A blizzard is a specific kind of severe snowstorm defined mainly by wind and very poor visibility, not just by how much snow falls.

Core definition

  • Meteorologists define a blizzard as a storm with:
    • Strong winds of at least about 35 mph (56 km/h).
* Blowing or falling snow that cuts visibility to a quarter mile (about 400 m) or less.

* These conditions lasting at least 3 hours.
  • The difference between a regular snowstorm and a blizzard is mainly wind speed and the resulting whiteout conditions.

What actually “makes” a blizzard?

Several ingredients have to come together in the atmosphere:

  • Cold air: Temperatures must be low enough for precipitation to fall or exist as snow.
  • Moisture: Air masses bringing moisture (for example from oceans or large lakes) provide the snow.
  • Lift and low pressure: Strong low‑pressure systems force moist air to rise, cool, and produce widespread snow.
  • Strong pressure gradient: A big contrast between high and low pressure areas creates the intense winds that turn a snowstorm into a blizzard.

Regional twists

  • In the United States, the official criteria are ≥35 mph winds, visibility ≤0.25 mile, lasting at least 3 hours.
  • Environment Canada uses similar visibility criteria, with winds over 40 km/h and duration of at least 4–6 hours depending on region.
  • Australia’s weather service emphasizes “violent and very cold wind” loaded with snow, including snow lifted from the ground.

What it feels like in a blizzard

  • People in blizzards often report near‑total whiteout, where all you can see is swirling white and faint, shifting shapes.
  • The combination of bitter wind, blowing snow, and low visibility makes travel dangerous and can paralyze whole regions for days.

TL;DR: What makes a blizzard is not just heavy snow, but strong, sustained winds plus blowing snow that crushes visibility to near zero for several hours.

Information gathered from public forums or data available on the internet and portrayed here.