Lewis and Clark County, Montana, United States

Last updated: 2:45 PM CDT  ·  Refresh
12°C
Feels like 9°
Partly Cloudy
▲ 14°  /  ▼ 2°
Wind
8 mph WSW
Humidity
64%
Dew Point
7°
Pressure
24.02 inHg
Visibility
9 mi
UV Index
7.4
Cloud Cover
46%
Sunrise
7:03 AM
Sunset
7:45 PM
Drag to pan · double-click to forecast a point
WeatherAI™ Analysis

WeatherAI Analysis: Lewis and Clark County is currently partly cloudy at 12°C. Precipitation is likely — peak probability 53% around 6 AM. Sunrise: 7:03AM · Sunset: 7:45PM.

Alerts

No active alerts for this location.
33 AQI · Good Dominant: O3 Air Quality
Hourly Forecast · Next 24 Hours
Now
12°
31%
2 PM
13°
39%
3 PM
13°
34%
4 PM
12°
37%
5 PM
12°
19%
6 PM
12°
20%
7 PM
10°
27%
8 PM
9°
27%
9 PM
8°
27%
10 PM
7°
38%
11 PM
7°
14%
12 AM
6°
14%
1 AM
4°
20%
2 AM
3°
20%
3 AM
3°
24%
4 AM
3°
50%
5 AM
2°
50%
6 AM
2°
53%
7 AM
2°
52%
8 AM
3°
52%
9 AM
4°
42%
10 AM
4°
41%
11 AM
6°
41%
12 PM
6°
40%
7-Day Forecast
Today
14° 2°
Partly Cloudy with a 38% chance of rain.
Mon
12° 2°
Rain, 52% chance.
Tue
15° 3°
Partly Cloudy.
Wed
18° 4°
Clear with a 38% chance of rain.
Thu
25° 8°
Clear with a 35% chance of rain.
Fri
22° 8°
Drizzle, 60% chance.
Sat
22° 8°
Drizzle, 60% chance.
TimeTempConditionsPrecipWindHumidity
Now 12° Partly Cloudy 31% 8 mph WSW 64%
2 PM 13° Mostly Clear 39% 12 mph W 60%
3 PM 13° Rain 34% 13 mph W 55%
4 PM 12° Mostly Clear 37% 12 mph W 53%
5 PM 12° Mostly Clear 19% 11 mph W 53%
6 PM 12° Partly Cloudy 20% 10 mph W 55%
7 PM 10° Mostly Cloudy 27% 8 mph W 60%
8 PM 9° Overcast 27% 7 mph W 66%
9 PM 8° Overcast 27% 8 mph W 68%
10 PM 7° Rain 38% 8 mph W 69%
11 PM 7° Mostly Cloudy 14% 8 mph WSW 70%
12 AM 6° Partly Cloudy 14% 9 mph W 73%
1 AM 4° Mostly Cloudy 20% 6 mph W 75%
2 AM 3° Mostly Cloudy 20% 7 mph W 78%
3 AM 3° Mostly Cloudy 24% 12 mph W 80%
4 AM 3° Mostly Cloudy 50% 15 mph WSW 82%
5 AM 2° Mostly Cloudy 50% 16 mph WSW 84%
6 AM 2° Rain 53% 17 mph WSW 85%
7 AM 2° Rain 52% 18 mph W 85%
8 AM 3° Rain 52% 19 mph W 85%
9 AM 4° Rain 42% 19 mph W 84%
10 AM 4° Rain 41% 19 mph W 82%
11 AM 6° Rain 41% 19 mph W 80%
12 PM 6° Rain 40% 18 mph W 79%
15-Day Forecast
Today
9/13
Partly Cloudy
38%
2°
14°
Mon
9/14
Rain
52%
2°
12°
Tue
9/15
Partly Cloudy
8%
3°
15°
Wed
9/16
Clear
38%
4°
18°
Thu
9/17
Clear
35%
8°
25°
Fri
9/18
Drizzle
60%
8°
22°
Sat
9/19
Drizzle
60%
8°
22°
Sun
9/20
Clear
60%
8°
22°
Mon
9/21
Clear
25%
8°
22°
Tue
9/22
Clear
14%
8°
22°
Wed
9/23
Clear
25%
8°
22°
Thu
9/24
Drizzle
60%
6°
19°
Fri
9/25
Drizzle
60%
6°
18°
Sat
9/26
Drizzle
60%
6°
17°
Sun
9/27
Drizzle
60%
5°
18°
33
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
16 AQI 2.8 µg/m³
O3
Ground-level ozone
Dominant
33 AQI 36 ppb
3-Day Outlook
DayAQICategoryO₃PM2.5
Mon 33 Good 33 16
Tue 32 Good 32 11
Wed 28 Good 28 11
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, 18:00'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
SBCAPE102 J/kg
MLCAPE22 J/kg
MUCAPE102 J/kg
SBCIN0 J/kg
MLCIN-0 J/kg
Lifted Index-0.7
Kinematics
0–6 km Shear55 kt
0–1 km Shear14 kt
Eff. Shear33 kt
0–1 km SRH-16
0–3 km SRH87
Eff. SRH87
Storm Motion232° @ 39 kt
0–1 km EHI-0.0
Composite Parameters
Sig. Tornado0.0
STP (eff)0.0
Supercell0.2
K-Index—
Thermo & Levels
PWAT0.59 in
0–3 km LR7.0 °C/km
700–500 LR6.3 °C/km
Total Totals—
LCL747 hPa
LFC813 hPa
EL415 hPa
Freezing Lvl5,433 ft