Chester County, Pennsylvania, United States

Last updated: 6:21 PM CDT · Refresh

23°C

Feels like 24°

Rain

▲ 28° / ▼ 21°

Wind

8 mph S

Humidity

93%

Dew Point

21°

Pressure

29.18 inHg

Visibility

9 mi

UV Index

1.1

Cloud Cover

94%

Sunrise

5:51 AM

Sunset

8:26 PM

Drag to pan · double-click to forecast a point

WeatherAI™ Analysis

WeatherAI Analysis: Chester County is currently rain at 23°C. Precipitation is likely — peak probability 71% around 8 PM. Atmospheric instability is elevated (CAPE up to 1111 J/kg) — isolated convective development possible. Sunrise: 5:51AM · Sunset: 8:26PM.

69 AQI · Moderate Dominant: PM2.5 Air Quality

Hourly Forecast · Next 24 Hours

Now

23°

70%

8 PM

23°

71%

9 PM

23°

71%

10 PM

23°

66%

11 PM

23°

54%

12 AM

22°

46%

1 AM

22°

51%

2 AM

22°

39%

3 AM

22°

39%

4 AM

21°

35%

5 AM

21°

40%

6 AM

21°

40%

7 AM

22°

42%

8 AM

22°

43%

9 AM

23°

46%

10 AM

24°

33%

11 AM

24°

30%

12 PM

24°

33%

1 PM

26°

29%

2 PM

27°

26%

3 PM

27°

27%

4 PM

27°

24%

5 PM

27°

22%

6 PM

26°

24%

7-Day Forecast

Tonight

28° 21°

Rain, 70% chance.

Wed

28° 18°

Mostly Clear with a 51% chance of rain.

Thu

27° 16°

Mostly Clear.

Fri

27° 17°

Partly Cloudy.

Sat

28° 16°

Partly Cloudy with a 21% chance of rain.

Sun

29° 18°

Rain, 71% chance.

Mon

29° 19°

Drizzle, 63% chance.

+ Feels like

TimeTempConditionsPrecipWindHumidity

Now 23° Rain 70% 8 mph S 93%

8 PM 23° Rain 71% 10 mph SSW 95%

9 PM 23° Rain 71% 7 mph SSW 94%

10 PM 23° Overcast 66% 6 mph SSW 94%

11 PM 23° Mostly Cloudy 54% 8 mph SSW 94%

12 AM 22° Drizzle 46% 9 mph SSW 94%

1 AM 22° Mostly Cloudy 51% 11 mph SW 93%

2 AM 22° Partly Cloudy 39% 10 mph SW 92%

3 AM 22° Mostly Cloudy 39% 10 mph SSW 94%

4 AM 21° Mostly Cloudy 35% 9 mph SSW 95%

5 AM 21° Partly Cloudy 40% 8 mph SW 95%

6 AM 21° Partly Cloudy 40% 8 mph SW 92%

7 AM 22° Partly Cloudy 42% 8 mph WSW 89%

8 AM 22° Rain 43% 9 mph WSW 85%

9 AM 23° Mostly Clear 46% 10 mph W 80%

10 AM 24° Mostly Clear 33% 10 mph W 75%

11 AM 24° Mostly Clear 30% 10 mph W 71%

12 PM 24° Mostly Clear 33% 10 mph W 68%

1 PM 26° Mostly Clear 29% 10 mph W 65%

2 PM 27° Mostly Clear 26% 10 mph WNW 62%

3 PM 27° Mostly Clear 27% 10 mph W 61%

4 PM 27° Mostly Clear 24% 10 mph W 60%

5 PM 27° Mostly Clear 22% 10 mph W 60%

6 PM 26° Clear 24% 9 mph WNW 60%

15-Day Forecast

Today

7/21

Rain

70%

21°

28°

Wed

7/22

Mostly Clear

51%

18°

28°

Thu

7/23

Mostly Clear

16°

27°

Fri

7/24

Partly Cloudy

14%

17°

27°

Sat

7/25

Partly Cloudy

21%

16°

28°

Sun

7/26

Rain

71%

18°

29°

Mon

7/27

Drizzle

63%

19°

29°

Tue

7/28

Drizzle

63%

18°

28°

Wed

7/29

Drizzle

68%

18°

27°

Thu

7/30

Drizzle

68%

18°

29°

Fri

7/31

Drizzle

46%

19°

28°

Sat

8/1

Drizzle

60%

18°

28°

Sun

8/2

Drizzle

60%

18°

29°

Mon

8/3

Drizzle

60%

19°

29°

Tue

8/4

Rain

90%

19°

30°

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

PM_2.5

Fine particulate matter

Dominant

69 AQI 18.9 µg/m³

O₃

Ground-level ozone

35 AQI 39 ppb

3-Day Outlook

DayAQICategoryO₃PM2.5

Wed 69 Moderate 35 69

Thu 50 Good 40 50

Fri 52 Moderate 43 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. PM_2.5 (fine particles) is reported in µg/m³ and ozone (O₃) in ppb. Forecast source: NWS NAQFC.

Temp Dewpoint Parcel (SB) CAPE CIN Dry adiabat Moist adiabat Mixing ratio

RAP

Valid Tue Jul 21, 22:00'Z' · F0 · 130 (13 km CONUS/NA)

Hodograph · kt

0–1 1–3 3–6 6–9 km

Instability

SBCAPE477 J/kg

MLCAPE1075 J/kg

MUCAPE1671 J/kg

SBCIN-188 J/kg

MLCIN0 J/kg

Lifted Index-3.5

Kinematics

0–6 km Shear37 kt

0–1 km Shear27 kt

Eff. Shear39 kt

0–1 km SRH113

0–3 km SRH172

Eff. SRH172

Storm Motion228° @ 34 kt

0–1 km EHI0.3

Composite Parameters

Sig. Tornado0.4

STP (eff)0.1

Supercell5.8

K-Index35.8

Thermo & Levels

PWAT2.04 in

0–3 km LR4.7 °C/km

700–500 LR6.4 °C/km

Total Totals50.0

LCL968 hPa

LFC702 hPa

EL282 hPa

Freezing Lvl13,520 ft

Chester County, Pennsylvania, United States

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