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

Region Mid-Atlantic

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

3030303030303030404040404040404040404040404040505050505050505050505060606060607070707070707070707070707080808080808067°Oklahoma City: 67 °F at 12Z 15 Oct39°Salt Lake City: 39 °F at 12Z 15 Oct48°Seattle: 48 °F at 12Z 15 Oct70°Orlando: 70 °F at 12Z 15 Oct55°New York: 55 °F at 12Z 15 Oct58°Los Angeles: 58 °F at 12Z 15 Oct58°Chicago: 58 °F at 12Z 15 Oct68°Houston: 68 °F at 12Z 15 Oct50°Phoenix: 50 °F at 12Z 15 Oct72°Dallas: 72 °F at 12Z 15 Oct60°Atlanta: 60 °F at 12Z 15 Oct54°Boston: 54 °F at 12Z 15 Oct68°Washington: 68 °F at 12Z 15 Oct42°Denver: 42 °F at 12Z 15 Oct49°Minneapolis: 49 °F at 12Z 15 Oct81°Miami: 81 °F at 12Z 15 Oct56°San Francisco: 56 °F at 12Z 15 Oct72°New Orleans: 72 °F at 12Z 15 Oct51°Buffalo: 51 °F at 12Z 15 Oct60°Charlotte: 60 °F at 12Z 15 Oct57°Philadelphia: 57 °F at 12Z 15 Oct56°Detroit: 56 °F at 12Z 15 Oct73°Tampa: 73 °F at 12Z 15 Oct57°San Diego: 57 °F at 12Z 15 Oct68°St. Louis: 68 °F at 12Z 15 Oct73°San Antonio: 73 °F at 12Z 15 Oct

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

One GEM run — issued 12Z 15 Oct — played forward 6 hours at a time, from its analysis to 120 hours out.

Methodology

Nights and days pass as you step this run: that motion is the weather the run forecasts, not the forecast changing. Forecast Evolution is the other film — it holds one moment still and steps the runs, so the only thing that moves there is the model's mind. The colour scale is fitted to the whole run at once, so the same moment reads with more bands here than on the static GEM map; the field is identical. 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.

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

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.