2 hour delay calculator
Your school
Next school day
Late start–%
Snow day–%
Enter a ZIP code above
Will there be a snow day?
- An estimate from the public forecast. Your school district makes the call.
Why the sign says so
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Snow
How many inches are forecast, against what your area usually handles.
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Timing
Whether it falls overnight or stops early enough for plows to finish.
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Ice
Freezing rain, which closes schools at far smaller amounts than snow.
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Cold
The wind chill while children wait for the bus.
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Wind
Gusts strong enough to drift snow back over cleared roads.
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Alerts
Winter warnings and advisories from the National Weather Service.
Set from your state when you check a ZIP code. Change it if you know your district better.
Worked out in your browser from the National Weather Service forecast. No account, no cookies.
The chance school starts late, next to the chance it closes, from the official forecast for your ZIP code.
Delay or closure
The two numbers on the sign add up to the chance of any disruption. A light or early storm puts most of it on the late start; a heavy overnight one moves it to the closure. How districts choose between a delay and a closure.
| Snow | Closes for a dusting | Closes for a few inches | Used to snow | Almost never closes |
|---|---|---|---|---|
| 1 in | 44%, 50% | 9%, 6% | 2%, 3% | 1%, 3% |
| 2 in | 1%, 98% | 42%, 21% | 9%, 6% | 4%, 4% |
| 3 in | 0%, 99% | 44%, 50% | 23%, 12% | 9%, 6% |
| 4 in | 0%, 99% | 20%, 79% | 42%, 21% | 17%, 10% |
| 6 in | 0%, 99% | 1%, 98% | 44%, 50% | 42%, 21% |
Snow that stops before midnight tilts the result toward a delay: in a district used to snow, 6 inches ending at midnight gives 35% for a late start and 17% for a closure.
Questions about delays
What is a two-hour delay?
School starts two hours later than usual and buses run the same routes two hours late. The day usually ends at the normal time. Some districts use one-hour or three-hour delays.
When do schools delay instead of closing?
When the trouble is expected to pass: snow that ended overnight and needs a few more hours of plowing, ice that will melt after sunrise, or wind chill that eases by mid-morning.
Can a delay turn into a closure?
Yes. A district may call a delay to buy time and close if roads have not improved by the delayed start.
How is the chance of a delay worked out?
A late start needs less bad weather than a closure. The calculator works out the chance of any disruption from the same score with a 1.7-times head start, then takes away the chance of a full closure. What is left is the chance of a late start instead.