St Louis Weather Conditions and Forecast, December 21, 2017

St Louis Weather Conditions & Forecast, December 21, 2017

St Louis Weather Conditions, Forecast & Air Quality Index readings published by STL.News

ST LOUIS, MO/December 21, 2017 (STL.News) St Louis weather conditions & forecast readings from the St. Louis Lambert International Airport at 4:51 a.m at Latitude: 38.75°N, Longitude: 90.37°W – Elevation 604 feet.  Forecast is provided by the National Weather Service (N.W.S.).

Current Weather Conditions


Temperature: 33°F – 1°C
Humidity: 66%
Wind Speed: E 7 mph
Barometer: 29.96 in (1015.0 MB)
Dew-point: 23°F – -5°C
Visibility: 10 Miles
Wind Chill: 27°F – -3°C
Heat Index: N/A°F – N/A°C

Extended Weather Forecast for the St Louis, Missouri area beginning December 21, 2017

Today: Cloudy – high near 55 with south wind 6 to 9 mph.
Tonight: Chance of drizzle early pm, cloudy – low around 42 with southeast wind 5 to 7 mph.
Friday: 20 percent chance of rain in the pm, cloudy – high near 46 with northwest wind 5 to 7 mph.
Friday Night: Chance of rain before 3 am followed by a chance of rain/snow between early am, then a chance of snow after 5 am, cloudy – low around 32 with northwest wind 5 to 7 mph and a chance of precipitation – 40%.
Saturday: 20 percent chance of snow in the am, partly sunny – high near 39.
Saturday Night: Mostly cloudy – low around 23.
Sunday: 30 percent chance of snow in the pm, mostly sunny – high near 33.
Sunday Night: Partly cloudy – low around 23.
Christmas Day: Mostly sunny – high near 36.
Monday Night: Mostly cloudy – low around 22.
Tuesday: Partly sunny – high near 34.
Tuesday Night: Mostly cloudy – low around 20.
Wednesday: 20 percent chance of snow, partly sunny – high near 34.

Air Quality Index for Saint Louis, Missouri – (A.Q.I.)

Delayed Air Quality Index: 12/20/17 3:00 PM CST

  • Good – 20 AQI – Ozone
  • Good – 13 AQI – Particle Pollution (2.5 microns)
  • Good – 10 AQI – Particle Pollution (10 microns)

Agency: St. Louis Metropolitan Area (American Lung Association)

Air Quality Index (A.Q.I.)

Good – Air quality in considered “satisfactory” and air pollution poses little to no threat.

Moderate – Air quality is considered “acceptable.” However, some pollutants there may be a moderate health concern for a very small number of people who are sensitive to air pollution.

USG – while the general public will not likely be affected by this AQI range, people with lung disease, older adults and children are a great risk from exposure to ozone, whereas, persons with heart and lung disease, old adults and children are at greater risk from the presence of particles in the air.

Unhealthy – Everyone may begin to experience health effects members of sensitive groups may experience more serious health effects.

Very Unhealthy – Health Alert: everyone may experience more serious health effects.


Source: Current Weather Conditions and Forecast are obtained from the National Weather Service @ Forecast.Weather.Gov – Air Quality Index (AQI) readings are obtained from AirNow.Gov – (MS)


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