Hourly Weather Forecast for St. Joseph, Missouri

Hourly Weather | Today › Tuesday, September 1, 2026

Active Weather Warnings

Heat Advisory

St. Joseph, Missouri

11 AM

88°

Feels Like 93°

Humidity: 49%

UV Index: 5

Wind: 10 mph

12 PM

91°

Feels Like 97°

Humidity: 43%

UV Index: 6

Wind: 12 mph

1 PM

95°

Feels Like 99°

Humidity: 39%

UV Index: 7

Wind: 12 mph

2 PM

97°

Feels Like 99°

Humidity: 36%

UV Index: 6

Wind: 12 mph

3 PM

97°

Feels Like 99°

Humidity: 33%

UV Index: 5

Wind: 12 mph

4 PM

99°

Feels Like 99°

Humidity: 32%

UV Index: 4

Wind: 12 mph

5 PM

97°

Feels Like 97°

Humidity: 34%

UV Index: 2

Wind: 12 mph

6 PM

95°

Feels Like 95°

Humidity: 37%

UV Index: 1

Wind: 10 mph

7 PM

91°

Feels Like 91°

Humidity: 43%

UV Index: 0

Wind: 9 mph

8 PM

88°

Feels Like 88°

Humidity: 51%

UV Index: 0

Wind: 8 mph

9 PM

82°

Feels Like 82°

Humidity: 57%

UV Index: 0

Wind: 7 mph

10 PM

79°

Feels Like 81°

Humidity: 65%

UV Index: 0

Wind: 7 mph

11 PM

75°

Feels Like 75°

Humidity: 74%

UV Index: 0

Wind: 7 mph

Hourly Air Quality Forecast - AQI (US EPA)

11 AM

43 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 5.7 µg/m³
PM₁₀: 6.22 µg/m³
O₃: 0.046 ppm
NO₂: 0.9 ppb
SO₂: 0.6 ppb
CO: 0.10 ppm

Health Recommendations:

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

12 PM

47 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 6.24 µg/m³
PM₁₀: 6.76 µg/m³
O₃: 0.051 ppm
NO₂: 0.6 ppb
SO₂: 0.6 ppb
CO: 0.10 ppm

Health Recommendations:

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

1 PM

49 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 6.74 µg/m³
PM₁₀: 7.25 µg/m³
O₃: 0.053 ppm
NO₂: 0.5 ppb
SO₂: 0.7 ppb
CO: 0.10 ppm

Health Recommendations:

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

2 PM

54 AQI

Moderate air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 5.18 µg/m³
PM₁₀: 5.62 µg/m³
O₃: 0.055 ppm
NO₂: 0.3 ppb
SO₂: 0.5 ppb
CO: 0.09 ppm

Health Recommendations:

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

3 PM

57 AQI

Moderate air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 4.43 µg/m³
PM₁₀: 4.82 µg/m³
O₃: 0.056 ppm
NO₂: 0.3 ppb
SO₂: 0.3 ppb
CO: 0.08 ppm

Health Recommendations:

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

4 PM

59 AQI

Moderate air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 4.5 µg/m³
PM₁₀: 4.87 µg/m³
O₃: 0.057 ppm
NO₂: 0.3 ppb
SO₂: 0.3 ppb
CO: 0.08 ppm

Health Recommendations:

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

5 PM

60 AQI

Moderate air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 4.76 µg/m³
PM₁₀: 5.13 µg/m³
O₃: 0.057 ppm
NO₂: 0.4 ppb
SO₂: 0.4 ppb
CO: 0.08 ppm

Health Recommendations:

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

6 PM

58 AQI

Moderate air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 5.09 µg/m³
PM₁₀: 5.45 µg/m³
O₃: 0.057 ppm
NO₂: 0.5 ppb
SO₂: 0.4 ppb
CO: 0.09 ppm

Health Recommendations:

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

7 PM

55 AQI

Moderate air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 5.39 µg/m³
PM₁₀: 5.76 µg/m³
O₃: 0.056 ppm
NO₂: 0.7 ppb
SO₂: 0.4 ppb
CO: 0.09 ppm

Health Recommendations:

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

8 PM

50 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 5.7 µg/m³
PM₁₀: 6.08 µg/m³
O₃: 0.054 ppm
NO₂: 0.8 ppb
SO₂: 0.4 ppb
CO: 0.09 ppm

Health Recommendations:

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

9 PM

49 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 6.08 µg/m³
PM₁₀: 6.47 µg/m³
O₃: 0.053 ppm
NO₂: 0.8 ppb
SO₂: 0.4 ppb
CO: 0.09 ppm

Health Recommendations:

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

10 PM

48 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 6.5 µg/m³
PM₁₀: 6.9 µg/m³
O₃: 0.052 ppm
NO₂: 0.9 ppb
SO₂: 0.5 ppb
CO: 0.09 ppm

Health Recommendations:

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

11 PM

47 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 6.83 µg/m³
PM₁₀: 7.25 µg/m³
O₃: 0.051 ppm
NO₂: 0.9 ppb
SO₂: 0.6 ppb
CO: 0.09 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 St. Joseph

Moderate Expected Likely

Heat Advisory

Heat Advisory issued September 1 at 4:03AM CDT until September 4 at 8:00PM CDT by NWS Kansas City/Pleasant Hill MO

Sep 1, 4:03 AM → Sep 4, 8:00 PM

WHAT: Heat index values up to 105.

WHERE: Portions of east central and northeast Kansas and central,
north central, northeast, northwest, and west central Missouri.

WHEN: Until 8 PM CDT Friday.

IMPACTS: Hot temperatures and high humidity may cause heat
illnesses.

ADDITIONAL DETAILS: While heat index values may not reach 105 each
day, the combination of the longevity of the heat and little or
limited relief during overnight periods have prompted the multi-day
Heat Advisory.

+ Read More

Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors. Take extra precautions when outside. Wear lightweight and loose fitting clothing. Try to limit strenuous activities to early morning or evening. Take action when you see symptoms of heat exhaustion and heat stroke.

Updated: Sep 1, 10:00 AM Source: NWS Alert

Hourly Air Quality Forecast - AQI (US EPA)

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Weather Alerts and Warnings for St. Joseph

Heat Advisory

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