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MSLP + precip rate

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Region Lower 48

United States

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Europe

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

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ECMWF · Run 12Z 15 Oct · +0 h · Valid Thu 12Z 15 Oct

ECMWF · Run 12Z 15 Oct · +0 h · Valid Thu 12Z 15 Oct

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

Heaviest rate 0.753 in/h, near 34.0N 99.0W · unshaded ground is where the model has under 0.01 in/h falling

One ECMWF run — issued 12Z 15 Oct — played forward 6 hours at a time, from its analysis to 360 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 2 hPa interval, the same frame; only the forecast hour varies. Six-hourly to 360 hours. ECMWF's 00Z and 12Z runs forecast out to 360 hours, its 06Z and 18Z runs to 144. 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 the European Centre for Medium-Range Weather Forecasts (ECMWF). 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
  • ECMWF: IFS, from ECMWF's open data. This service is based on data and products of the European Centre for Medium-Range Weather Forecasts (ECMWF). Source: www.ecmwf.int. This ECMWF data is published under a Creative Commons Attribution 4.0 International (CC BY 4.0). ECMWF does not accept any liability whatsoever for any error or omission in the data, their availability, or for any loss or damage arising from their use.

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.