Your Weather Folklore Questions Answered

As mentioned in a previous post, I was recently privileged with an opportunity to give a presentation on weather folklore at the Symphony in the Flint Hills. The audience asked some excellent questions during and after the talk, often sharing folklore sayings that they were familiar with.

We wanted to take this opportunity to answer some of these questions in greater depth.

About Lightning

First off, as to whether lightning comes down from the cloud or up from the ground, the answer is both. In general, a lightning bolt starts by descending to the ground in what is known as a leader stroke. Then a return stroke comes up from the ground to the cloud, creating the visible flash of light that we know as lightning. Typically, several leader and return strokes will follow each other in rapid succession, creating a flickering effect.

And, yes, it is true that you can tell how far away a lightning strike occurred by counting the seconds between the flash and the thunder. Every five seconds elapsed indicates one mile of distance. Therefore, one second indicates a fifth of a mile, five seconds one mile, ten seconds two miles, and so on.

When the Sky Rolls Up

Sometimes, objects on the horizon appear unusually large or close. Some people may be familiar with this effect under the term, “the sky rolling up.” This appears to be closely related to the phrase, “The farther the sight, the nearer the rain.” Air movement ahead of a front stirs up stagnant air and causes particles such as dust and pollen to settle out, increasing the visibility.

Westerly Winds

Sometimes we hear reports of “westerly winds,” but what does that mean? A westerly wind is the same as a west wind—that is, a wind from the west. Likewise with an easterly wind being from the east, a northerly wind from the north, and a southerly wind from the south.

The Persistence Forecast

One folklore saying suggests that you can forecast tomorrow’s weather by assuming it will be the same as today’s with about 67% accuracy. This type of forecasting is known as persistence, and unfortunately it is only about 50% accurate on average. However, this figure does improve somewhat during more settled weather patterns.

Interestingly, professional weather forecasters use the persistence forecast as a metric for evaluating their own accuracy. In some cases (again, most likely during periods of settled weather), meteorologists may even rely on persistence to produce a forecast, although this method is generally not highly regarded.

Signs of Winter

One thing that many amateur forecasters want to know is how soon winter is coming and how harsh it will be. Some of the best indicators include:

Early reddening of silver maple tree veins. From the Flint Hills eastward, personal observation suggests that the silver maple tree is a very reliable way to monitor the progress of the seasons. The leaves will start to show some reddening of the veins when the heat of summer is past. Early reddening means an early winter.
Trees slow to shed leaves. This usually indicates drought, which is associated with La Niña. La Niña in turn tends to cause frigid winters.
Early cessation of cool-season grass growth. Cool-season grass growth is partly determined by air temperature. When average daytime highs fall below 60 degrees F, the growth of these grasses will slow to a stop, marking the middle of fall and the approach of colder weather.
Early bird migration. Several factors influence the timing of bird migration, including any weather systems moving through the area. Thus, migratory birds may move out early if fall cold fronts arrive early.
Thick coats on cattle and other animals. While some scientists discount this sign of the seasons, numerous beef producers maintain that their cattle grow particularly thick, fuzzy coats in preparation for extreme cold. Cattle will also develop thicker skin and thicker layers of fat. (Cattle that receive inadequate nutrition will not show these adaptations.)

Signs of Spring

As for the old admonition to wait to set plants outside until the leaves of the hedge tree (Osage orange) are as large as squirrel’s ears, this is a very reliable saying due to the fact that the hedge tree is one of the last species to put out leaves in the spring.

Budding and leaf growth appear to be heavily influenced by soil temperature in native and adapted trees, with different species budding out at different times. This, in conjunction with the growth of wildflowers and grasses, creates a sort of natural calendar that can be very useful in the garden. For instance, elm trees bud out in the final days of winter, a good time to start slow-growing seedlings indoors. Likewise, smooth brome begins growth in early spring, when it is time to seed the hardiest vegetables in the garden.

My Favorite Weather Myth

Finally, if I had to pick a favorite weather myth, I would choose the infamous groundhog forecaster, Punxsutawney Phil. With an accuracy of about 50% according to NOAA, poor Punxsutawney Phil is totally adorable, but not particularly useful.