The Forecast Race
In December 2025, NOAA started running an AI weather model next to its regular ones. Does it beat the Weather Service's own forecasters? Every morning we save what five forecasters say about tomorrow in La Porte, and the next day we grade them against the La Porte airport. Nothing here is our forecast. We just keep score, in public.
NOAA's AI vs. the Weather Service
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The standings
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Average miss: how far each forecast temperature was from the airport reading, averaged over every check. Lower is better. When two show the same average miss, the one with more checks within 3° ranks higher. Days won: the days a forecaster had the smallest average miss on its own.
What each one says about tomorrow
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How they did
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Every graded day
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The rules
- The racers: the National Weather Service's official forecast (made by its forecasters at NWS Northern Indiana), NOAA's AI model (AIGFS), NOAA's regular model (GFS), Europe's AI model (AIFS) and Europe's regular model (ECMWF IFS). Europe's two joined on Oct. 4, 2026.
- When: every morning at 5:30 Central we save what each one says about tomorrow: the Weather Service forecast as it stood at 5:30, and each model's run from 7 PM the evening before (6 PM in winter).
- What: the temperature at four times, 1 AM, 7 AM, 1 PM and 7 PM (midnight, 6 AM, noon and 6 PM in winter), and whether it rains at least 0.01 inch over those 24 hours.
- The judge: the automated weather station at the La Porte Municipal Airport (KPPO), the same one that grades the Daily Scoop. A forecast is a hit when it's within 3 degrees.
- Where: the Weather Service's forecast grid point nearest the airport, and each model's forecast for the airport's exact spot.
- Honest: saved forecasts are never changed. If a racer's data doesn't come in one morning, it isn't scored that day. The forecasts made Sept. 27 to Oct. 5, 2026, before the race began, were filled in on Oct. 6 from the same public archives, using the same 5:30 AM cutoff.
Questions
Is this La Porte Weather Now's forecast?
No. We only keep score. Our own written forecast, the Daily Scoop, is graded on the Track Record page. For official forecasts and warnings, follow the National Weather Service.
What is NOAA's AI model?
The Artificial Intelligence Global Forecast System (AIGFS). NOAA put it into service on Dec. 17, 2025, built at first on Google DeepMind's GraphCast and trained further on NOAA's own data. NOAA says it uses a tiny fraction of the computing power of its regular model and shows better skill for many large-scale weather features. This race checks how it does at one small airport in Indiana. (NOAA announcement)
Why those four times of day?
Every forecaster in the race gives a temperature for those times. The two AI models give temperatures only every six hours, at 1 AM, 7 AM, 1 PM and 7 PM in summer time (midnight, 6 AM, noon and 6 PM in winter), so those are the times we can compare everyone fairly. The day's high and low usually fall between those checks, so the race is about the whole day, not just the high.
Isn't it unfair to the Weather Service?
We tried to make it even. Everyone's forecast is the one available at 5:30 AM the morning before: the Weather Service's official forecast as its forecasters had it then, and each computer model's run from the evening before. Nobody gets a later look. The Weather Service forecasters see the models, which helps them; the models can't see the forecasters.
When can you say who's better?
Not for a while. A few days of weather can make anyone look good or bad, so we say "too early to call" until there are at least 14 graded days, and the real answer will take months and every kind of weather, including lake-effect snow.
Sources: NOAA: AI weather models announcement · NWS forecast grids (NDFD) on AWS · NOAA NOMADS (AIGFS, GFS) · ECMWF open data (CC BY 4.0) · KPPO readings, Iowa Environmental Mesonet · The race's data (race.json)
Europe's two models: this service is based on data and products of the European Centre for Medium-Range Weather Forecasts (ECMWF). Source: www.ecmwf.int. Licence: 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. Changes: we read single forecast values for one spot. NOAA data is public domain.