Strange Weather Phenomena • Winter Weather • Snowstorms
A blizzard is not simply a large pile of snow. It is what happens when wind weaponizes that snow and erases the visible world.
What qualifies as a blizzard? How is it different from a major snowstorm, nor’easter, bomb cyclone or lake-effect snow event? This guide explains official blizzard criteria, snowstorm formation, whiteouts, blowing and drifting snow, ground blizzards, snowfall intensity, snow loading, regional blizzard patterns, forecasting challenges, historic storm types, dangerous impacts and winter-storm safety.
Published:
Updated:
Scope:
This specialist pillar focuses on snow-dominated storms and blizzard conditions. For the broader system of snow, ice and winter cyclones, begin with
Winter Weather Explained.
Dedicated guides cover
Lake-Effect Snow,
Ice Storms,
Nor’easters
and
Bomb Cyclones.
Blizzards and major snowstorms are related but not identical. A major snowstorm is defined mainly by disruptive snowfall and its impacts. A blizzard is defined by the combination of strong wind, falling or blowing snow, severely reduced visibility and sustained duration. One storm may be both. Another may bury a city under record snow without meeting strict blizzard criteria. A third may produce a ground blizzard after the snow has already stopped falling.
Blizzards and Major Snowstorms: Quick Facts
- A blizzard is fundamentally a wind-and-visibility hazard.
- Common U.S. criteria include winds or frequent gusts of at least 35 mph, visibility of one-quarter mile or less and conditions lasting at least three hours.
- Operational definitions and thresholds may differ between countries and forecast authorities.
- A blizzard does not require a specific snowfall total.
- A major snowstorm can produce extreme accumulation without becoming a blizzard.
- Blowing snow may come from falling snow, loose snow already on the ground or both.
- A ground blizzard can occur after precipitation ends.
- A whiteout describes severe visibility and contrast loss; it is not automatically a blizzard.
- Wet snow creates heavier loads on roofs, trees and power lines.
- Dry powder is more easily transported by wind and can create severe drifting.
- Snowdrifts may become much deeper than the official snowfall total.
- Snowfall rate can matter more than the final accumulation during travel hours.
- Thunder and lightning can occur during intense snowstorms, but thundersnow does not define a blizzard.
- A nor’easter can produce a blizzard, but the terms describe different aspects of the storm.
- A bomb cyclone can produce blizzard conditions, but rapid deepening alone does not make it a blizzard.
- Lake-effect snow may produce local blizzard conditions, but its formation mechanism belongs in a separate pillar.
- Major snowstorms are especially dangerous when wind, extreme cold, mobility failure and prolonged power loss overlap.
What Is a Blizzard?
A blizzard is a severe winter-weather event in which strong winds combine with falling snow, blowing snow or both to reduce visibility to extremely low levels for a sustained period.
The defining hazard is not snow depth. It is the combination of:
- strong wind;
- airborne snow;
- severely restricted visibility;
- prolonged duration.
Blizzard conditions can make travel impossible, disorient people within meters of shelter, create rapidly growing snowdrifts and prevent emergency services from reaching stranded communities.
Blizzard Criteria and Regional Definitions
Blizzard criteria are operational definitions used by meteorological agencies. They may differ by country.
Common United States criteria
The U.S. National Weather Service commonly defines a blizzard using:
- Wind: Sustained wind or frequent gusts of at least 35 mph, approximately 56 km/h.
- Visibility: One-quarter mile, approximately 400 meters, or less.
- Snow: Falling snow, blowing snow or both.
- Duration: Conditions expected to persist for at least three hours.
These criteria are useful for explaining U.S. events, but they should not be presented as the only possible global definition.
Why definitions vary
National and regional agencies may use different:
- wind thresholds;
- visibility thresholds;
- duration requirements;
- warning terminology;
- local hazard criteria;
- standards for open terrain, coastal regions or populated areas.
Some countries use broader terms such as severe snowstorm, blowing-snow warning or winter-storm warning rather than relying on a single universal blizzard threshold.
What Is a Major Snowstorm?
Major snowstorm is a broader practical term for a snow-producing weather system that causes substantial disruption.
A major snowstorm may involve:
- very heavy snowfall;
- rapid accumulation;
- long storm duration;
- strong winds;
- drifting snow;
- mixed precipitation;
- record or near-record snow totals;
- large transportation impacts;
- widespread closures;
- power outages;
- roof and tree damage;
- dangerous cold before or after the storm.
Unlike blizzard, “major snowstorm” usually does not have one universal meteorological threshold. Its meaning depends on accumulation, impacts and local climatology.
Why local context matters
Twenty centimeters of snow may be manageable in a well-equipped snowbelt city but crippling in a region where:
- heavy snow is rare;
- drivers lack winter experience;
- vehicles use unsuitable tires;
- snow-removal resources are limited;
- buildings are not designed for snow loads;
- vegetation remains in leaf;
- airports and roads lack deicing capacity.
Blizzard vs Snowstorm vs Winter Storm
| Term | What defines it | Snow required? | Main hazards |
|---|---|---|---|
| Winter storm | An umbrella term for hazardous cold-season precipitation and wind | Not always | Snow, sleet, freezing rain, wind and ice |
| Snowstorm | Falling snow and accumulation | Yes | Accumulation, reduced visibility and travel disruption |
| Major snowstorm | High-impact or unusually extensive snow event | Yes | Heavy snow, closures, structural loading and widespread disruption |
| Blizzard | Wind, airborne snow, extremely low visibility and sustained duration | Falling or previously accumulated snow | Whiteout, drifting, exposure and mobility collapse |
| Ground blizzard | Wind lifting existing loose snow after or without new snowfall | No new snow required | Whiteout, drifts and road closures |
How Blizzards and Major Snowstorms Form
Most large snowstorms require several atmospheric ingredients to overlap in the correct place and at the correct time.
- Cold air must occupy enough of the atmospheric column for snow to survive to the surface.
- Moisture must enter the storm from an ocean, sea, lake or other source.
- Lift must force moist air upward, allowing clouds and precipitation to develop.
- A weather disturbance must organize snowfall and circulation.
- A pressure gradient must become strong enough to generate damaging wind or blowing snow.
- Storm duration must be sufficient for major accumulation or prolonged blizzard conditions.
Common lifting mechanisms
- warm fronts;
- cold fronts;
- occluded fronts;
- upper-level troughs;
- jet-stream divergence;
- low-pressure circulation;
- mountain uplift;
- convergence between air masses;
- mesoscale deformation zones.
Moisture sources
- Atlantic Ocean;
- Pacific Ocean;
- Gulf of Mexico;
- Mediterranean Sea;
- North Sea;
- Sea of Japan;
- large unfrozen lakes;
- atmospheric rivers.
How Snow Forms Inside a Major Winter Storm
Snow crystals develop in clouds when water vapor deposits onto microscopic ice-forming particles.
The crystals grow through:
- vapor deposition;
- collision with supercooled droplets;
- aggregation with other crystals;
- movement through cloud layers with favorable temperature and humidity.
The most efficient snow-crystal growth often occurs within a temperature layer favorable for branching dendrites. Strong upward motion through this layer can produce large flakes and very high snowfall rates.
Snowfall can intensify when:
- moisture is deep;
- air rises rapidly;
- the crystal-growth zone is saturated;
- the storm becomes dynamically stronger;
- fronts or deformation zones remain nearly stationary;
- terrain forces additional ascent;
- convective instability develops.
Wet Snow, Powder Snow and Snowfall Ratios
Snow depth is not determined solely by the amount of water falling from the sky.
Meteorologists use the snow-to-liquid ratio to compare snow depth with the liquid water contained in it.
Wet snow
Wet snow usually forms near the freezing point.
- It is dense and sticky.
- It adheres to trees and wires.
- It creates high structural loads.
- It compacts quickly.
- It is difficult to shovel.
- It is less easily blown than dry powder.
Dry powder
Dry snow generally forms in colder air.
- It is lighter and fluffier.
- It may produce greater snow depth from the same liquid amount.
- It is easily lifted by wind.
- It produces severe drifting.
- It can create ground blizzards long after snowfall stops.
Why ratios vary
- temperature through the cloud;
- crystal shape;
- wind fragmentation;
- surface temperature;
- compaction;
- partial melting;
- mixed precipitation.
Heavy Snow Bands and Deformation Zones
The heaviest snowfall within a large storm often occurs in narrow bands rather than across the entire precipitation shield.
Snow bands can develop through:
- frontogenesis;
- deformation around a deepening cyclone;
- conditional instability;
- terrain enhancement;
- lake or sea enhancement;
- persistent convergence.
Locations beneath a band may receive snowfall rates several times greater than nearby areas.
Why band placement matters
- A shift of 30–50 kilometers can change totals dramatically.
- Visibility can collapse within minutes.
- Road crews may be overwhelmed despite manageable regional averages.
- Localized “jackpot” totals can make an otherwise accurate forecast appear wrong.
Lake-effect bands are explained separately because their energy source and spatial behavior differ from the main synoptic snow shield.
Why Blizzard Winds Become So Strong
Strong blizzard winds are commonly associated with a tight pressure gradient around an intense low-pressure system.
Wind strengthens when:
- central pressure falls;
- high pressure remains nearby;
- the pressure gradient tightens;
- cold air surges behind the storm;
- strong winds aloft mix toward the surface;
- open terrain provides little friction;
- mountain gaps or valleys channel airflow;
- the cyclone intensifies rapidly.
Strong wind affects more than visibility. It also:
- redistributes snow;
- creates deep drifts;
- exposes some surfaces while burying others;
- increases wind chill;
- damages trees and infrastructure;
- makes plowing less effective;
- causes repeated road closures after clearing.
Whiteouts and Visibility Collapse
A whiteout occurs when airborne snow and diffuse light eliminate visual contrast.
During a severe whiteout:
- the horizon disappears;
- road edges become impossible to distinguish;
- terrain features lose contrast;
- nearby objects appear suddenly;
- drivers become disoriented;
- people may lose direction within a short distance of shelter.
Whiteout vs blizzard
A whiteout is a visibility condition. A blizzard is a defined winter-weather event involving wind, snow, visibility and duration.
A brief snow squall can create a whiteout without lasting long enough to qualify as a blizzard.
Blowing Snow, Drifting Snow and Ground Blizzards
Blowing snow
Blowing snow is snow lifted from the ground and carried through the air by wind.
It may occur during active snowfall or after the precipitation ends.
Drifting snow
Snowdrifts form where wind slows and deposits transported snow.
Drifts commonly develop:
- behind buildings;
- along fences;
- beside road cuts;
- around parked vehicles;
- across exposed highways;
- on the downwind side of ridges;
- near vegetation and barriers.
Drift depth can greatly exceed the measured snowfall total.
Ground blizzard
A ground blizzard develops when strong winds lift loose snow already present on the ground.
It can occur:
- after a snowstorm has moved away;
- under clear or partly cloudy skies;
- with no new precipitation;
- days after snowfall when the snow remains dry and loose.
Ground blizzards are especially dangerous on open plains and tundra because the absence of falling snow may cause people to underestimate the risk.
Main Blizzard and Major Snowstorm Hazards
| Hazard | How it develops | Main consequences |
|---|---|---|
| Heavy accumulation | Long duration or intense snowfall rates | Blocked roads, roof loading and stalled transportation |
| Whiteout | Falling and blowing snow eliminate visibility | Crashes, disorientation and stranded travelers |
| Snowdrifts | Wind redistributes snow into deep banks | Reblocked roads and buried vehicles |
| Wind chill | Strong wind accelerates body heat loss | Frostbite and hypothermia |
| Wet-snow loading | Dense snow adheres to structures and vegetation | Tree damage, outages and roof failure |
| Power failure | Wind, snow or falling trees damage the grid | Loss of heat, communication and medical support |
| Isolation | Roads close and emergency access fails | Delayed rescue and supply shortages |
| Avalanche loading | Rapid mountain snow accumulation and wind transport | Unstable slopes and avalanche danger |
| Snowmelt flooding | Rapid warming or rain follows deep snow | Flooding, ice jams and roof runoff |
Why Blizzards Can Become Deadly
Blizzard fatalities often result from several hazards occurring at the same time rather than from snowfall alone.
Exposure
- hypothermia;
- frostbite;
- wet clothing;
- loss of shelter;
- wind-driven heat loss;
- exhaustion.
Mobility collapse
- vehicles become stuck in drifts;
- roads disappear beneath blowing snow;
- emergency vehicles cannot travel;
- people abandon cars and become disoriented;
- snowplows lose visibility;
- airport and railway operations stop.
Power and heating failure
- homes lose heat;
- medical devices lose power;
- water systems freeze;
- communications fail;
- unsafe alternative heating causes fires or carbon-monoxide poisoning.
Delayed medical care
- ambulances cannot reach patients;
- dialysis and medication access are interrupted;
- hospitals struggle with staffing;
- home-care visits are suspended;
- emergency repairs are delayed.
Travel and Transportation Impacts
Roads
- rapid snow accumulation;
- loss of lane markings;
- whiteout conditions;
- crosswinds;
- snowdrifts;
- multi-vehicle collisions;
- abandoned vehicles blocking plows;
- fuel shortages and prolonged entrapment.
Air travel
- runway closure;
- aircraft deicing delays;
- poor visibility;
- crosswind restrictions;
- crew displacement;
- cascading cancellations across airline networks.
Rail transport
- frozen or snow-packed switches;
- drifts across tracks;
- overhead-wire damage;
- reduced braking performance;
- blocked mountain routes;
- delayed freight and passenger trains.
Marine transport
Major winter cyclones may also produce:
- large waves;
- freezing spray;
- poor visibility;
- port closure;
- dangerous ice accretion on vessels.
Power, Buildings and Infrastructure
Electrical systems
- wet snow adheres to power lines;
- trees fall onto distribution networks;
- high winds damage conductors and poles;
- snow blocks access to repair sites;
- cold drives electricity demand upward.
Water systems
- pipes freeze;
- water mains break;
- pumps lose power;
- fire hydrants become buried;
- storm drains become blocked.
Communication networks
- towers accumulate ice or snow;
- backup batteries become depleted;
- fiber and power infrastructure are damaged;
- repair crews cannot travel.
Public services
- schools close;
- waste collection stops;
- emergency shelters open;
- deliveries are interrupted;
- fuel and food supplies become constrained.
Snow Loading and Roof Collapse
Snow depth alone does not determine structural load.
Ten centimeters of wet, dense snow can weigh far more than ten centimeters of dry powder.
Snow-load risk increases with:
- high liquid-water content;
- repeated storms;
- rain falling onto existing snow;
- partial melting and refreezing;
- uneven drifting;
- flat or poorly drained roofs;
- blocked gutters;
- weak or damaged structures.
Uneven loading
Wind can move snow from one side of a roof to another, creating concentrated loads that may be more dangerous than an evenly distributed layer.
After-Storm and Snowmelt Hazards
The end of snowfall does not mean the end of danger.
Blowing snow may continue
Strong winds can maintain whiteouts and rebuild drifts for hours after the main snow shield moves away.
Refreezing
Daytime melting can freeze again after sunset, creating black ice and dangerous walking conditions.
Falling snow and ice
Snow slabs, icicles and ice-coated branches may fall as temperatures rise.
Snowmelt flooding
Rapid warming, rain or blocked drains can produce:
- urban flooding;
- river flooding;
- ice jams;
- basement flooding;
- roof leaks;
- slope instability.
Avalanche danger
Heavy snow and wind can rapidly load mountain slopes. Avalanche science belongs in the dedicated Snow and Ice Avalanches pillar within Landslides and Mass Movements.
How Blizzards and Major Snowstorms Are Forecast
Forecasters combine current observations with numerical weather models and local climatology.
Important forecast variables
- storm track;
- central pressure;
- pressure-gradient strength;
- upper-level trough position;
- jet-stream structure;
- moisture transport;
- vertical temperature profile;
- snow-growth zone;
- snow-to-liquid ratio;
- surface and road temperature;
- wind speed and gusts;
- expected snowfall rate;
- duration;
- snow-band placement;
- existing snow available for blowing.
Forecast tools
- Surface stations: Temperature, wind, visibility and precipitation.
- Weather balloons: Vertical temperature, humidity and wind profiles.
- Radar: Snow-band location, intensity and movement.
- Satellites: Cloud structure, moisture and cyclone development.
- Numerical models: Possible storm tracks and precipitation patterns.
- Ensembles: Range of plausible outcomes and probabilities.
- Road sensors: Pavement temperature and icing potential.
- Snow observations: Existing snow available for drifting.
Why Snowfall Forecasts Change
Storm-track shifts
A small track adjustment can move the heaviest snow, rain–snow line and strongest winds by tens or hundreds of kilometers.
Temperature near freezing
A difference of one or two degrees can change:
- snow to rain;
- snow to sleet;
- dry snow to wet snow;
- road accumulation;
- snowfall ratio.
Snow-band placement
Narrow bands may produce extreme totals in one corridor and much less snow nearby.
Mixed precipitation
Sleet and freezing rain reduce snow totals while increasing travel and power hazards.
Compaction and melting
Snow may accumulate rapidly and then compact, partially melt or settle before the official measurement.
Blowing snow after precipitation
Forecast snow totals may be accurate while travel conditions become much worse because wind continues moving the snow.
How Snowfall Is Measured
Measuring snowfall is more complicated than placing a ruler in the deepest drift.
Fresh snowfall
Fresh snowfall is measured over a defined observation period on a representative surface or snow board.
Snow depth
Snow depth measures the total snow lying on the ground, including older snow and compaction.
Snow-water equivalent
Snow-water equivalent measures how much liquid water the snow contains.
Why measurements differ
- wind creates uneven drifts;
- snow compacts;
- snow melts between observations;
- different observers use different schedules;
- terrain and buildings affect deposition;
- automated gauges may undercatch snow in strong wind.
Blizzard Watches, Warnings and Advisories
Alert terminology varies by agency, but the general hierarchy is:
| Alert | General meaning |
|---|---|
| Outlook | A significant winter event may develop several days ahead. |
| Watch | Conditions are favorable, but timing, location or severity remain uncertain. |
| Advisory | Hazardous snow or winter conditions are expected below warning thresholds. |
| Winter storm warning | Heavy snow, mixed precipitation or dangerous winter conditions are expected. |
| Blizzard warning | Blizzard conditions are expected, imminent or occurring. |
| Snow squall warning | A short-duration but dangerous burst of snow and visibility loss is occurring or imminent. |
Local agencies may also issue alerts for:
- blowing snow;
- heavy snow;
- extreme cold;
- freezing rain;
- lake-effect snow;
- coastal flooding;
- avalanche danger.
Where Blizzards Occur
Blizzards are favored where cold air, moisture, strong winter cyclones and open wind-exposed terrain overlap.
| Region | Typical setup | Primary hazards |
|---|---|---|
| Great Plains and Canadian Prairies | Arctic air, intense continental lows and open terrain | Ground blizzards, severe drifting and prolonged road closure |
| Upper Midwest | Strong cyclones, cold air and abundant moisture | Heavy snow, wind, whiteouts and infrastructure disruption |
| Northeastern United States and Atlantic Canada | Atlantic coastal storms interacting with inland cold air | Heavy snow, blizzard conditions and coastal impacts |
| Great Lakes snowbelts | Lake-effect bands combined with strong wind | Localized extreme snowfall and abrupt whiteouts |
| Rockies and High Plains | Upslope flow, terrain and strong pressure gradients | Rapid snow accumulation, drifting and mountain travel danger |
| Northern and Eastern Europe | Atlantic cyclones, blocking and continental cold | Wind-driven snow, transport disruption and coastal exposure |
| Russia, Siberia and Central Asia | Severe continental cold and powerful winter winds | Ground blizzards, extreme wind chill and isolation |
| Northeastern China, Korea and Japan | Siberian air, winter monsoon and coastal moisture | Heavy snow, sea-effect enhancement and blowing snow |
| Patagonia and southern South America | Strong Southern Hemisphere cyclones and exposed terrain | Livestock losses, deep drifts and isolated communities |
| Antarctica and Arctic regions | Extreme cold, persistent wind and loose surface snow | Ground blizzards, zero visibility and severe exposure |
Major Snowstorm Patterns
Continental blizzard
A deep low crosses the interior of a continent while a strong pressure gradient generates powerful wind over open snow-covered terrain.
Typical impacts:
- widespread blowing snow;
- long-distance road closures;
- ground blizzards;
- livestock exposure;
- major drifting.
Coastal snow megastorm
A coastal cyclone draws moisture from a nearby ocean while cold air remains entrenched inland.
Typical impacts:
- heavy snow;
- strong winds;
- coastal flooding;
- mixed precipitation near the coast;
- major urban transport disruption.
Rapidly deepening winter cyclone
A low-pressure system intensifies explosively, creating a sharp pressure gradient and powerful winds.
Lake-enhanced synoptic snowstorm
A large winter cyclone produces widespread snow while cold airflow over open water adds localized heavier bands.
Atmospheric-river mountain snowstorm
A concentrated moisture plume reaches a mountain range while the snow level remains sufficiently low.
Typical impacts:
- extreme mountain snow;
- rapid avalanche loading;
- closed passes;
- deep roof accumulation;
- rain at lower elevations.
Historic Blizzard Categories and Examples
This section should remain selective. The page does not need an enormous chronological archive of every redirected post.
19th-century plains and prairie blizzards
Historic North American plains blizzards demonstrated the danger of:
- sudden temperature falls;
- open terrain;
- limited forecasts;
- poor transportation and communication;
- disorientation between farms, schools and settlements.
The Great Blizzard of 1888
The Great Blizzard of 1888 remains one of the best-known historic U.S. snow disasters, combining deep snowfall, powerful winds, severe drifting and prolonged transport paralysis across parts of the northeastern United States.
The Armistice Day Blizzard of 1940
This storm is remembered for rapid weather deterioration, severe wind, snow and deadly exposure across parts of the central United States.
The Iran Blizzard of 1972
The 1972 Iran blizzard is frequently cited among the deadliest snowstorms because of exceptional accumulation, buried settlements, isolation and prolonged exposure.
The Storm of the Century of 1993
The March 1993 storm affected a vast area of North America with heavy snow, severe wind, coastal impacts and widespread transportation disruption.
Blizzard Jonas in 2016
Blizzard Jonas produced major snowfall and shutdowns across parts of the Mid-Atlantic and northeastern United States, with blizzard conditions and coastal impacts in portions of the region.
The Buffalo Blizzard of December 2022
The Buffalo disaster demonstrated how intense wind, extreme cold, snow, lake enhancement, mobility failure and delayed rescue can combine into a deadly urban blizzard.
Thundersnow: Lightning Inside a Snowstorm
Thundersnow occurs when thunder and lightning develop while snow is falling.
It is favored by:
- strong upward motion;
- atmospheric instability;
- intense snow bands;
- rapidly deepening cyclones;
- lake-effect convection;
- mountain uplift.
Thundersnow can signal very high snowfall rates, but it does not automatically mean:
- the storm is a blizzard;
- the snow will become record-breaking;
- lightning will occur throughout the entire storm.
Keep thundersnow as a substantial section here and in the broader Winter Weather cornerstone rather than maintaining a thin standalone child pillar.
Blizzard Myths and Misconceptions
| Myth | Reality |
|---|---|
| Every heavy snowstorm is a blizzard. | Blizzards require severe wind and visibility conditions for a sustained period. |
| A blizzard must produce enormous snowfall. | Existing loose snow can create a ground blizzard with little or no new snowfall. |
| Whiteout and blizzard mean the same thing. | A whiteout is a visibility condition; a blizzard is a defined weather event. |
| A bomb cyclone is automatically a blizzard. | Bomb cyclone describes rapid pressure deepening, not surface visibility criteria. |
| Every nor’easter produces snow. | Nor’easters can produce rain, mixed precipitation, snow or combinations of hazards. |
| The polar vortex is a snowstorm. | The polar vortex is a large-scale circulation, not a specific surface storm. |
| More snow always means a more dangerous storm. | Wind, visibility, temperature, timing and infrastructure determine severity. |
| Four-wheel drive makes blizzard travel safe. | Four-wheel drive does not restore visibility or eliminate stopping-distance and entrapment hazards. |
| The storm is over when snow stops falling. | Blowing snow, drifting, refreezing and exposure hazards may continue. |
Blizzard and Major Snowstorm Safety
Before the storm
- Follow official forecasts and warnings.
- Postpone unnecessary travel.
- Charge phones, batteries and backup power.
- Prepare food, water and essential medication.
- Check heating systems and carbon-monoxide detectors.
- Protect exposed pipes.
- Fuel vehicles before conditions deteriorate.
- Prepare for pets and livestock.
- Know where emergency shelters are located.
Vehicle emergency kit
- blankets or sleeping bags;
- winter clothing and gloves;
- water and nonperishable food;
- flashlight;
- phone charger or power bank;
- shovel;
- traction material;
- ice scraper;
- first-aid supplies;
- bright cloth or visibility marker.
If stranded in a vehicle
- Remain with the vehicle unless safe shelter is clearly nearby.
- Call emergency services when possible.
- Keep the exhaust pipe clear of snow.
- Run the engine intermittently for heat.
- Open a window slightly when running the engine.
- Use visible markers to help rescuers locate the vehicle.
- Move periodically to maintain circulation.
- Avoid exhausting fuel and battery power.
At home
- Never use outdoor grills or generators indoors.
- Keep generators away from doors and windows.
- Monitor roof loading.
- Keep furnace and dryer vents clear.
- Check vulnerable neighbors.
- Avoid overexertion while shoveling.
- Stay away from fallen power lines.
During a whiteout
- Do not continue driving blindly.
- Reduce speed gradually.
- Move as far from active traffic as safely possible.
- Use hazard lights according to local guidance.
- Remain inside the vehicle.
- Do not attempt to walk through open terrain without a clearly identifiable nearby shelter.
Legacy Article and Redirect Classification
This pillar should absorb legacy articles whose dominant subject is heavy snow, blizzard conditions, whiteouts, blowing snow, severe drifting or broad snowstorm disruption.
Redirect here when the main story is:
- a blizzard;
- a major snowstorm;
- historic or record snowfall during a storm;
- a broad winter-storm snow emergency;
- whiteout conditions;
- blowing and drifting snow;
- a ground blizzard;
- vehicles or buildings buried by snow;
- major snow-related transportation disruption;
- livestock or communities isolated by snowfall;
- an anomalous off-season snowstorm where snow is the central event.
Redirect elsewhere when the dominant mechanism is:
| Dominant subject | Redirect destination |
|---|---|
| Cold air crossing open water and producing narrow snow bands | Lake-Effect Snow Explained |
| Freezing rain, glaze ice or destructive ice accretion | Ice Storms and Freezing Rain Explained |
| East Coast cyclone structure, coastal flooding or nor’easter identity | Nor’easters Explained |
| Explosive deepening or bombogenesis | Bomb Cyclones Explained |
| Arctic-air intrusion, cold wave or freeze impacts | Arctic Outbreaks and Cold Snaps Explained |
| Stratospheric vortex disruption or sudden stratospheric warming | Polar Vortex Explained |
| Snow or ice avalanche | Snow and Ice Avalanches pillar under Landslides and Mass Movements |
| Snow rollers or unusual natural snow formations | Strange Ice and Snow Phenomena |
| Snow devils or rotating snow columns | Vortex Phenomena |
Sources and Editorial Methodology
Blizzard definitions and warning criteria should be checked against the responsible meteorological authority for the affected country or region.
Preferred primary sources
-
NOAA National Weather Service Winter Weather Safety
-
National Weather Service Winter Storms and Blizzards
-
NOAA National Severe Storms Laboratory Winter Weather 101
- National meteorological-service storm reports and warnings.
- Official weather-station and snowfall observations.
- Radar and satellite archives.
- Official storm summaries and post-event analyses.
- Emergency-management guidance.
- Peer-reviewed atmospheric research.
StrangeSounds editorial rules
- Do not call every large snowstorm a blizzard.
- Identify which authority issued the blizzard warning.
- Distinguish forecast totals from measured snowfall.
- Distinguish snowfall from snow depth and drift depth.
- State when blizzard conditions occurred only in part of a storm.
- Do not use nor’easter, bomb cyclone and blizzard as synonyms.
- Separate wind chill from measured air temperature.
- Use local warning criteria.
- Update preliminary snowfall records after verification.
- Redirect events according to their dominant mechanism.
Frequently Asked Questions About Blizzards and Major Snowstorms
What is a blizzard?
A blizzard is a severe winter-weather event involving strong winds, falling or blowing snow, extremely low visibility and sustained duration.
What are the standard blizzard criteria in the United States?
Common U.S. criteria include sustained winds or frequent gusts of at least 35 mph, visibility of one-quarter mile or less and conditions lasting at least three hours.
Are blizzard criteria the same worldwide?
No. Wind, visibility, duration and warning terminology can differ between national meteorological authorities.
Does a blizzard require heavy snowfall?
No. A blizzard may develop when strong winds lift loose snow already on the ground, even with little or no new snowfall.
What is a ground blizzard?
A ground blizzard occurs when strong winds lift previously fallen snow and reduce visibility without significant new precipitation.
What is the difference between a blizzard and a snowstorm?
A snowstorm is defined mainly by falling and accumulating snow. A blizzard is defined by wind, airborne snow, low visibility and duration.
What is a major snowstorm?
A major snowstorm is a high-impact snow event causing substantial disruption through heavy accumulation, rapid snowfall, wind, drifting or structural loading.
Can a snowstorm produce more snow than a blizzard?
Yes. A storm can produce enormous snowfall without meeting the wind and visibility criteria required for a blizzard.
What is the difference between a whiteout and a blizzard?
A whiteout is a severe visibility condition. A blizzard is a defined weather event requiring strong wind, airborne snow, low visibility and sustained duration.
What causes blowing snow?
Blowing snow occurs when wind lifts loose snow from the ground and carries it through the air.
Why can snowdrifts become deeper than the snowfall total?
Wind removes snow from exposed locations and deposits it behind buildings, fences, vegetation and other obstacles.
What causes a major snowstorm?
Major snowstorms require cold air, moisture, atmospheric lift and an organized weather system capable of producing sustained precipitation.
What causes the strongest blizzard winds?
Strong winds commonly result from a tight pressure gradient around an intense low-pressure system, often combined with strong cold-air advection.
Can a nor’easter be a blizzard?
Yes. A nor’easter can produce blizzard conditions where wind, snow, visibility and duration meet the relevant criteria.
Is every nor’easter a blizzard?
No. Nor’easters may produce snow, rain, mixed precipitation, strong wind or coastal flooding without meeting blizzard criteria.
Can a bomb cyclone produce a blizzard?
Yes. A rapidly intensifying bomb cyclone can generate blizzard conditions, but explosive deepening alone does not make a storm a blizzard.
Is every bomb cyclone a snowstorm?
No. Bomb cyclones can occur over oceans or produce rain, wind, waves and coastal flooding without significant snow.
Can lake-effect snow produce blizzard conditions?
Yes. Strong wind and intense lake-effect snow can produce local blizzard conditions, although lake-effect snow has its own formation mechanism.
What is thundersnow?
Thundersnow is a snowstorm containing thunder and lightning, usually associated with strong lift, instability and intense snowfall.
Does thundersnow mean a storm is a blizzard?
No. Thundersnow describes electrical activity during snow, while blizzard classification depends on wind, visibility and duration.
What is the difference between wet snow and powder snow?
Wet snow is denser and stickier and creates heavier structural loads. Powder snow is lighter and more easily transported by wind.
Why are wet snowstorms damaging?
Dense wet snow adheres to trees, power lines and roofs, increasing the risk of broken branches, outages and structural failure.
Why are dry snowstorms dangerous?
Dry powder is easily lifted by wind, producing blowing snow, severe drifting, whiteouts and ground blizzards.
Why do snowfall forecasts change?
Small changes in storm track, atmospheric temperature, snow-band placement and precipitation type can dramatically alter local totals.
What is the difference between snowfall and snow depth?
Snowfall measures newly fallen snow during a defined period. Snow depth measures all snow present on the ground after settling, melting and drifting.
Why can a storm remain dangerous after snowfall ends?
Wind may continue producing blowing snow and drifts, while refreezing, extreme cold, falling ice and blocked roads remain hazardous.
What should you do if stranded in a blizzard?
Remain with the vehicle unless safe shelter is clearly nearby, contact emergency services, keep the exhaust clear and conserve fuel and battery power.
Where should lake-effect snow articles redirect?
Articles dominated by lake-fed snow bands should redirect to the dedicated Lake-Effect Snow pillar.
Where should bomb-cyclone snowstorm articles redirect?
Redirect to Bomb Cyclones when explosive deepening is the main subject. Redirect here when the central subject is snowfall, whiteout conditions, drifting or blizzard impacts.
