Today | Weather | Wednesday, May 20, 2026

Active Weather Warnings

Flood Warning

Weather in St. Joseph, Missouri

04:51 PM

Now

66° F

Feels Like 66°

Precipitation 0 %

Wind 10 mph

UV Index (0 - 11+) 3

Humidity 46 %

Today

Day 66°

Night 54°

Precipitation 1 %

Wind 9 mph

UV Index (0 - 11+) 10

Warning: High UV Index Today: 10

High risk of harm from unprotected sun exposure. Take precautions: wear a hat, sunglasses, and apply sunscreen regularly if you’ll be outdoors for extended periods.

St. Joseph Weather Forecast Updated

Last updated on May 20, 2026 at 3:33 PM

Air Quality in St. Joseph

NOW

43 AQI

Good air quality Dominant pollutant: O₃

Pollutant Concentrations:

PM_2.5 2.23 µg/m³

PM₁₀ 2.42 µg/m³

O₃ 0.046 ppm

NO₂ 0.5 ppb

SO₂ 0.6 ppb

CO 0.10 ppm

NH₃ 2.47 µg/m³

NO 0.16 µg/m³

PM_2.5 – Fine particles <2.5μm

PM₁₀ – Inhalable particles <10μm

O₃ – Ozone

NO₂ – Nitrogen dioxide

SO₂ – Sulfur dioxide

CO – Carbon monoxide

NH₃ – Ammonia

NO – Nitric oxide

Health Recommendations:

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

Show raw pollutant concentrations (µg/m³)

PM_2.5 – 2.23 µg/m³

PM₁₀ – 2.42 µg/m³

O₃ – 91.04 µg/m³

NO₂ – 0.86 µg/m³

SO₂ – 1.54 µg/m³

CO – 117.11 µg/m³

NH₃ – 2.47 µg/m³

NO – 0.16 µg/m³

View Hourly Air Quality Forecast

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