Weekend warmth comes to an end Monday; seasonably cool conditions return

After spending a week dealing with extreme cold, Saturday afternoon’s high temperatures were a pleasant change!

We expect another repeat for Sunday afternoon, but after that, the seasonably cold conditions return.

What’s causing atmospheric “thermostat tango”?

Our weather patterns at the surface are dominated by the jet stream, which is a ribbon of fast-moving air that encircles the globe in the mid-latitudes about 5 to 7 miles above the ground.

This winter, large buckles — or “troughs” — in the jet stream have allowed bitterly cold air to surge south from the Arctic to the Tennessee Valley. The past week, a relatively large “trough” continued to impact the Southeast, but it finally relented and a “ridge” developed over the weekend (ridges usually result in dry and warm conditions).

With that said, the ridge will eventually give way on Monday, and another “trough” will come swinging through the Southeast once again. This particular trough won’t be as deep nor as strong compared to what we experienced over the past two weeks, but it will be enough to drop daytime highs into the upper 40s to low 50s, and overnight lows back into the low 30s — typical values for late January.