Expect to hear the term polar vortex tossed around during the next couple of weeks. For certain, much colder air is coming. But for most of that time in Richmond, it will simply be cold and dry.

Thursday and Friday afternoons will remain in the lower 40s, then surges of Arctic air will repeatedly invade from the northwest over the next couple of weeks, making for the coldest period of the season. Prepare to be below normal averages well into middle January.

Starting this weekend, and likely through the following 10-14 days, afternoons will average in the 30s with lows in the mid teens to 20s. There are signs that the cold pattern eases by the weekend of January 18, but there is no indication of back-to-back afternoons returning to the 50s until then.

Why so cold for so long?

Air travels around the globe in waves, and just like ocean waves, there are occasionally waves that push very high and very low. And sometimes those waves get stuck.

Richmond, like most of the eastern U.S. in the coming two weeks, will be on the receiving end of an unusual, but not unprecedented, southward surge of these waves, allowing the Arctic air to rush in repeatedly.

That wave pattern appears to hold for 10-14 days starting this weekend, keeping temperatures below normal until the third week of January.

The coldest period appears to be toward the end of next week or the weekend of Jan 11, and that is one of two periods in the next two weeks to monitor for snow — enough snow to matter.

Snow stock is up

An especially weak disturbance may surprise us with a dusting Friday afternoon or Friday night, but the first chance of significant snow in Richmond this season comes between Sunday night and Monday night. As a storm pushes across the eastern United States during that time, it appears cold enough to support snow in Richmond.

However, the system in question is still over the north Pacific Ocean, and the data have not been especially consistent about where its center goes as it passes Virginia.

A little farther to the south of Richmond, we get plowable snow. Too far south, we get nothing.

A little farther to the north, we get mixed precipitation. Too far north, just sleet and rain.

With it still 4,000 miles away, knowing its precise location to within a few dozen miles five days from now is a bit much to ask. However, the data appear to be converging toward a southerly track sufficient to produce a generous coating of snow on Monday in Richmond. 

Plowable snow in Richmond is certainly possible between late Sunday and late Monday, so do not lock in on one forecast idea on Friday and check out for the weekend. Subtle changes in the storm track will have a huge impact on what we see on the ground.

The second system toward the end of next week has a boom or bust feel to it. It is even more nebulous because it is so far in advance, but the weather pattern strongly favors storm development near the central Gulf Coast before steering winds were to drive a potential storm in our direction.

While still too early for any details, at least the ingredients are on the table to make some snow in Richmond. Over the last two seasons, we have not been able to get the ingredients out of the freezer.

Warmest two years on record

In spite of the cold stretch at the start of December, Richmond is finishing its warmest year on record, topping the previous on record — which was 2023.

Temperature data will be collected from numerous sites across the world over the coming week, and after the data is analyzed, several professional scientific groups are expected to announce on January 10 that 2024 was the hottest year on record globally — mirroring the trend here in Richmond.

Ironically, that announcement will come in the middle of a prolonged cold spell in the most densely populated part of the country — those areas east of the Mississippi River.

But remember, weather over a couple of weeks is like one offensive series in a football game. Climate is the whole season. In Richmond, 2024 had 51 days at least 10 degrees warmer than normal. Conversely, there were only 14 days at least 10 degrees colder than normal. 

A 51-14 score in a football game would be a blowout, and that is the signal of the warming climate.

December in Richmond further illustrates the point. There were enough warm days that the average temperature for the entire month skewed a few tenths of a degree above normal. As a result, every month of 2024 was warmer than normal.

Looking back further, if you were in Richmond from the 1940s through the 1980s, you could depend on five or six December mornings below 20° each year. But over the last two decades, the average number of December mornings below 20° has plummeted to one.

As we will find out in January, cold does not go away in a warming climate, but it is not as intense as 40-80 years ago. 

But if you were not here, this coming cold spell is going to feel a lot colder.