Snow Day Calculator

Predict the chance of a snow day based on weather forecast and school type. A fun prediction tool.

By Konstantin Iakovlev · Updated September 2026 · Source: NWS

inches
°F
mph
School Type

Snow Day Probability

30%

Unlikely

Snow Day Meter

UnlikelyPossibleLikelyCertain

Score

30/100

Confidence

Unlikely

This is a fun prediction tool and is not based on actual school closing decisions. Real snow day calls depend on road conditions, school district policies, and local emergency management.

Use the Snow Day Calculator above to calculate your results. Enter your values and see instant results — all calculations run in your browser.

Disclaimer: This calculator is for informational purposes only. Results are estimates based on the information you provide and the assumptions described on this page.

How It Works

Few things rival the anticipation of waking up to a possible school closure. This tool turns a few forecast numbers into a for-fun score that hints at whether classes might be called off. It knows nothing about your district's history or policies, and it is not a forecast model.

The score is a simple points total. Forecast snowfall carries the most weight: 5 points for at least 1 inch, 15 for at least 2, 25 for 4 to 8 inches and 40 for more than 8. Air temperature adds 5 points below 25°F, 10 below 20°F and 15 below 10°F, and wind adds 5 points above 15 mph and 10 above 25 mph. A Friday adds 15 points, a Monday 10, and a private school 5. The total is shown as a percentage but is not a statistical probability, and the highest possible score is 85: 30 or less reads 'Unlikely', 35 to 50 'Possible', 55 to 70 'Likely' and 75 or more 'Almost Certain!'. There are no inputs for ice or wind chill.

Treat the result as a bit of fun rather than a verdict. Districts weigh real-time conditions that no forecast fully captures, and a high probability here still does not override the official announcement, so check it directly. Local snow-removal capacity also skews outcomes in ways the percentage cannot show, since two towns facing identical snowfall may reach opposite decisions depending on how many plows they can put on the road.

Example: A Friday Snowstorm at Northwood High School

  1. 1 Input: public school, 6 inches of forecast snow, 15°F, 20 mph wind, Friday.
  2. 2 Points: 6 inches of snow (4 to 8 inches) = 25; 15°F (below 20°F) = 10; 20 mph wind (above 15 mph) = 5; Friday = 15; public school = 0.
  3. 3 Result: 25 + 10 + 5 + 15 = 55, shown as 55% and labeled 'Likely'.
  4. 4 Context: the same storm on a Tuesday scores 40 ('Possible'). The score reflects only the calculator's point table; the district's official announcement is the only answer that counts.

Source: NWS · Last updated: September 2026

Frequently Asked Questions

What factors determine a snow day?
Key factors include snowfall amount (4+ inches significantly increases chances), timing (overnight accumulation matters most), temperature, road conditions, wind chill, and the school district's cancellation history and policies.
How accurate are snow day predictions?
Snow day calculators are fun estimation tools, not scientific predictors. Actual decisions are made by school administrators based on real-time road conditions, weather service advisories, and bus route assessments, usually the morning of or the night before.
Do private schools and public schools cancel at the same rate?
Private schools often have different cancellation patterns since students typically travel farther and bus routes may be more complex. Some private schools cancel more readily, while others with boarding facilities may cancel less often.

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