MSLP + precip rate
GEM · Run 12Z 15 Oct · +6 h · Valid Thu 18Z 15 Oct
Region Northwest
United States
Europe
The readings under the map are for the whole map, not only the part shown.
Surface pressure (hPa) and 6-hour averaged precip rate (in/h)
GEM · Run 12Z 15 Oct · +6 h · Valid Thu 18Z 15 Oct
Surface pressure (hPa) and 6-hour averaged precip rate (in/h)
Heaviest 6-hour mean 0.29 in/h, near 33.15N 99.9W · unshaded ground is where the model has under 0.01 in/h falling
Heaviest 6-hour mean 0.421 in/h, near 31.95N 100.2W · unshaded ground is where the model has under 0.01 in/h falling
Heaviest 6-hour mean 0.664 in/h, near 29.55N 102.0W · unshaded ground is where the model has under 0.01 in/h falling
Heaviest 6-hour mean 0.672 in/h, near 27.3N 104.4W · unshaded ground is where the model has under 0.01 in/h falling
Heaviest 6-hour mean 0.687 in/h, near 28.05N 88.05W · unshaded ground is where the model has under 0.01 in/h falling
Heaviest 6-hour mean 0.424 in/h, near 28.05N 88.05W · unshaded ground is where the model has under 0.01 in/h falling
Heaviest 6-hour mean 0.61 in/h, near 20.55N 90.15W · unshaded ground is where the model has under 0.01 in/h falling
Heaviest 6-hour mean 0.279 in/h, near 53.25N 128.4W · unshaded ground is where the model has under 0.01 in/h falling
Heaviest 6-hour mean 0.367 in/h, near 20.7N 95.85W · unshaded ground is where the model has under 0.01 in/h falling
Heaviest 6-hour mean 0.62 in/h, near 21.15N 87.75W · unshaded ground is where the model has under 0.01 in/h falling
Heaviest 6-hour mean 0.525 in/h, near 20.1N 95.4W · unshaded ground is where the model has under 0.01 in/h falling
Heaviest 6-hour mean 0.438 in/h, near 20.1N 106.5W · unshaded ground is where the model has under 0.01 in/h falling
Heaviest 6-hour mean 0.639 in/h, near 20.1N 106.65W · unshaded ground is where the model has under 0.01 in/h falling
Heaviest 6-hour mean 0.729 in/h, near 20.25N 106.2W · unshaded ground is where the model has under 0.01 in/h falling
Heaviest 6-hour mean 0.371 in/h, near 34.35N 67.8W · unshaded ground is where the model has under 0.01 in/h falling
Heaviest 6-hour mean 0.428 in/h, near 34.8N 68.25W · unshaded ground is where the model has under 0.01 in/h falling
Heaviest 6-hour mean 0.444 in/h, near 35.1N 66.75W · unshaded ground is where the model has under 0.01 in/h falling
Heaviest 6-hour mean 0.315 in/h, near 36.15N 70.35W · unshaded ground is where the model has under 0.01 in/h falling
Heaviest 6-hour mean 0.541 in/h, near 37.5N 70.2W · unshaded ground is where the model has under 0.01 in/h falling
Heaviest 6-hour mean 0.769 in/h, near 38.1N 70.2W · unshaded ground is where the model has under 0.01 in/h falling
One GEM run — issued 12Z 15 Oct — played forward 6 hours at a time, from 6 hours out to 120 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 120 hours. GEM forecasts out to 240 hours; this film stops at 120. The frames past the one shown load on demand. GEM publishes no precipitation rate, so the shading here is the 6-hour mean rate — the run's total precipitation at each frame less the total 6 hours before, over 6 — on the same scale as the instant the other models shade with. A mean over 6 hours is smoother and weaker than an instant, so its heavy bands light less often on the same weather; and because no 6-hour bucket ends at the analysis, this film opens at +6 h rather than showing one frame with no rain under it.
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 Environment and Climate Change Canada. 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
- Environment and Climate Change Canada: GEM, from the MSC Datamart. Data Source: Environment and Climate Change Canada, under its Data Services End-use Licence.
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.