From peach orchards to porch conversations, weather is always part of the story in the South — and University of Georgia climatologist Pam Knox brings clarity, science and common sense to every weather event.
Whether you’re wondering why the seasons feel out of sync, how climate change plays out in your backyard, or what to expect before the next storm, Knox offers answers grounded in decades of research and a deep connection to the land. It’s your forecast with context.
How are weather patterns changing?
When you change the heat in the world as a whole, it’s not changing evenly. It’s getting much hotter in the polar regions relative to their average temperature, but the equator is not changing that much. In the polar regions, you’re getting rid of a lot of stuff that’s highly reflective, like snow and ice, so there it is warming up much faster. The temperature difference between the equator and poles is changing, and as that temperature difference gets smaller, it allows the circulation of the atmosphere between them to get more wavy. You get more low-pressure centers going through, more high-pressure centers going through, and every time you get one through, the wind pattern changes and the temperature changes, so we’re seeing more variation in the weather.
As we change the temperature pattern on the globe, we’re starting to see changes in how the weather patterns in the atmosphere influence the local climate. It doesn’t mean we’ve never had that before. We’ve had cold outbreaks before, but certainly not a lot of places set records for snowfall. Part of that is because we have more water vapor too, so you’re going to get these more variable patterns. It’s terrible for farmers. Farmers like to have consistency.
Are changing weather patterns making forecasting less reliable?
What you’re seeing is more variability. So, even though it was so cold here in January, Europe was setting record highs, and the world set a record for January. We are just a small part of the world, but here is where we live, so that’s what we notice. It could have easily happened that we would have had warmer air and Europe would have had colder air in a different year.
This makes it hard to predict, because we’re supposed to be in a La Niña this year, and usually La Niña winters are warmer and drier than usual. This year the drier has certainly been true. We’ve been quite dry even with the snow because it looked impressive, but it didn’t have very much water and it didn’t last for very long. The advantage is that snow melts slowly, so most of it gets into the ground. It’s time-released water more than anything else.
Are all these changes in weather patterns making it harder to predict what the weather is going to do here?
It’s a moving target. Computers are getting better, so prediction as a whole is a lot better than it used to be, but it still doesn’t handle things like local conditions very well. Georgia is affected by all these global weather patterns, but it also is affected by its own local terrain. The oceans that are close to us cause sea breezes along the coastal areas, the mountains are cooler and are more likely to get snow. They also direct cold air down the east side of the mountains.
Here in Athens, we get something we call “the wedge”, which is a really shallow layer of cold, dense air that comes down the east side of the mountains. It can’t go west because the mountains are in the way, so it comes down and hits the northeast part of the state. The official name of the phenomenon is cold air damming, but we usually call it the wedge. It comes in and it brings this gloomy weather that is cloudy and more likely to cause problems with ice storms because of that cold air, depending on how cold it is. We don’t know how that’s going to change. It’s going to continue because the mountains are going to still be there and the coasts are still going to be there, but the larger-scale weather patterns are going to change somewhat, and we don’t know how all that interaction is going to affect us here in Georgia.
We expect Georgia to get warmer. It’s getting warmer already and nighttime is getting warmer than daytime. That’s because of humidity, most likely. Urbanization probably has something to do with it, although a lot of our weather stations are in the country.
Right now, there are also cuts to observing systems like radiosondes, which sample the atmosphere vertically, due to staffing cuts in the National Weather Service. The loss of data makes the computer models less accurate and that makes it harder to make good weather forecasts.
