Blocking of the jet stream related to Sudden Stratospheric Warming event and -AO/NAO underway

First major impacts felt in Japan, Russia, China, Asia, Europe

Major long-lasting record cold coming to Georgia soon? NOPE.

There are just hints from modeling and signals, but not just cold signals, a danger (if you love snow) for warmth to come exists as well.

I don’t worship models and waste my time with what they show beyond 192 hours for specifics, I only look for signs. Whoever wants to do the other can but leave me out of it. If I have something to say I’ll do a tweet and/or blog about it. Otherwise don’t ask, I am not in the speculating business nor the entertainment/tantalization business.

We do have the most negative Arctic Oscillation in a decade or so which is noteworthy. It is ONE important aid in cold waves for North America but just one.

I’ve been talking about the POTENTIAL for a major change to more wintery weather East of the Mississippi River in the long-range for the second half of Jan into Feb thanks to developments at high latitudes than can block the jet stream Southward since mid-December. I explained that not all SSW events are the same and that sometimes the big cold goes into other parts of the world, sometimes into the Lower 48, sometimes all regions but that it can take up to 5 weeks. I also explained how any snow usually happens FIRST to the North and West of Georgia before we can get some chance later. I am not going to waste your time or mine by repeating myself every day or every week.

Well, if you’ve been following the news there has been record cold and or snow the past week or so in Japan, Russia, China, Asia and now parts of Europe. And yesterday and this morning snow amounts in TX not seen since the early/mid 1960s and significant snow in LA/MS NW AL:

Parts of TX/LA/OK/Ozarks have now had more snow than some areas up North that are normally snowy. Very aberrant for a La Nina winter. This is consistent with the past decade or so where El Nino and La Nina winter weather behavior has been abnormal, reflecting the climate shift where the underlying Earth-Sun-Ocean-Atmosphere-Stratosphere system base state has changed. This makes using past weather history to predict future weather more unreliable.

ONWARD!

The Pacific Ocean continues to be loaded with systems and we continue to see the unusually active sub-tropical jet stream (STJ) pattern usually seen in an El Nino winter NOT a La Nina winter as well as split-jet streams in the sub-polar jet stream.

MOST of the favorable for snow and cold in the East and SE blocking patterns have become established but not all of them. The North Pacific pattern is so far still not cooperating with the other signals, same with the South Pacific (MJO) which is indeterminate so far, so the wait goes on.

It will probably take another big storm in the Midwest or Northeast to help drain more cold air down into the lower 48, that process could start happening this weekend and again at the end of this month into February as the split jet streams sync up or merge (phase).

So as previously stated in a handful of blogs already, the door is ajar-the window of opportunity is opening, but not clear anything will come through.

However, if the high latitude blocking lasts for many weeks thanks to the SSW, AND we get a better North Pacific pattern (-WPO/EPO and +PNA) with high pressure ridging in the Yukon and Alaska THEN we could see lasting and impressive arctic air intrusions into a good chunk of the U.S. East of the Rockies with the SE sharing in at least some of it.

On the other hand, IF the -NAO/Greenland block breaks down to neutral or turns positive BEFORE that can happen then the dreaded (for snow lovers) Southeast ridge would build and warmer than normal temps would take over in our region of the country. Often when the pendulum swings from cool spells to warm-- it’s extreme.

For the next week and a half or so the active wintry weather for the eastern U.S. will be North of Georgia. Still not looking at any sort of MAJOR PROLONGED cold yet.

Models will continue to struggle and fluctuate more than usual due to the volatile nature of the ongoing SSWE!

For daily weather info follow me on Twitter @MellishMeterWSB.


Kirk Mellish

Meteorologist

mobile apps

Everything you love about wsbradio.com and more! Tap on any of the buttons below to download our app.

amazon alexa

Enable our Skill today to listen live at home on your Alexa Devices!