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MSLP + precip rate

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GFS · Run 18Z 4 Oct · +0 h · Valid Sun 18Z 4 Oct

Region Southeast

United States

Lower 48 Northwest Southwest Northern Plains Southern Plains Midwest Northeast Mid-Atlantic Southeast

Europe

Europe

The readings under the map are for the whole map, not only the part shown.

Surface pressure (hPa) and instantaneous precip rate (in/h)

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GFS · Run 18Z 4 Oct · +0 h · Valid Sun 18Z 4 Oct

Surface pressure (hPa) and instantaneous precip rate (in/h)

Heaviest rate 0.948 in/h, near 20.0N 113.5W · unshaded ground is where the model has under 0.01 in/h falling

One GFS run — issued 18Z 4 Oct — played forward 6 hours at a time, from its analysis to 384 hours out.

Methodology

Step forward and the pressure pattern moves, and the precipitation under it moves with it: that motion is the weather this run forecasts, not the forecast changing — Forecast Evolution is the film for that. Same chart grammar as the surface analysis: the same reduction, the same 4 hPa interval, the same frame; only the forecast hour varies. Six-hourly to 384 hours. GFS forecasts out to 384 hours. The frames past the one shown load on demand.

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. Every model's full forecast for any of these cities, or anywhere else, is in the beta: request an invite; it's free during the beta.

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.