BAD SLEDDING FOR SANTA...
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ALL I WANT FOR CHRISTMAS....
One of the few things I really want for Christmas is a nice powdery snow. Unfortunately for me, that's one thing I'm confident I won't be getting in my stocking this year. Nowhere is that in the cards with less than 5 days until the big man arrives. In fact, if anything the area is setting up for another big warm-up that will seal my fate in that regard. Look what the GFS is showing for highs Christmas Eve day. I hear the reindeer are being equipped with special air conditioned back packs so they won't overheat.
Highs in NW Texas and much of Oklahoma are in the range of 80-85 with a 70 possible up to St Louis. That kind of warmth is pretty much off the charts, especially during the shortest days of the year! It results in departures that are nearing 40 degrees above average in the southern Plains. Up this way, we should be 15 to 25 degrees above normal.
Here's the upper air pattern that's driving the warmth at 500mb. Cold air is plunging into the west while unseasonal warmth surges into the central U.S. ahead of it.
The EURO meteogram in the Quad Cities shows a high Christmas Eve day of 57 in the Quad Cities. That's a good ways away from the record which is 65 set in 1889.
However, a 57 is just 3 degrees from 60 and as you can see below highs in the 60s have only occurred twice in about 150 years of records on December 24th. (1.4 percent of the time). Only 7.5 percent of those years have we been in the 50s. If we can make it to 57, we would be in the top 4 percent of our warmest Christmas Eve days. If it's not going to snow, it might as well be warm!
What's disappointing to me is that we are just now getting into phase 7 of the MJO which is a cold phase in December. So we should get a quick shot of cold after Christmas but soon after it's January and the MJO on the EURO is shown only inching its way through phase 7, hardly budging December 27- January 3rd. See how phase 7 goes from being cold in November and December to being a warmer phase in January. Anyway, if that western trough holds well into January that will make it very difficult for any cold air to hit and hold in the central Midwest.
And when I say cold out west I mean it. These are the temperature departures December 26th on the EURO control and SW Canada is flat out frigid with readings as much as 52.9 degrees below normal.
If that cold air ever breaks free in mid-January look out. Typically, at this time of year a cold air mass like that finds a way to make inroads into the central Midwest due to its shear density. That cold air wants to push. What seems to be messing things up is the PNA. It's in a very negative state and projected to literally reach the bottom of its range 5 to 6 standard deviations below the neutral base state around December 27-29th.
That's what's known as a negative PNA. The extreme strength of it is off-setting the cold air and holding it a bay. You can see the different impacts brought on by the negative vs positive phase below.
Just look at how closely the predicted 500mb jet stream mirrors the graphic. That is a classic -PNA. Right now that is saving us from winters wrath.