Hourly Weather Forecast for Lancaster, Pennsylvania

Hourly Weather | Today › Wednesday, May 20, 2026

Active Weather Warnings

Severe Thunderstorm Watch

Lancaster, Pennsylvania

8 PM

73°

Feels Like 77°

Humidity: 87%

UV Index: 0

Wind: 7 mph

9 PM

72°

Feels Like 72°

Humidity: 88%

UV Index: 0

Wind: 7 mph

10 PM

70°

Feels Like 68°

Humidity: 85%

UV Index: 0

Wind: 8 mph

11 PM

70°

Feels Like 68°

Humidity: 81%

UV Index: 0

Wind: 8 mph

Hourly Air Quality Forecast - AQI (US EPA)

8 PM

24 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 3.12 µg/m³
PM₁₀: 3.96 µg/m³
O₃: 0.026 ppm
NO₂: 9.2 ppb
SO₂: 0.8 ppb
CO: 0.16 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

9 PM

21 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 3.08 µg/m³
PM₁₀: 4 µg/m³
O₃: 0.023 ppm
NO₂: 8.8 ppb
SO₂: 0.7 ppb
CO: 0.16 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

10 PM

19 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 3.11 µg/m³
PM₁₀: 4.17 µg/m³
O₃: 0.020 ppm
NO₂: 8.5 ppb
SO₂: 0.6 ppb
CO: 0.16 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

11 PM

16 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 3.26 µg/m³
PM₁₀: 4.39 µg/m³
O₃: 0.018 ppm
NO₂: 8.3 ppb
SO₂: 0.5 ppb
CO: 0.16 ppm

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

Current Real-Time Air Quality Report

Weather Alerts and Warnings for Lancaster

Severe Future Possible

Severe Thunderstorm Watch

Severe Thunderstorm Watch issued May 20 at 12:40PM EDT until May 20 at 8:00PM EDT by NWS State College PA

May 20, 12:40 PM → May 20, 8:00 PM

THE NATIONAL WEATHER SERVICE HAS ISSUED SEVERE THUNDERSTORM WATCH
234 IN EFFECT UNTIL 8 PM EDT THIS EVENING FOR THE FOLLOWING AREAS

IN PENNSYLVANIA THIS WATCH INCLUDES 18 COUNTIES

IN CENTRAL PENNSYLVANIA

ADAMS BEDFORD COLUMBIA
CUMBERLAND DAUPHIN FRANKLIN
FULTON HUNTINGDON JUNIATA
LANCASTER LEBANON MIFFLIN
NORTHUMBERLAND PERRY SCHUYLKILL
SNYDER SOMERSET YORK

THIS INCLUDES THE CITIES OF BEDFORD, BERWICK, BLOOMSBURG,
CARLISLE, CHAMBERSBURG, GETTYSBURG, HARRISBURG, HERSHEY,
HUNTINGDON, LANCASTER, LEBANON, LEWISTOWN, MCCONNELLSBURG,
MIFFLINTOWN, MOUNT UNION, NEWPORT, POTTSVILLE, SELINSGROVE,
SHAMOKIN, SOMERSET, SUNBURY, WAYNESBORO, AND YORK.

Updated: May 20, 3:53 PM Source: NWS Alert

Hourly Air Quality Forecast - AQI (US EPA)

Pollutant Concentrations:

Health Recommendations:

Pollutant Concentrations:

Health Recommendations:

Pollutant Concentrations:

Health Recommendations:

Pollutant Concentrations:

Health Recommendations:

Weather Alerts and Warnings for Lancaster

Severe Thunderstorm Watch

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