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24-hour precipitation, played forward

Wettest 172 mm at 34.75N 71.25W · Thu 18Z to Fri 18Z

One GFS run, issued 18Z 24 Sep — played forward 6 hours at a time, from 24 to 240 hours out.

Methodology

Each frame is the precipitation this run puts down in the 24 hours to it — its total at that hour less its total 24 hours before — so the film starts at +24 h, the first frame with a whole day behind it. Liquid-equivalent: snow counts as the water it melts to.

The colours are Tropical Tidbits' scale, so a reader who knows theirs can read this one. Three of its steps are re-shaded: at 0.5 in, at 2 in — where, on theirs, a reader with protanopia sees the 1.75–2 in band and the 2–2.5 in band as one colour — and among the yellows above 12 in. Same hues; the lightness is re-spaced so every step is visible in every common form of colour-blindness.

Six-hourly to 240 hours. GFS forecasts out to 384 hours; this film stops at 240. The frames past the one shown load on demand. Uncorrected model output.

This map is drawn from model output we store ourselves, not from anyone's picture of it, and is based on data and products of NOAA. The per-city read of the same day — which cities the models are fighting about, and what the discussion makes of it — is on the national page.

Sources and licences

What we change: each field is cropped to the frame these maps share when we download it, and each map then smooths, contours, differences or ranks those numbers as its Methodology says. These are our maps of the providers' numbers, not their products, and none of them has reviewed or endorsed this site.

Coastlines, borders, lakes and place names: Natural Earth, public domain.