The Spread

Which weather model is most accurate in your city?

The Spread — the forecast spread — archives what every major model predicted, then scores those forecasts against what actually happened. The honest headline, most days and most places: it's close. Where nobody leads by more than the noise, this page says so and shows the whole field — a crown won by a tenth of a degree is a coin flip wearing a ribbon. Pick a city:

Every model's typical miss at one day out — one dot per model, every city on one scale.
City The race Verdict Spread today
Atlanta, Georgia ECMWF & UKMO within 0.04°F 4°F
Berlin, State of Berlin ICON & ECMWF within 0.03°F 3°F
Boston, Massachusetts UKMO & ICON within 0.08°F 6°F
Buffalo, New York UKMO & ICON within 0.24°F 12°F
Charlotte, North Carolina AIGFS & GEM within 0.27°F 8°F
Chicago, Illinois ICON & GFS within 0.3°F 7°F
Dallas, Texas AIFS & AIGFS within 0.03°F 3°F
Denver, Colorado UKMO & GFS within 0.13°F 5°F
Detroit, Michigan UKMO by 0.42°F over GFS 8°F
Houston, Texas GEM & ICON within 0.05°F 3°F
London, England ICON & ECMWF within 0.16°F 4°F
Los Angeles, California UKMO & ECMWF within 0.02°F 11°F
Miami, Florida UKMO & ICON within 0.05°F 8°F
Milan, Lombardy ICON by 0.54°F over AIGFS 3°F
Minneapolis, Minnesota AIFS & ECMWF within 0.24°F 17°F
New Orleans, Louisiana ICON by 0.43°F over ECMWF 8°F
New York, New York AIFS by 0.86°F over ICON 6°F
Oklahoma City, Oklahoma ICON & ECMWF within 0.05°F 6°F
Orlando, Florida AIGFS by 0.66°F over UKMO 13°F
Paris, Île-de-France Region ICON & AIGFS within 0.13°F 3°F
Philadelphia, Pennsylvania UKMO & AIFS within 0.04°F 2°F
Phoenix, Arizona ECMWF by 0.55°F over ICON 12°F
Salt Lake City, Utah ICON & GFS within 0.29°F 13°F
San Antonio, Texas ECMWF & UKMO within 0.06°F 3°F
San Diego, California GFS & ICON within 0.14°F 9°F
San Francisco, California ECMWF by 0.53°F over GEM 5°F
Seattle, Washington UKMO & ECMWF within 0.07°F 7°F
St. Louis, Missouri ICON & ECMWF within 0.24°F 6°F
Tampa, Florida AIGFS by 0.43°F over AIFS 7°F
Washington, District of Columbia UKMO & GEM within 0.34°F 6°F

What one scored day looks like

The most recent day we settled, whichever way it went — not the one that flatters the models.

9 days out, 5 models put Oklahoma City's Fri Aug 28 high anywhere from 88° to 114°; by the final call they had settled to a median of 99°. It hit 100° — UKMO landed closest, off 0.3°.

Each bar is the full range of the models still forecasting that day, in °F; the rule is what the OKC observations recorded. This one opened 26° wide and closed to 4°. Across every day we have scored, the range narrows even though more models arrive as the day approaches — a median 11.6° at 13 days out with four models, 5.8° on the day with seven. See this day's full receipt →

More scored days

The next-most-recent settled days across the archive — records, not rankings: each bar is the models' opening range, the rule is what happened.

  • Washington · Fri Aug 28

    5 models opened 85–90° at 8 days out; it hit 90° — GFS closest, off 0.1°.

    Full receipt →

  • Tampa · Fri Aug 28

    7 models opened 84–94° at 3 days out; it hit 89° — UKMO closest, off 0.4°.

    Full receipt →

  • St. Louis · Fri Aug 28

    7 models opened 83–86° at 3 days out; it hit 87° — GFS closest, off 0.4°.

    Full receipt →

  • Seattle · Fri Aug 28

    7 models opened 69–77° at 5 days out; it hit 73° — GEM closest, off 0.1°.

    Full receipt →

How the scoring works

Each model's 1-, 3-, and 7-day-ahead forecasts are captured from its actual archived runs (nothing is reconstructed after the fact), then verified against each city's truth — its own station's observations where one is pinned, the ECMWF IFS analysis otherwise — once the day has happened. Bias is the signed average error — positive means the model ran warm. The typical miss (MAE) is the average absolute error. Cities join these pages as they join The Spread's archive.

Two things you should know about the yardstick. Where a city is pinned to its own station, models are verified against that thermometer's observed highs outright, and the city page names the station. Everywhere else, truth is the ECMWF IFS analysis — ECMWF's operational product, a grid rather than a thermometer, while two of the seven models scored here are ECMWF's own. Every registry city has been pinned to its station since 2026-08-22, so the grid is the yardstick only for places no thermometer serves, and those pages say so.

The Spread itself is in closed beta — these verification pages and the Updates log are public while the rest of the product is gated. If you want in, ask for an invite — say where you forecast and I will send you one.