Cold Snaps — What Causes Sudden Temperature Drops

What Is a Cold Snap?

A cold snap is a rapid and significant drop in temperature, often 10-20°C within 24 hours. Unlike gradual seasonal cooling, cold snaps arrive suddenly and can catch people off guard.

What Causes Cold Snaps?

The most common cause is an Arctic air outbreak — when the polar jet stream dips south, allowing frigid Arctic air to spill into lower latitudes.

Other triggers include:

• Cold fronts: A mass of cold air displacing warm air
• Polar vortex disruption: Weakening of the polar vortex sends cold air southward
• Radiational cooling: Clear skies and calm winds after a front passes allow temperatures to plummet overnight

Impact

• Pipes can freeze and burst if temperatures drop below -5°C in poorly insulated buildings
• Road black ice forms when temperatures drop below freezing after rain
• Plants suffer frost damage when cold snaps hit during growing season
• Energy demand spikes as heating systems work overtime
• Hypothermia risk for homeless populations and outdoor workers

How to Prepare

• Insulate exposed water pipes before winter
• Keep emergency supplies: blankets, torch, bottled water, food
• Check on elderly or vulnerable neighbours
• Bring pets indoors
• Let taps drip slightly to prevent pipe freezing
• Keep your car's fuel tank at least half full during cold snaps

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