Old Tappan is a small town of about 6,016 people in NJ, sitting at 41.0°N in a temperate climate zone. NWS, American, European each forecast Old Tappan with their own physics, so we line all three up and flag where they disagree. Nearby towns include River Vale, Norwood, Tappan.
We grade every model against the weather that actually happened, so you can see which forecast model is most accurate in United States before you trust any single number.
The CheckWeather Score blends temperature, wind and rain accuracy — each measured against ERA5 (the recorded weather) over the last 30 days across 1999 cities. Lower error means a higher score. See which forecast model is most accurate in United States, how we measure forecast accuracy, or which model each weather app uses.