Severe Thunderstorm Watch 11:00 PM Areal Flood Watch 1:00 AM

Montgomery County, Maryland, United States

Last updated: 10:33 PM CDT  ·  Refresh
21°C
Feels like 23°
Overcast
▲ 29°  /  ▼ 20°
Wind
7 mph S
Humidity
93%
Dew Point
20°
Pressure
29.29 inHg
Visibility
6 mi
UV Index
0.0
Cloud Cover
93%
Sunrise
5:59 AM
Sunset
8:30 PM
Drag to pan · double-click to forecast a point
WeatherAI™ Analysis

WeatherAI Analysis: Montgomery County is currently overcast at 21°C. Dry conditions are expected through the next 24 hours. Atmospheric instability is elevated (CAPE up to 973 J/kg) — isolated convective development possible. Sunrise: 5:59AM · Sunset: 8:30PM.

Alerts

Severe Thunderstorm Watch
Expires 11:00 PM
Areal Flood Watch
Expires 1:00 AM
35 AQI · Good Dominant: O3 Air Quality
Hourly Forecast · Next 24 Hours
Now
21°
29%
12 AM
22°
34%
1 AM
22°
36%
2 AM
22°
34%
3 AM
22°
25%
4 AM
21°
29%
5 AM
20°
35%
6 AM
21°
32%
7 AM
22°
21%
8 AM
23°
11%
9 AM
24°
16%
10 AM
26°
17%
11 AM
26°
26%
12 PM
27°
23%
1 PM
28°
23%
2 PM
29°
23%
3 PM
28°
24%
4 PM
28°
24%
5 PM
28°
22%
6 PM
27°
18%
7 PM
26°
19%
8 PM
26°
19%
9 PM
24°
19%
10 PM
23°
19%
7-Day Forecast
Tonight
29° 20°
Overcast with a 29% chance of rain.
Wed
29° 20°
Mostly Clear with a 35% chance of rain.
Thu
27° 17°
Clear.
Fri
28° 16°
Mostly Cloudy.
Sat
28° 18°
Mostly Clear.
Sun
31° 18°
Rain, 70% chance.
Mon
33° 20°
Rain, 71% chance.
TimeTempConditionsPrecipWindHumidity
Now 21° Overcast 29% 7 mph S 93%
12 AM 22° Overcast 34% 7 mph SSW 93%
1 AM 22° Overcast 36% 6 mph SSW 94%
2 AM 22° Mostly Cloudy 34% 7 mph SSW 95%
3 AM 22° Partly Cloudy 25% 6 mph SSW 96%
4 AM 21° Mostly Cloudy 29% 6 mph SSW 96%
5 AM 20° Mostly Cloudy 35% 5 mph SW 96%
6 AM 21° Partly Cloudy 32% 6 mph SW 95%
7 AM 22° Mostly Clear 21% 6 mph WSW 94%
8 AM 23° Mostly Clear 11% 7 mph WSW 88%
9 AM 24° Mostly Clear 16% 8 mph W 79%
10 AM 26° Mostly Clear 17% 9 mph W 71%
11 AM 26° Mostly Clear 26% 10 mph W 64%
12 PM 27° Mostly Clear 23% 11 mph W 59%
1 PM 28° Mostly Clear 23% 12 mph W 54%
2 PM 29° Mostly Clear 23% 12 mph W 51%
3 PM 28° Clear 24% 11 mph WNW 51%
4 PM 28° Clear 24% 11 mph WNW 51%
5 PM 28° Clear 22% 10 mph WNW 53%
6 PM 27° Mostly Clear 18% 9 mph WNW 58%
7 PM 26° Mostly Clear 19% 7 mph WNW 62%
8 PM 26° Mostly Clear 19% 7 mph NW 62%
9 PM 24° Partly Cloudy 19% 7 mph NW 62%
10 PM 23° Partly Cloudy 19% 8 mph NNW 60%
15-Day Forecast
Today
7/21
Overcast
29%
20°
29°
Wed
7/22
Mostly Clear
35%
20°
29°
Thu
7/23
Clear
3%
17°
27°
Fri
7/24
Mostly Cloudy
19%
16°
28°
Sat
7/25
Mostly Clear
19%
18°
28°
Sun
7/26
Rain
70%
18°
31°
Mon
7/27
Rain
71%
20°
33°
Tue
7/28
Thunderstorm
63%
19°
34°
Wed
7/29
Rain
68%
18°
30°
Thu
7/30
Drizzle
44%
17°
29°
Fri
7/31
Drizzle
60%
17°
30°
Sat
8/1
Drizzle
60%
19°
31°
Sun
8/2
Drizzle
60%
20°
31°
Mon
8/3
Drizzle
60%
21°
32°
Tue
8/4
Drizzle
60%
21°
33°
35
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
26 AQI 4.7 µg/m³
O3
Ground-level ozone
Dominant
35 AQI 38 ppb
3-Day Outlook
DayAQICategoryO₃PM2.5
Today 35 Good 35 26
Thu 37 Good 37 11
Fri 35 Good 35 18
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 Wed Jul 22, 02:00'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
SBCAPE13 J/kg
MLCAPE83 J/kg
MUCAPE206 J/kg
SBCIN-269 J/kg
MLCIN0 J/kg
Lifted Index-0.2
Kinematics
0–6 km Shear39 kt
0–1 km Shear33 kt
Eff. Shear10 kt
0–1 km SRH-21
0–3 km SRH-13
Eff. SRH-5
Storm Motion240° @ 37 kt
0–1 km EHI-0.0
Composite Parameters
Sig. Tornado0.0
STP (eff)0.0
Supercell0.0
K-Index32.7
Thermo & Levels
PWAT1.86 in
0–3 km LR4.3 °C/km
700–500 LR5.9 °C/km
Total Totals45.8
LCL976 hPa
LFC557 hPa
EL419 hPa
Freezing Lvl14,564 ft