The incoming cold snap would be noteworthy in the dead of winter, so this polar plunge is remarkable for this early in the season.
It is hardly unprecedented though so nothing we can’t handle. It is a fairly quick hit and run, in and out.
We probably will not break any records locally, but places not far away probably will and lots of records will probably fall in the Midwest, Great Plains and Northeast states. But records will be possible all the way to the Gulf Coast West of here.
Since this is dead of winter type polar air WINTERIZE YOUR HOME AND CAR/TRUCK. Turn-off water to the outside of the house and shut down decorative fountains.
Temperatures will fall hard and fast after the cold front passes through bringing a decent shot of rain to much of Georgia late tonight into tomorrow morning before the temperature drop. Some brief sleet or snow possible mainly in the Georgia mountains early Tuesday.
I’ve been warning you about this pattern change in blogs and on Twitter Since November 4th:
It’s not just the actual air temperatures that are impressive but also the geographic coverage of the arctic air mass with only the far West and South Florida spared.
We’re keeping an eye on the tropospheric patterns that can lead to more polar vortex splits and sudden stratospheric warming events in the months ahead that can lead to more cold air invasions after a warm-up.
A couple snow periods will come with it for the Midwest, New England and maybe even parts of the Mid-Atlantic states with flurries possible in the Southern Appalachian Mountains (not Atlanta), an inch or more of snow in parts of Tennessee and snow flakes should be seen “in the air” in areas adjacent to TN as well and as far South as Northern Louisiana.
For some areas of the country it could end up being one of the coldest ever November air masses this early in the month. And America will not be alone as much of Asia and parts of Europe will share it.
In ATLANTA during peak winter our normal high temperatures are in the 50s so this will be cold for any time of year with highs and lows below-normal and our first hard freeze coming early in many locales as the first official lows of 28 or lower is on average December 5th, a couple weeks earlier for the North suburbs.
This may naturally have you wondering if this means a cold December? Does this mean a cold winter?
Short answer no, at least not necessarily by any means.
Research has shown there is SOME persistence of weather patterns from Fall to Winter and from November to December, but certainly not all the time.
I mentioned an early cold wave is not unprecedented.
Five years ago a similar big Southbound dip in the jet stream brought a big November chill:
But December of that year very warm most of the country:
What about last year? Did you already forget last November was colder than average?! Top 10 cold in many states just to our West and North.
But the December that followed? Warm again.
In the past similar ENSO conditions/sea-surface temperature patterns in the Pacific with similar October weather as we have this year (left panels below) have lead to above-normal temperatures for much of the nation in October with cold out West like this year (right panels below):
See the Decembers that followed like conditions in the past:
Even without an official El Nino an El Nino-like base state of the background atmosphere response has revealed a tendency in the modern era where even in winters that end up being cold that December is biased above-normal and we’ve seen this in 2014, 2015, 2018. The 15-year or so trend has been for mild canonical El Nino Decembers.
So a betting man would say the odds favor a mild spell to return late November and/or in December after the coming cold.
This does not mean December HAS to be warm, as some of the past similar El Nino-like Decembers have featured below-normal temperatures and a couple were quite cold in much of the nation like 1968 and 2009.
That’s the thing about weather: it does not work in a straight line but rather is chaotic which is why predictions are hard.
Here is the correlation between November and Winter:
So there is NOT much signal from cold in November in Atlanta and a cold winter to follow, the signal is weakly positive especially if late November is cold not early November.
Dr. Joe D’Aleo did research on what type ENSO patterns had the most month to month volatility and variability this winter looks to be active and changeable (on the higher end of the range this year but NOT quite the highest):
It’s way to early for a specific Thanksgiving forecast obviously, so here are some interesting notes:
How November plays out and new data not yet in for October may tip the forecast for winter one way or another. I’ll update it as needed by the start of December at the latest.
For more follow me on Twitter @MellishMeterWSB.