Today | Weather | Wednesday, June 17, 2026

Active Weather Warnings

Wind Advisory

Weather in St. Louis, Missouri

04:14 AM

Now

63° F

Feels Like 63°

Precipitation 1 %

Wind 6 mph

Humidity 83 %

Today

Day 93°

Night 70°

Precipitation 55 %

Wind 15 mph

UV Index (0 - 11+) 11

Warning: Extreme UV Index Today: 11

Overexposure to the sun's harmful UV rays can cause sunburn and increase the risk of developing skin cancer, including melanoma. Protect yourself by wearing clothing that covers your skin, sunglasses, and a hat. Apply a broad-spectrum sunscreen with an SPF of 30 or higher every two hours, even on cloudy days. Minimize direct sun exposure during peak hours (10 AM to 4 PM) to reduce the risk.

St. Louis Weather Forecast Updated

8 minutes ago

Last updated on June 17, 2026 at 4:06 AM

Weather Forecast History

Last Year's Weather on This Day (June 17, 2025)

Day

91°

Night

73°

Wind

4 mph

UV Index

Precipitation

25 %

Air Quality in St. Louis

NOW

17 AQI

Good air quality Dominant pollutant: O₃

Pollutant Concentrations:

PM_2.5 1.87 µg/m³

PM₁₀ 1.99 µg/m³

O₃ 0.019 ppm

NO₂ 0.4 ppb

SO₂ 0 ppb

CO 0.08 ppm

NH₃ 0.38 µg/m³

NO 0 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 – 1.87 µg/m³

PM₁₀ – 1.99 µg/m³

O₃ – 36.43 µg/m³

NO₂ – 0.66 µg/m³

SO₂ – 0.06 µg/m³

CO – 92.08 µg/m³

NH₃ – 0.38 µg/m³

NO – 0 µg/m³

View Hourly Air Quality Forecast

Weather Alerts and Warnings for St. Louis

Moderate Expected Likely

Wind Advisory

Wind Advisory issued June 17 at 2:26AM CDT until June 17 at 8:00PM CDT by NWS St Louis MO

Jun 17, 1:00 PM → Jun 17, 8:00 PM

WHAT: Southwest winds 20 to 30 mph with gusts up to 45 mph
expected.

WHERE: Portions of south central and southwest Illinois and east
central Missouri.

WHEN: From 1 PM this afternoon to 8 PM CDT this evening.

IMPACTS: Gusty winds will blow around unsecured objects. Tree
limbs could be blown down and a few power outages may result.

+ Read More

Winds this strong can make driving difficult, especially for high profile vehicles. Use extra caution. Secure outdoor objects.

Updated: Jun 17, 4:06 AM Source: NWS Alert