clear with a 60% chance of rain.
Sat
37° 22°
Clear.
TimeTempConditionsPrecipWindHumidity
Now 33° Mostly Clear 7% 4 mph NNW 46%
4 PM 36° Mostly Clear 7% 5 mph NNW 48%
5 PM 34° Mostly Clear 13% 5 mph NNW 51%
6 PM 32° Partly Cloudy 12% 4 mph SSE 56%
7 PM 31° Partly Cloudy 6% 3 mph SSW 60%
8 PM 27° Mostly Clear 16% 3 mph NW 64%
9 PM 27° Mostly Clear 3% 3 mph NNW 67%
10 PM 26° Partly Cloudy 5% 3 mph NNW 69%
11 PM 26° Partly Cloudy 5% 3 mph WNW 72%
12 AM 24° Partly Cloudy 5% 4 mph W 74%
1 AM 23° Partly Cloudy 5% 4 mph NNW 76%
2 AM 23° Partly Cloudy 5% 3 mph N 79%
3 AM 22° Partly Cloudy 5% 3 mph N 83%
4 AM 22° Partly Cloudy 3% 4 mph NNE 85%
5 AM 22° Mostly Clear 3% 4 mph NNE 86%
6 AM 22° Clear 3% 5 mph NE 87%
7 AM 23° Mostly Clear 3% 6 mph NE 82%
8 AM 24° Mostly Clear 3% 6 mph NE 77%
9 AM 26° Partly Cloudy 3% 7 mph NE 73%
10 AM 28° Mostly Clear 3% 7 mph NE 70%
11 AM 29° Mostly Clear 3% 7 mph NE 67%
12 PM 32° Mostly Clear 3% 7 mph NE 64%
1 PM 32° Clear 3% 7 mph NE 63%
2 PM 32° Clear 3% 7 mph NE 62%
15-Day Forecast
Today
9/13
Mostly Clear
12%
19°
36°
Mon
9/14
Mostly Clear
5%
22°
36°
Tue
9/15
Clear
3%
22°
38°
Wed
9/16
Clear
3%
21°
36°
Thu
9/17
Clear
19%
23°
38°
Fri
9/18
Clear
60%
22°
37°
Sat
9/19
Clear
19%
22°
37°
Sun
9/20
Drizzle
60%
20°
34°
Mon
9/21
Drizzle
60%
19°
34°
Tue
9/22
Drizzle
60%
15°
29°
Wed
9/23
Drizzle
60%
10°
29°
Thu
9/24
Drizzle
60%
17°
29°
Fri
9/25
Drizzle
60%
17°
29°
Sat
9/26
Drizzle
60%
16°
29°
Sun
9/27
Drizzle
60%
16°
30°
40
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
36 AQI 6.4 µg/m³
O3
Ground-level ozone
Dominant
40 AQI 44 ppb
3-Day Outlook
DayAQICategoryO₃PM2.5
Mon 40 Good 40 36
Tue 51 Moderate 49 51
Wed 52 Moderate 49 52
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 Sep 13, 19:00'Z' · F0 · 130 (13 km CONUS/NA)
Hodograph · kt
10 20 30 40 SM
0–1 1–3 3–6 6–9 km
Instability
SBCAPE1245 J/kg
MLCAPE297 J/kg
MUCAPE1245 J/kg
SBCIN0 J/kg
MLCIN-15 J/kg
Lifted Index-2.7
Kinematics
0–6 km Shear13 kt
0–1 km Shear4 kt
Eff. Shear11 kt
0–1 km SRH13
0–3 km SRH30
Eff. SRH30
Storm Motion2° @ 20 kt
0–1 km EHI0.1
Composite Parameters
Sig. Tornado0.0
STP (eff)0.0
Supercell0.0
K-Index20.1
Thermo & Levels
PWAT1.40 in
0–3 km LR8.1 °C/km
700–500 LR5.3 °C/km
Total Totals44.2
LCL805 hPa
LFC987 hPa
EL177 hPa
Freezing Lvl15,696 ft