Hourly Weather Forecast for Mount Pleasant, South Carolina

Hourly Weather | Today › Wednesday, March 18, 2026

Active Weather Warnings

Freeze Warning

Mount Pleasant, South Carolina

6 AM

36°

Feels Like 27°

Humidity: 70%

UV Index: 0

Wind: 9 mph

7 AM

36°

Feels Like 28°

Humidity: 64%

UV Index: 0

Wind: 9 mph

8 AM

36°

Feels Like 30°

Humidity: 68%

UV Index: 1

Wind: 8 mph

9 AM

37°

Feels Like 36°

Humidity: 62%

UV Index: 2

Wind: 9 mph

10 AM

43°

Feels Like 41°

Humidity: 57%

UV Index: 3

Wind: 9 mph

11 AM

46°

Feels Like 48°

Humidity: 52%

UV Index: 4

Wind: 9 mph

12 PM

52°

Feels Like 54°

Humidity: 49%

UV Index: 6

Wind: 10 mph

1 PM

54°

Feels Like 57°

Humidity: 46%

UV Index: 6

Wind: 10 mph

2 PM

55°

Feels Like 57°

Humidity: 44%

UV Index: 6

Wind: 9 mph

3 PM

55°

Feels Like 57°

Humidity: 43%

UV Index: 4

Wind: 9 mph

4 PM

57°

Feels Like 57°

Humidity: 42%

UV Index: 3

Wind: 9 mph

5 PM

55°

Feels Like 54°

Humidity: 45%

UV Index: 2

Wind: 9 mph

6 PM

55°

Feels Like 54°

Humidity: 45%

UV Index: 1

Wind: 9 mph

7 PM

54°

Feels Like 50°

Humidity: 48%

UV Index: 0

Wind: 8 mph

8 PM

52°

Feels Like 48°

Humidity: 54%

UV Index: 0

Wind: 7 mph

9 PM

48°

Feels Like 46°

Humidity: 59%

UV Index: 0

Wind: 7 mph

10 PM

46°

Feels Like 45°

Humidity: 64%

UV Index: 0

Wind: 6 mph

11 PM

46°

Feels Like 45°

Humidity: 61%

UV Index: 0

Wind: 6 mph

Hourly Air Quality Forecast - AQI (US EPA)

6 AM

66 AQI

Moderate air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 2.29 µg/m³
PM₁₀: 3.85 µg/m³
O₃: 0.059 ppm
NO₂: 0.6 ppb
SO₂: 0.6 ppb
CO: 0.13 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

7 AM

63 AQI

Moderate air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 2.22 µg/m³
PM₁₀: 3.84 µg/m³
O₃: 0.058 ppm
NO₂: 0.7 ppb
SO₂: 0.7 ppb
CO: 0.13 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

8 AM

60 AQI

Moderate air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 2.09 µg/m³
PM₁₀: 3.73 µg/m³
O₃: 0.057 ppm
NO₂: 0.7 ppb
SO₂: 0.7 ppb
CO: 0.13 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

9 AM

59 AQI

Moderate air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 1.88 µg/m³
PM₁₀: 3.54 µg/m³
O₃: 0.057 ppm
NO₂: 1.1 ppb
SO₂: 0.8 ppb
CO: 0.13 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

10 AM

59 AQI

Moderate air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 1.79 µg/m³
PM₁₀: 3.51 µg/m³
O₃: 0.057 ppm
NO₂: 1.1 ppb
SO₂: 0.8 ppb
CO: 0.13 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

11 AM

60 AQI

Moderate air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 1.81 µg/m³
PM₁₀: 3.62 µg/m³
O₃: 0.057 ppm
NO₂: 0.9 ppb
SO₂: 0.9 ppb
CO: 0.13 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

12 PM

64 AQI

Moderate air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 2.07 µg/m³
PM₁₀: 3.96 µg/m³
O₃: 0.058 ppm
NO₂: 0.8 ppb
SO₂: 0.8 ppb
CO: 0.13 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

1 PM

69 AQI

Moderate air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 2.47 µg/m³
PM₁₀: 4.41 µg/m³
O₃: 0.060 ppm
NO₂: 0.6 ppb
SO₂: 0.8 ppb
CO: 0.13 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

2 PM

74 AQI

Moderate air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 2.83 µg/m³
PM₁₀: 4.8 µg/m³
O₃: 0.062 ppm
NO₂: 0.4 ppb
SO₂: 0.7 ppb
CO: 0.13 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

3 PM

78 AQI

Moderate air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 2.97 µg/m³
PM₁₀: 4.93 µg/m³
O₃: 0.063 ppm
NO₂: 0.4 ppb
SO₂: 0.7 ppb
CO: 0.13 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

4 PM

79 AQI

Moderate air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 3 µg/m³
PM₁₀: 4.94 µg/m³
O₃: 0.063 ppm
NO₂: 0.3 ppb
SO₂: 0.7 ppb
CO: 0.13 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

5 PM

79 AQI

Moderate air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 2.89 µg/m³
PM₁₀: 4.8 µg/m³
O₃: 0.063 ppm
NO₂: 0.3 ppb
SO₂: 0.6 ppb
CO: 0.13 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

6 PM

80 AQI

Moderate air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 2.73 µg/m³
PM₁₀: 4.6 µg/m³
O₃: 0.064 ppm
NO₂: 0.4 ppb
SO₂: 0.6 ppb
CO: 0.13 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

7 PM

79 AQI

Moderate air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 2.59 µg/m³
PM₁₀: 4.43 µg/m³
O₃: 0.063 ppm
NO₂: 0.4 ppb
SO₂: 0.6 ppb
CO: 0.13 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

8 PM

78 AQI

Moderate air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 2.41 µg/m³
PM₁₀: 4.25 µg/m³
O₃: 0.063 ppm
NO₂: 0.5 ppb
SO₂: 0.6 ppb
CO: 0.13 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

9 PM

78 AQI

Moderate air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 2.32 µg/m³
PM₁₀: 4.15 µg/m³
O₃: 0.063 ppm
NO₂: 0.5 ppb
SO₂: 0.7 ppb
CO: 0.13 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

10 PM

77 AQI

Moderate air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 2.29 µg/m³
PM₁₀: 4.07 µg/m³
O₃: 0.063 ppm
NO₂: 0.5 ppb
SO₂: 0.7 ppb
CO: 0.13 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

11 PM

76 AQI

Moderate air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 2.29 µg/m³
PM₁₀: 3.98 µg/m³
O₃: 0.062 ppm
NO₂: 0.5 ppb
SO₂: 0.8 ppb
CO: 0.13 ppm

Health Recommendations:

Air quality is acceptable; some pollutants may pose a risk for a small number of unusually sensitive people.

Current Real-Time Air Quality Report

Weather Alerts and Warnings for Mount Pleasant

Moderate Expected Likely

Freeze Warning

Freeze Warning issued March 18 at 1:27AM EDT until March 18 at 10:00AM EDT by NWS Charleston SC

Mar 18, 1:27 AM → Mar 18, 10:00 AM

WHAT: Sub-freezing temperatures as low as 28 expected.

WHERE: Portions of southeast Georgia and southeast South Carolina.

WHEN: Until 10 AM EDT this morning.

IMPACTS: Frost and freeze conditions could kill crops, other
sensitive vegetation and possibly damage unprotected outdoor
plumbing.

+ Read More

Take steps now to protect tender plants from the cold.

Updated: Mar 18, 5:50 AM Source: NWS Alert

Hourly Air Quality Forecast - AQI (US EPA)

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Weather Alerts and Warnings for Mount Pleasant

Freeze Warning

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