Name: St. Louis
Address: MO, US

Official alert

Extreme Heat Watch

* WHAT...Dangerously hot conditions with heat index values of 102 to 108 degrees, and morning lows from 75 to 80 degrees, possible for several consecutive days.

Affects Clinton; Washington; Randolph; Madison; St. Clair; Monroe; St. Charles; St. Louis; St. Louis City

Read the full guidance

What is happening

* WHAT...Dangerously hot conditions with heat index values of 102 to 108 degrees, and morning lows from 75 to 80 degrees, possible for several consecutive days. * WHERE...In Illinois, Clinton IL, Washington IL, Madison IL, Monroe IL, Randolph IL, and Saint Clair IL Counties. In Missouri, Saint Charles MO, Saint Louis City MO, and Saint Louis MO Counties. * WHEN...From Monday afternoon through Friday evening. * IMPACTS...Heat related illnesses increase significantly during extreme heat and high humidity events. * ADDITIONAL DETAILS...In addition to near-record afternoon temperatures, warm morning lows may provide little relief, especially Wednesday through Friday.

What the National Weather Service recommends

Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors. Monitor the latest forecasts and warnings for updates.

View this alert on weather.gov

St. Louis smoke check

A little smoke up high. The air down here is so-so.

There’s smoke up high, while the air reading below shows what’s happening closer to home.

Updated Sun, Aug 30, 12:36 PM · St. Louis, MO-IL

Smoke in the skyLight smokeLast sky check · Aug 30

Air near youAQI 58Moderate · fine particles

Smoke in motion

See what the smoke is doing.

Watch recent smoke move across St. Louis. Satellite imagery shows what’s overhead, while today’s air reading shows what’s happening closer to the ground. Tap or click the map to pause or play; pinch to zoom.

Loading the latest smoke and fire view…

A peek ahead

How the air may change

The air forecast stays fairly steady and stays moderate through this view.

Any fires nearby?

No current mapped wildfire perimeters showed up within 100 miles. Smoke can still wander in from farther away.

12 PM58fine particles

Complete city forecast

See the full St. Louis forecast

Current weather · next 24 hours · five days · radar

Plan around it

Find your best time in St. Louis.

Pick an activity and we’ll check the conditions.

What do you want to do?

Fine-tune this plan Optional

How long will you be outside?1 hr

How far ahead should we look?The next 3 days

What times work for you?6:00 AM–9:00 PM

Earliest start

Finished by

The full activity must fit between these times.

What should we be extra careful about? Optional

Air quality or smokeSun or UVHeatCold

How we knowSources, updates, and important limits

Different instruments. One honest answer.

We check the sky and the air near the ground separately, because smoke up high does not always reach the people below.

Refresh rhythm: Air and weather check in throughout the day. The smoke map gets a fresh look when NOAA posts one.
Important limit: Smoke can change from one neighborhood to the next, so this check cannot describe every corner of the St. Louis, MO-IL.
Sources used here: NOAA Hazard Mapping System · satellite-observed smoke · AirNow · participating air agencies · US AQI · National Weather Service · hourly weather and alerts · NIFC WFIGS · current interagency fire perimeters

Read the full source methodology Understand this signal