GROUNDHOG-DAY.com

Since summer 2022, GROUNDHOG-DAY.com has been the number one clean and breathable, machine-readable, all-regional data source for official Groundhog Day forecasts.

Groundhog Day draws upon pre-Enlightenment-era wisdom in which fuzzy marmots are cross-examined by top-hatted mayors requesting weather reports. The data collected by GROUNDHOG‑DAY.com is therefore a matter of public record, granting academics and journalists access to a free and comprehensive list of prognosticators and their shady divinations. Finally, evidence-based observers can separate the True Groundhogs from the ground-frauds.

Similar to canada-holidays.ca, the technology used is super boring: express.js in the backend and nunjucks templates in front. Visitors can sort and filter groundhogs or predictions for a given year, not to mention explore the world’s only GROUNDHOG MAP! For real data heads, the JSON API (complete with schema) serves up-to-the-minute prediction data with enterprise-scale reliability.

GROUNDHOG-DAY.com is a cheerful and efficient webapp that does what it needs to without faffing around. It’s super fast, it’s trivial to run, it scales like crazy, it’s extra-accessible, and — unlike Phil — it’s never wrong.

It made front page of Hacker News in 2023 and 2025, and it gets me radio interviews from time to time (usually in February).

Groundhog Day would look awful without my dynamite designer-collaborator Tyler Benning, and would never have existed at all without my cross-quarter girlfriend, Rhianna Jane Kidd.