Persistence Presents Problems
There are at least five different strategies in forecasting. One could look at trends, e.g. today is warmer than yesterday, so tomorrow will be warmer than today. Another method would use climatology. For instance, tomorrow’s high would look at the maximum temperatures that occurred on that particular day of the year and take the average of that data set. Thirdly, a more sophisticated way is called the analog method. For example, one would recognize the current pattern with a similar one that happened in the past and expect the same result. The fourth method is using numerical weather prediction. Finally, the fifth strategy is called persistence. One would forecast the weather to behave as it is currently. For example, using this strategy, one would expect it to rain tomorrow, since it rained today.
Although, in general, persistence wasn’t too bad over the last couple of months, this will be a rather poor method over the next couple of weeks. As the Northern Hemisphere is transitioning into the winter season, this will bring a more active weather pattern. In general, storms will be more frequent. As a result, one day might be rainy and cool, while the next, sunny and warm. With this active pattern, if you don’t like today’s weather, just wait for another day.
Tonight: Clear. Lows in the upper 30s°F. (4°C). West winds 5–10 mph.
Tomorrow: Sunny in the morning, then turning mostly cloudy. Highs in the upper 50s°F (15°C).
Thursday: Mostly cloudy. Rain showers in the morning. Highs in the mid 50s°F (13°C).
Friday: Partly sunny. Highs in the mid 40s°F (8°C).