Above is a comparison of our API's maximum, and minimum temperature forecasts for the last 30 days against 6 other competitors including the NOAA National Weather Service (NOAA NWS). Forecasts are out 5 days into the future with "Forecast Day 1" being the next day's forecast. A couple of things to note for this comparison:
Error values are in degrees Fahrenheit, and lower values indicate greater forecast accuracy.
Max/Min temperatures (calculated from midnight to midnight local time) are used instead of High/Low as most competitors do not report High/Low temperatures.
Values are the mean absolute error for both maximum, and minimum temperatures combined.
Forecasts are validated against 500 randomly selected global ASOS, and METAR stations with excellent data quality as well as a minimum of 20 years of record.
End of local day forecasts are taken once per day per location, and the forecast times vary based on location timezone - 00:00 UTC for the Americas, 18:00 UTC for EU & Africa, and 12:00 UTC for others.
Mean error for both Max/Min temperature (degrees F) from our API for forecast days 1-5, broken down by region. Our closest competitor is included for comparison.
Mean High/Low temperature forecast errors (degrees F) for the past 30 days from our API going out to 5 days into the future.