Looking at the 850s

For today's excellent adventure, we will simply look at the the 850 mb level of the atmosphere in terms of the temperatures over the next 10 days. It behooves one to look at the atmosphere one mile above earth's surface as the effects of friction and other surface interactions are minimized in order to see how the atmosphere is cycling.  Let's start with the 850 mb temperature initialization for the Euro from last evening...

Generally mundane cold across the eastern CONUS (Continental United States)...quite typical for this time of year.  There are a few pools of colder air in the sea of mundane cold; namely by Lake Winnipeg and north central PA, i.e. "God's Country"!  You'll also note a few patches of above freezing air in Quebec.  Now look at how that evolves by Monday evening...

A general moderation in the temps due to zonal flow across the CONUS.  That is not a very cold map for late December!  But a careful eye will note in the very NW corner of the map, some colder air lurks.  24 hours later, voila...

An energetic diving jet drives the sub-freezing air all the way into central TX.  On the east side of the trough, warm air is forced northward into New England and all of the way into Ontario and Quebec.  This upper air configuration should allow surface temps to approach 60°F for Christmas Eve!  Santa will only need his union suit when visiting the sub-tropics of KMDT this Christmas!  Then by Christmas Day, the trough tilts negatively and will spin up quite a storm that will deepen over the Great Lakes.  For us, it means a rainy and mild Christmas Eve followed by a vigorous frontal passage bringing a gusty Christmas afternoon with temps falling back to December-like levels...

Look at that 20°C air streaming up from the tropics towards Cape Hatteras!  The atmosphere is in quite a tumult this Christmas...but it returns to normal for a day with WNW flow for Christmas Day.

But that poleward bulge over IL will be over the northeast one day later with a return to milder air, but not as warm as Christmas Eve. If we can get any sun...and we should...we will see temps in the mid 50s for Friday...

The cold front will traverse the state Saturday and usher in much colder air as we anticipate the coming of 2015...

...and by the end of the 10 days the Euro runs, cold looks to be the rule across the most of the US with what appears to be a steady stream of cold air plunging from the arctic into the CONUS...and likely to continue well into January...

Now I know we don't live at 850 mb, although I've met a few people in my life that thought they did!  But as I mentioned earlier, it gives a good feel as to what the air wants to do and how the various air masses will move.  Hence, an idea of the getting a good feel for the sensible surface weather can be attained...I hope that makes sense to y'all.

As usual, I'll leave you with a little musical wish...

Enjoy your week's end and your Christmas week!

Thanks for reading!

Smitty

AA:  Monitoring the air flow a mile up to see the cold moderate to a very mild Christmas Eve.  Then one blustery colder Christmas Day followed by another couple of milder days.  Then the bottom drops out early next week!  Merry Christmas my friend!