Hourly Weather Forecast for St. Joseph, Missouri

Hourly Weather | Today › Wednesday, May 20, 2026

Active Weather Warnings

Flood Warning

St. Joseph, Missouri

6 PM

66°

Feels Like 66°

Humidity: 42%

UV Index: 2

Wind: 10 mph

7 PM

64°

Feels Like 64°

Humidity: 46%

UV Index: 1

Wind: 10 mph

8 PM

63°

Feels Like 61°

Humidity: 53%

UV Index: 0

Wind: 8 mph

9 PM

61°

Feels Like 57°

Humidity: 59%

UV Index: 0

Wind: 7 mph

10 PM

59°

Feels Like 57°

Humidity: 65%

UV Index: 0

Wind: 6 mph

11 PM

57°

Feels Like 55°

Humidity: 71%

UV Index: 0

Wind: 6 mph

Hourly Air Quality Forecast - AQI (US EPA)

6 PM

43 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 2.23 µg/m³
PM₁₀: 2.42 µg/m³
O₃: 0.046 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.

7 PM

42 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 2.15 µg/m³
PM₁₀: 2.36 µg/m³
O₃: 0.045 ppm
NO₂: 0.8 ppb
SO₂: 0.6 ppb
CO: 0.10 ppm

Health Recommendations:

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

8 PM

40 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 2.02 µg/m³
PM₁₀: 2.24 µg/m³
O₃: 0.043 ppm
NO₂: 1.2 ppb
SO₂: 0.6 ppb
CO: 0.11 ppm

Health Recommendations:

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

9 PM

37 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 1.92 µg/m³
PM₁₀: 2.17 µg/m³
O₃: 0.040 ppm
NO₂: 1.5 ppb
SO₂: 0.6 ppb
CO: 0.11 ppm

Health Recommendations:

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

10 PM

35 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 1.86 µg/m³
PM₁₀: 2.13 µg/m³
O₃: 0.038 ppm
NO₂: 1.8 ppb
SO₂: 0.6 ppb
CO: 0.11 ppm

Health Recommendations:

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

11 PM

33 AQI

Good air quality Dominant pollutant: O₃

Details

Pollutant Concentrations:

PM_2.5: 1.81 µg/m³
PM₁₀: 2.1 µg/m³
O₃: 0.036 ppm
NO₂: 1.9 ppb
SO₂: 0.6 ppb
CO: 0.11 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

Severe Immediate Observed

Flood Warning

Flood Warning issued May 19 at 8:33PM CDT until May 21 at 6:24AM CDT by NWS Kansas City/Pleasant Hill MO

May 19, 8:33 PM → May 21, 6:24 AM

...The Flood Warning continues for the following rivers in Kansas...
Missouri...

Missouri River at St Joseph affecting Andrew, Buchanan and Doniphan
Counties.

WHAT: Minor flooding is occurring and minor flooding is forecast.

WHERE: Missouri River at St Joseph.

WHEN: Until Thursday morning.

IMPACTS: At 19.0 feet, Backwater from the Missouri River floods
property along the Nodaway river at Nodaway, Missouri.

ADDITIONAL DETAILS:
- At 8:00 PM CDT Tuesday the stage was 18.7 feet.
- Forecast...The river is expected to rise to a crest of 18.8 feet
just after midnight tonight. It will then fall below flood stage
tomorrow morning.
- Flood stage is 17.0 feet.
- http://www.weather.gov/safety/flood

+ Read More

Turn around, don't drown when encountering flooded roads. Most flood deaths occur in vehicles. Motorists should not attempt to drive around barricades or drive cars through flooded areas. This product along with additional weather and stream information is available at www.weather.gov/kc/.

Updated: May 20, 4:51 AM Source: NWS Alert

Hourly Air Quality Forecast - AQI (US EPA)

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Weather Alerts and Warnings for St. Joseph

Flood Warning

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