Data Sources & Meteorological Provenance
The Snow Day Calculator relies exclusively on authoritative US public datasets. We do not invent weather forecasts, purchase synthetic black-box models, or monetize private location tracking.
National Weather Service (NOAA)
The National Oceanic and Atmospheric Administration (NOAA) and the National Weather Service (NWS) operate Doppler radar networks, GOES weather satellites, and numerical weather prediction supercomputers across 122 regional Weather Forecast Offices (WFOs).
- Hourly commute weather forecasts (5:00 AM – 9:00 AM)
- Winter Storm Warnings, Watches & Ice Storm Warnings
- Local WFO Hazardous Weather Outlook (HWO) discussions
NOAA NCEI 1991–2020 Normals
Official 30-year baseline climate statistics from the National Centers for Environmental Information. Used to benchmark seasonal snowfall averages, days with measurable snow ($\ge 1"$), and coldest month mean temperatures.
- Certified local observation station historical snowfall records
- Haversine station distance and elevation difference verification
- Explicit provenance labeling (“Local Station” vs. “Regional Estimate”)
US Census Bureau & Gazetteer Files
Rather than transmitting user searches to commercial advertising tracking networks, our platform uses an embedded, chunked static US postal directory compiled from official Census Bureau coordinates.
- 41,865 active US residential postal delivery codes
- 29,929 US incorporated places and Census-Designated Places
- Disambiguation of cities sharing identical names across states
National Center for Education Statistics
The Common Core of Data (CCD) is the US Department of Education's primary database on public elementary and secondary education, maintaining directories of local education agencies (LEAs).
- Over 13,000 public school district boundaries and profiles
- Verified official district emergency closing portals
- Student enrollment sizing and geographic agency categorization
Data Freshness & Transparency Architecture
During major winter storms, hundreds of thousands of parents and students check weather conditions simultaneously. To protect government weather servers and maintain rapid page loads, our system uses an optimized static chunked data architecture: