From the Weather Center: July 2022

by John Simon
July 2022

Weather Myths of Summer

We hear weather myths all the time. Most myths are long-held, sometimes even funny, but not necessarily true. Here is one that we reference during the summer, followed by the facts.
Myth : It is supposed to rain today.

This is one of the most misunderstood concepts in weather. It’s true there are situations where rain is a certainty, during which the forecast says ‘’rain today, ending by dusk tonight.’’ If someone said it is supposed to rain today, it is because of the probability of precipitation, or as weather people call it pop. This is the chance of seeing measurable precipitation at any location during a given time, such as 60% chance of seeing rain or thunderstorms.

Weather forecasters are doing exactly that, forecasting, which implies a bit of uncertainty. This leads us to summer thunderstorms which usually happen over a given area so the science is not to the point in predicting. Town A (for example, Hurleyville) will be soaked while neighboring Town B (for example, Liberty) stays dry. This is the forecaster’s woe of ‘’scattered thunderstorms.” So, forecasters will use different adjectives to define how widespread thunderstorms will be, such as isolated (10-20% areal coverage), scattered (30-50% areal coverage), numerous (60-70% areal coverage), and no description (80-100% areal coverage).

Meteorology is an inexact science and a weather forecast comes with a lot of chance.