Today | Weather | Wednesday, March 18, 2026

Active Weather Warnings

Weather in Casper, Wyoming

03:50 AM

Now

48° F

Feels Like 37°

Precipitation 7 %

Wind 18 mph

Humidity 43 %

Today

Day 79°

Night 48°

Precipitation 1 %

Wind 24 mph

UV Index (0 - 11+) 5

Warning: Strong Winds Today: 24 mph

Casper Weather Forecast Updated

29 minutes ago

Last updated on March 18, 2026 at 3:21 AM

Air Quality in Casper

NOW

37 AQI

Good air quality Dominant pollutant: O₃

Pollutant Concentrations:

PM_2.5 1.26 µg/m³

PM₁₀ 3.23 µg/m³

O₃ 0.040 ppm

NO₂ 0.4 ppb

SO₂ 0.1 ppb

CO 0.09 ppm

NH₃ 0.74 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 – 1.26 µg/m³

PM₁₀ – 3.23 µg/m³

O₃ – 78.53 µg/m³

NO₂ – 0.82 µg/m³

SO₂ – 0.36 µg/m³

CO – 99.79 µg/m³

NH₃ – 0.74 µg/m³

NO – 0 µg/m³

View Hourly Air Quality Forecast

Weather Alerts and Warnings for Casper

Severe Future Possible

Fire Weather Watch

Fire Weather Watch issued March 17 at 2:23AM MDT until March 21 at 9:00PM MDT by NWS Riverton WY

Mar 18, 12:00 PM → Mar 21, 9:00 PM

The National Weather Service in Riverton has issued a Fire Weather
Watch, which is in effect from Wednesday afternoon through
Saturday evening.

* IMPACTS: Low Humidities...Unseasonably Warm Temperatures...and
Strong Gusty Winds could cause erratic fire behavior.

* AFFECTED AREA:
In Central WY Fire Zones...280...289.
In North Central WY Fire Zone....281.

* COUNTIES AFFECTED:
In Central WY...Fremont...Natrona.
In North Central WY...Johnson.
In Southwest WY...Sweetwater.

* WIND: West 15 to 25 mph with gusts up to 40 mph. The strongest
wind is expected on Wednesday and Saturday.

* HUMIDITY: 10 to 15 percent.

* TEMPERATURES: Highs in the 70s Wednesday. Lows in 70s to around
80 Thursday through Saturday.

+ Read More

A Fire Weather Watch means that critical fire weather conditions are forecast to occur. Listen for later forecasts and possible Red Flag Warnings.

Updated: Mar 17, 12:42 PM Source: NWS Alert

Severe Expected Likely

Red Flag Warning

Red Flag Warning issued March 18 at 1:55AM MDT until March 21 at 9:00PM MDT by NWS Riverton WY

Mar 18, 12:00 PM → Mar 21, 9:00 PM

* IMPACTS: Low Humidities...Unseasonably Warm Temperatures...and
Strong Gusty Winds could cause erratic fire behavior.

* AFFECTED AREA:
In Central WY Fire Zones...280...289.
In North Central WY Fire Zone....281.

* COUNTIES AFFECTED:
In Central WY...Fremont...Natrona.
In North Central WY...Johnson.
In Southwest WY...Sweetwater.

* WIND: West 20 to 30 mph with gusts up to 45 mph today and
Saturday; 15 to 25 mph with gusts to 35 mph Thursday and Friday.

* HUMIDITY: 10 to 15 percent.

* TEMPERATURES: Highs 70 to 75 today, 75 to 80 Thursday through
Saturday.

+ Read More

A Red Flag Warning means that critical fire weather conditions are either occurring now....or will shortly. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior.

Updated: Mar 18, 3:21 AM Source: NWS Alert

Weather in Casper, Wyoming

Warning: Strong Winds Today: 24 mph

Casper Weather Forecast Updated

Air Quality in Casper

Pollutant Concentrations:

Health Recommendations:

Weather Alerts and Warnings for Casper

Fire Weather Watch

Red Flag Warning

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