Severe Thunderstorm Watch 12:00 AM

Frederick County, Virginia, United States

Last updated: 11:45 PM CDT  ·  Refresh
20°C
Feels like 21°
Mostly Cloudy
▲ 27°  /  ▼ 14°
Wind
7 mph SSW
Humidity
92%
Dew Point
18°
Pressure
28.80 inHg
Visibility
10 mi
UV Index
0.0
Cloud Cover
77%
Sunrise
6:04 AM
Sunset
8:33 PM
Drag to pan · double-click to forecast a point
WeatherAI™ Analysis

WeatherAI Analysis: Frederick County is currently mostly cloudy at 20°C. Dry conditions are expected through the next 24 hours. Atmospheric instability is elevated (CAPE up to 665 J/kg) — isolated convective development possible. Sunrise: 6:04AM · Sunset: 8:33PM.

Alerts

Severe Thunderstorm Watch
Expires 12:00 AM
56 AQI · Moderate Dominant: PM2.5 Air Quality
Hourly Forecast · Next 24 Hours
Now
20°
30%
1 AM
20°
13%
2 AM
20°
7%
3 AM
20°
11%
4 AM
20°
13%
5 AM
19°
23%
6 AM
19°
12%
7 AM
21°
13%
8 AM
22°
13%
9 AM
22°
16%
10 AM
24°
16%
11 AM
24°
8%
12 PM
26°
6%
1 PM
27°
6%
2 PM
27°
3%
3 PM
27°
3%
4 PM
26°
3%
5 PM
27°
3%
6 PM
26°
3%
7 PM
24°
3%
8 PM
23°
3%
9 PM
22°
3%
10 PM
21°
3%
11 PM
21°
3%
7-Day Forecast
Today
27° 14°
Mostly Clear with a 30% chance of rain.
Thu
27° 14°
Clear.
Fri
27° 14°
Mostly Cloudy.
Sat
26° 17°
Overcast.
Sun
32° 16°
Rain, 70% chance.
Mon
33° 19°
Rain, 71% chance.
Tue
37° 17°
Rain, 63% chance.
TimeTempConditionsPrecipWindHumidity
Now 20° Mostly Cloudy 30% 7 mph SSW 92%
1 AM 20° Mostly Cloudy 13% 6 mph SSW 93%
2 AM 20° Mostly Cloudy 7% 6 mph SSW 92%
3 AM 20° Partly Cloudy 11% 5 mph SW 92%
4 AM 20° Mostly Clear 13% 5 mph SW 92%
5 AM 19° Mostly Clear 23% 5 mph WSW 91%
6 AM 19° Mostly Clear 12% 5 mph WSW 89%
7 AM 21° Mostly Clear 13% 6 mph WSW 86%
8 AM 22° Mostly Clear 13% 8 mph W 78%
9 AM 22° Mostly Clear 16% 9 mph W 70%
10 AM 24° Mostly Clear 16% 11 mph W 62%
11 AM 24° Mostly Clear 8% 11 mph W 56%
12 PM 26° Mostly Clear 6% 11 mph W 53%
1 PM 27° Partly Cloudy 6% 11 mph W 50%
2 PM 27° Mostly Clear 3% 11 mph W 49%
3 PM 27° Mostly Clear 3% 11 mph WNW 49%
4 PM 26° Clear 3% 11 mph WNW 49%
5 PM 27° Mostly Clear 3% 10 mph WNW 52%
6 PM 26° Mostly Clear 3% 9 mph WNW 55%
7 PM 24° Partly Cloudy 3% 8 mph NW 58%
8 PM 23° Partly Cloudy 3% 8 mph NW 61%
9 PM 22° Partly Cloudy 3% 7 mph NW 63%
10 PM 21° Partly Cloudy 3% 7 mph NW 66%
11 PM 21° Partly Cloudy 3% 7 mph NW 67%
15-Day Forecast
Today
7/22
Mostly Clear
30%
14°
27°
Thu
7/23
Clear
3%
14°
27°
Fri
7/24
Mostly Cloudy
18%
14°
27°
Sat
7/25
Overcast
19%
17°
26°
Sun
7/26
Rain
70%
16°
32°
Mon
7/27
Rain
71%
19°
33°
Tue
7/28
Rain
63%
17°
37°
Wed
7/29
Drizzle
53%
16°
31°
Thu
7/30
Drizzle
44%
15°
30°
Fri
7/31
Drizzle
51%
15°
30°
Sat
8/1
Drizzle
60%
16°
29°
Sun
8/2
Drizzle
60%
16°
31°
Mon
8/3
Drizzle
60%
17°
32°
Tue
8/4
Drizzle
60%
18°
33°
Wed
8/5
Drizzle
60%
18°
32°
56
Moderate
U.S. Air Quality Index · Dominant: PM2.5
50 100 150 200

Air quality is acceptable. Unusually sensitive people should consider limiting prolonged outdoor exertion.

Pollutant Breakdown · Today
PM2.5
Fine particulate matter
Dominant
56 AQI 11.6 µg/m³
O3
Ground-level ozone
31 AQI 33 ppb
3-Day Outlook
DayAQICategoryO₃PM2.5
Today 56 Moderate 31 56
Thu 36 Good 36 36
Fri 43 Good 36 43
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 LCL0°C Temperature (°C) Pressure (hPa)
Temp Dewpoint Parcel (SB) CAPE CIN Dry adiabat Moist adiabat Mixing ratio
RAP
Valid Wed Jul 22, 03:00'Z' · F0 · 130 (13 km CONUS/NA)
Hodograph · kt
10 20 30 40 50 60 70 80 90 SM
0–1 1–3 3–6 6–9 km
Instability
SBCAPE0 J/kg
MLCAPE33 J/kg
MUCAPE181 J/kg
SBCIN-6111 J/kg
MLCIN0 J/kg
Lifted Index0.8
Kinematics
0–6 km Shear40 kt
0–1 km Shear30 kt
Eff. Shear1 kt
0–1 km SRH-50
0–3 km SRH-23
Eff. SRH12
Storm Motion230° @ 34 kt
0–1 km EHI-0.0
Composite Parameters
Sig. Tornado-0.0
STP (eff)0.0
Supercell0.0
K-Index38.3
Thermo & Levels
PWAT1.67 in
0–3 km LR4.4 °C/km
700–500 LR5.9 °C/km
Total Totals48.4
LCL952 hPa
LFC—
EL—
Freezing Lvl13,691 ft