WxUSAF

HM citing the upcoming evolution reminding him of Jan 1987, which suffice it to say, is an analog that few here would complain about.

End of the run gfs eye candy notwithstanding, that’s a meager snowfall map east of the Rockies for the last 10 days of December.

Do it

@tombo82685 posted this elsewhere, but the ensemble means over the next 2 weeks are a reasonable match to Nino MJO composites in phase 6 in December and then phase 6 and 7 in January. Phase 7 in January is a pretty canonical Nino pattern in many ways.

I would cut the cord except for orioles. No streaming options.

Now here we go

Oh Jesus we’re relying on JB tweets for hope

I’m nowhere near tossing the season, but that’s a rough look and could put us out until Jan 10-15 or later if it verifies that way. Since GEFS rapidly flipped to bad, guess we hope it flips to something better again in the next few days.

GEFS is a toaster bath

The issue is the TPV is not dropping down toward Hudson Bay anymore on the GEFS. Instead it stays strong and moves up over the pole. If it’s going that way, I’d rather it go park itself in Mongolia than hang over the pole.

Huh?? 6z? Looks pretty rough to me.

Healthy looking snow squall near the m/d line. Heads up @mappy @psuhoffman @losetoa6 @HighStakes

Agreed. That’s pretty tasty as is and a tick or two away from top tier longwave pattern for mid Atlantic snowstorms.

Wife reports flurries in Columbia a little while ago

As I recall, Boxing Day storm had some warnings of a fail ahead of time. Was kind of on/off the model progs, we were always kind of on the edge, Miller B risk, etc. March 2013 was just a complete out of nowhere gut punch. I’ll never forget going to bed with this wall of snow approaching on radar, people on here in central VA seeing heavy snow and already exceeding forecast amounts. I told my wife I thought we’d get more than expected. Then I woke up the next morning and it looked like Monday morning with like 1” of slush and I just was dumbfounded.

HMs take on this discussion

@tombo82685, yeah will be interesting to see how things look in 48-72 hours. GEFS starts moving the TPV south on the 28th, and not coincidently, that's when the EPO ridge goes up. That's the mark on the wall. 6z GEFS actually accelerated things a bit relative to the last few runs previously.

Trend for strong southern stream shortwaves rolling across the country the last 2 months is clear. Have to think odds of a widespread big dog storm is higher than normal when you add in the trend of HL blocking. Still maybe less than 50-50 odds, but still above normal.

Bob, I agree that I think we'll get there eventually. Whether it's on Dec 29 like the GEFS thinks, some compromise of Jan 3rd-ish, or probably Jan 7 or after as EPS might suggest (via extrapolation), I don't know. I'd probably chicken out and lean toward a compromise of the first few days of January if I had to pick. One thing I came across in reading this morning is that there's a pretty huge snow cover deficit in Eastern Europe and western Russia. Always a bit of chicken-and-the-egg situation, but that might help bolster the Scandanavian ridging that keeps reloading the east -NAO and occasionally west -NAO and can be seen clearly on your CFS map above.

GEFS and Eps diverge significantly after D10 as has been said, but they’re very similar at D10. One subtle difference between them at D10 is the one that loads a good pattern for us on the GEFS and bad on the Eps. On the Eps at D10, the TPV is stronger and slightly more NW (poleward) relative to the GEFS. GEFS has the TPV a bit weaker and then moves it southward over Hudson Bay after D10. Eps keeps it at high latitudes and leaning toward Alaska. The tropical forcing and the wave 2 hit on the strat vortex peaking around Xmas suggest an evolution like to GEFS should happen eventually, but wouldn’t be surprised if it’s after the new year and not a few days before like the GEFS has.

Based on the forecast I’d wager we end the month +1-2F. Depends how many torch days we get. What’s indisputable is that our warm days are almost always warmer than the cold days are cold .

Yes. Think it happened early this year.

I can’t get plots for this while I’m on my phone, so it’s just memory, but I think GEFS picked up the early Novie EPO period and the secondary one in late Nov/early Dec earlier than Eps.

BWIs new asphalt tarmac certainly seems to be having an influence.

^thats certainly been true for the EPS in the last 8 weeks. GEFS has sniffed it out from range more accurately it seems. GEFS can rush it though.