Today | Weather | Monday, July 20, 2026

Active Weather Warnings

Heat Advisory

Weather in Rapid City, South Dakota

03:28 PM

Now

95° F

Feels Like 99°

Precipitation 34 %

Wind 9 mph

UV Index (0 - 11+) 7

Humidity 23 %

Today

Day 97°

Night 64°

Precipitation 87 %

Wind 10 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.

Rapid City Weather Forecast Updated

20 minutes ago

Last updated on July 20, 2026 at 3:08 PM

Air Quality in Rapid City

NOW

44 AQI

Good air quality Dominant pollutant: O₃

Pollutant Concentrations:

PM_2.5 5.05 µg/m³

PM₁₀ 6.33 µg/m³

O₃ 0.047 ppm

NO₂ 0.1 ppb

SO₂ 0.2 ppb

CO 0.08 ppm

NH₃ 1.8 µg/m³

NO 0.04 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 – 5.05 µg/m³

PM₁₀ – 6.33 µg/m³

O₃ – 93.1 µg/m³

NO₂ – 0.25 µg/m³

SO₂ – 0.49 µg/m³

CO – 87.59 µg/m³

NH₃ – 1.8 µg/m³

NO – 0.04 µg/m³

View Hourly Air Quality Forecast

Weather Alerts and Warnings for Rapid City

Moderate Expected Likely

Heat Advisory

Heat Advisory issued July 20 at 1:50PM MDT until July 20 at 9:00PM MDT by NWS Rapid City SD

Jul 20, 1:50 PM → Jul 20, 9:00 PM

WHAT: Heat index values up to 100.

WHERE: Portions of northwestern, south central, and southwestern
South Dakota and northeast Wyoming.

WHEN: Until 9 PM MDT /10 PM CDT/ this evening.

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

+ Read More

Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors.

Updated: Jul 20, 3:08 PM Source: NWS Alert