Every hour this site archives the raw material of the local weather story — METARs, TAFs, forecast snapshots, the NWS grid, alerts, model soundings and every forecast discussion. This page is the reading room: pick any archived day and see what happened, what was forecast, and how the two compare. Live views: weather · discussion.
Top band: the flight category, same colors as the calendar. Solid lines are what was observed — the archive's verification station, and optionally the field's own sensor in a lighter shade of the same color; dashed lines are the NWS grid archived that morning, the day as forecast laid over the day as flown. Every lane keeps its own scale (no shared or hidden second axis), and night is shaded. Hover or tap anywhere for every value at that moment.
One bar per alert, on the day's clock — the meteogram's hours, widened only for an alert that began before this day or ran past it. Ticks are issuances: a watch updated three times is one bar with four ticks, not four rows. The dotted run-in is the lead time between the first issuance and onset. Night is shaded; a date instead of an hour marks midnight. Open a row for every issuance and its text.
Top: the category the TAF in force called for (FM base, BECMG folded in; TEMPO and PROB not counted). Bottom: the METAR nearest the hour, within 45 min. No bottom = not judged.
NEXRAD composite → IEM · yellow → KANP · grey → archived stations
Nothing archived for this day.
Daily temperature span (KDCA, each bar min → max of the day's own METARs), colored by the day's high. Below: the day's worst daytime flight category, and dots for days with rain (·) and thunderstorms (⚡) in the METARs.