Weather in Sioux City, Iowa

05:04 PM

Now

88° F

Feels Like 84°

Precipitation 0 %

Wind 22 mph

UV Index (0 - 11+) 11

Humidity 38 %

Today

Day 90°

Night 64°

Precipitation 5 %

Wind 20 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.

Sioux City Weather Forecast Updated

Last updated on October 04, 2025 3:51 PM

Air quality in Sioux City

NOW

64 AQI

Moderate air quality Dominant pollutant: O3

Pollutant Concentrations:

PM2.5 6.42 µg/m³

PM10 6.48 µg/m³

O₃ 63.08 ppb

NO₂ 1.40 ppb

SO₂ 0.66 ppb

CO 166.36 ppb

PM_2.5 – Fine particles <2.5μm

PM₁₀ – Inhalable particles <10μm

O₃ – Ozone

NO₂ – Nitrogen dioxide

SO₂ – Sulfur dioxide

CO – Carbon monoxide

Health Recommendations:

Air quality is currently in the acceptable range. However, sensitive individuals should be aware of potential risks from certain pollutants.

View Hourly Air Quality Forecast

Weather Alerts and Warnings for Sioux City

Moderate Expected Observed

Special Weather Statement

Special Weather Statement issued October 4 at 2:29AM CDT by NWS Sioux Falls SD

Oct 4, 2:29 AM → Oct 4, 8:00 PM

The combination of near record high temperatures, south winds
gusting 35 to 45 MPH, and dry crops and/or grasses will result
in elevated fire danger with dangerous burning conditions this
afternoon.

Fires will spread rapidly and show erratic behavior. Outdoor
burning is not recommended. People are urged to exercise extreme
care with respect to outdoor activities that could cause grass
or crop fires. Avoid equipment that can cause sparks. Do not toss
cigarettes on the ground. Report new fires quickly to the nearest
fire department or law enforcement office.

Updated: Oct 4, 3:51 PM Source: NWS Alert