NWS Riverton WY - Winter Weather

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Winter Weather Safety

Each year, as many as two dozen major snow storms occur between Wyoming's borders, bringing heavy snow to parts of the state. But snow is only one of the dangers that affect the state each winter. Gale force winds and sub freezing temperatures can also wreak havoc at almost any time between October and April.

While relatively few people are directly killed by severe winter storms, and untold higher number of fatalities can often be indirectly attributed to winter weather. Some examples of the indirect dangers of winter are:

Traffic accidents on icy roads.
-about 70% of winter deaths related to ice and snow occur in automobiles.
-Prepare your vehicle
Heart Attacks after shoveling heavy snow
-Safer snow shoveling
Frostbite and Hypothermia
-50% of people that die from exposure to cold are over 60 years old. 20% of the deaths occur in the home.
Avalanches
Carbon Monoxide poisoning
House fires caused by space heaters and fireplaces

Generations of hardy people have survived Wyoming's winters, and generations more will in the years to come. Learning about the dangers that come with each winter, and how to prepare for them, will help you to join that group. Click here to view a helpful guide (.pdf) from the Wyoming Office of Homeland Security Emergency Management Agency.

Winter Weather Terminology

The National Weather Service uses specific terminology to describe winter weather events. Understanding the definitions is important, so that you know what to do during different circumstances. Remember these terms, because the next time you hear them, your life and the lives of others may depend upon it!

Winter Storm Watch - severe winter weather may affect your area within 48 hours. You still have time to prepare.

Blizzard Warning - the most dangerous of all winter weather is occurring or imminent: If you are caught outdoors or on the road, you could lose your life! A blizzard is defined as a combination of winds 35 mph or greater with snow or blowing snow reducing visibility to less than 1/4 mile for three or more hours. In blizzards, white-out conditions, deep snow drifts, and frigid wind chills form a life-threatening partnership. You should seek refuge immediately!

Winter Storm Warning - severe winter weather is occurring or imminent. You should already be prepared and should take protective actions immediately.

- issued when the following amounts of snow are expected:

At lower elevations (below 7500 feet) - 6 inches or more in 24 hours or an event.
In the mountains (above 7500 feet) - 12 inches or more in 24 hours or an event.

Travel can become difficult or impossible, especially for vehicles without four-wheel drive.

High Wind Warning - hazardous winds are occurring or will soon occur across a significant area.

For elevations below 7500 feet - sustained winds of 40 mph or greater or gusts to 60 mph or more.
In higher elevations - sustained winds of 50 mph or greater or gusts to at least 75 mph.
Travel can be downright dangerous, especially for high profile vehicles like semi trucks, buses, and vans.

Wind Chill Warning

Wind Chill Chart / What is the wind chill factor?

- wind chill is the combined effect of cold temperatures and wind in chilling the body. A Warning is issued when wind chills of minus 40 degrees F or colder, with winds of at least 10 mph, are occurring or imminent. Frostbite can occur in seconds, and hypothermia within minutes!

Snow Advisory - weather conditions are expected to cause significant inconveniences and may be hazardous, especially to motorists. If caution is exercised, however, these situations should not become life threatening. Examples of conditions for which advisories are issued include snow, blowing snow, frost, freezing drizzle, and dangerous wind chill.

- issued when the following amounts of snow are expected:

At lower elevations (below 7500 feet) - 3-6 inches in 24 hours or an event.
In the mountains (above 7500 feet) - 5-12 inches in 24 hours or an event.

Latest NWS Riverton
Warnings, Watches, Advisories, & Statements

Winter Weatherr / Heavy Snow	Non-Precipitation Statement
Special Weather Statement	Hazardous Weather Outlook

National Winter Weather Discussions and Information

Watches, Warnings & Advisories	Heavy Snow Discussion
Heavy Snow Outlook (6-18 hr)	Heavy Snow Outlook (18-30 hr)
Heavy Snow Outlook (Day 2)	Interpreting Outlook Maps

Other Snow Information

Road Conditions	Wyoming SNOTEL Sites
Winter Storm Safety	General Snow Information

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