Winter Pattern Taking Shape

Back in September, I strongly speculated on the possible winter pattern. This was my initial outlook given the initial conditions and projections FOR DECEMBER back in September.  In reality, the southern jet stream hadn't established itself as a winter storm driver.

The position of the warmth was too far west for December.  The arctic air over the North Pole was very stable. The ridge was powerful across the east. Heavy rain and severe storms/deadly tornadoes during the month were common around Christmas.

On December 6th, I opined using videos (bottom half of the post at this link) showing the stronger position and intensity of the southern jet stream in January.

Our final winter outlook in late October echoed this southern panhandle storm track for the second half of winter

The extended models are this southern storm track (panhandle lows) as the dominant track through much of February.  Here are the snapshots on six periods of seven days each ending during the third week of February.

Most of the teleconnections (NAO, AO and PNA--EPO bouncing back a bit) showing troughiness in the east overall.

All of these factors seem to be the real deal which will lead to colder temperatures and higher chances of panhandle low type systems to interact with colder air leading to an eastward push of snow!

Lake Erie ice cover is nearly non-existent. Last year (before the record setting cold developed) ice cover was only 5% through the first 8 days of January. The current water temperature is still at 40 degrees.  The average water temperature is 35 on the 8th. Any cold outbreak like what we will see next week will aid in dropping the water temperature versus adding lake ice outside of the western basin where the water depth is shallow. Bottom line, lake effect snow is more possible January through March than in past years.

Warmth Continues...When Will It Flip To Winter?

No one is complaining about the above normal temperatures after the two past harsh winters. Above normal temperatures across the eastern 1/2 of the US.  This warmth is not unexpected given the strong El Nino reaching peak strength though I am somewhat surprised that the warmth has been this consistent.

It can't last forever.  So when will it flip or at least trend colder with higher chances of snow!

Remember our preliminary December outlook issued back in early September showed the core of the high pressure/warmth across the northern states into Canada with the core of the low pressure centers across the south (panhandle low type systems).

Through the first week or so, the core of each HIGH and LOW is much stronger than anticipated yet they are roughly in the same position as our forecast 3 months ago indicated. However, the southern lows (Panhandle type) are far weaker and, as of this writing--December 8th--are just now showing signs of developing. (see the smaller "Ls").

Since November, the warmth has been extensive with below normal temperatures in the west. Warmer colors indicate above normal temperatures, cooler colors below normal temperatures.

Some computer model projections have been bullish in tracking these southern lows further east and the warm ridge further north into Canada by the beginning of Christmas week.

The big questions for the end of the month and Christmas week: 1) How fast will the ridge lift north and 2) how strong will the low in the southwest/panhandle region push east?

We do know this: Any easterly migration of the southwest low along the southern jet stream will increase our chances of a wet panhandle-type snow by month's end. 

The chances we will receive wet snow from a panhandle low will climb further after the first of the year.