Terpeast

Closing the book on November and now enjoying the chilly temps. 37 degrees outside, feels like holidays inside.

The hope is the weaker PV and -QBO tips us more into -AO territory for late dec through Jan. That’s when we should get our chances.

He likes to attribute it to CC and west pacific warm pool and the pac jet being too strong, but while those things aren’t wrong, I attribute it to something much simpler - there is no blocking and no 50/50 low. Get those two in place, that high is staying put.

EPS has it too for next weekend… and an even stronger signal for 12/10. Not often I see something like this more than 10 days out:

It still has something for next weekend. Low coming from the gulf moving NE. Unfor it has the same flaw as the tuesday system, high sliding off the coast too quickly

I think you're good for an inch+

2-4” dc metro (mean)

Looks like models have finally converged on a most likely outcome. A weak strung out wave with marginal in-situ cold air mass for I-95 west. East of the fall line can expect all rain, maybe a bit of sleet at onset. West of I-95 to rt 15 south of I-70, perhaps a coating to an inch with some mix before changing over to rain. West of 15 and north of 70 are in a good spot for 2-3” maybe even more at the higher elevations. PSU, mitchnick, and TSSN should be excited for this one. Maybe Weather Will and clskinsfan sees a couple of inches. Now for the most important question… Will I eat my shoe? Appears unlikely, but the “shoetastic” dish is definitely not off the table yet.

Not enough of a pressure gradient to drive cold air down back south

Interesting it shows an AK vortex but still ridging over the west coast. Probably because it is pos tilted. Orientation matters.

Overall idea hasn’t changed much, but we may get “luckier” with snowfall amounts.

And the SPV will weaken again in mid late dec - might be helpful for early mid Jan too

PSU will be happy too

Back edge upon me, hasn’t flipped from ra/ip mix. But was still fun. Onto the next!

GEFS did well a month ago when the MJO was still in 6. But EPS is now catching up in forecast performance since we went into 7. And don’t sleep on the AIFS ensembles for mid-latitude 500mb at 6-15 days out. It’s been wiping the floor lately.

Hard to believe it’s not even december yet. Feels good to have frozen and be tracking multiple threats. Sleet continues, 33.8

Temp getting interesting. 33.6 and dropping, dewpoint 29. Might end as snow before precip moves out? (Ashburn VA)

Didnt see anything faling, but deck shows that it had snowed and sleeted. Calling it a trace. Edit: still sleeting

If you compare the 500mb maps they aren’t all that different. The block west of alaska on aifs ens is further west on eps, but eps shows more western US ridging. Both show a TPV in canada with a eastern trough and a -NAO. Biggest thing is how the Alaska domain is resolved, as that will have big effects downstream.

Euro/eps doing best with general pattern, but not sure about thermals. Could turn out to be flatter/weaker but warmer like gfs/nam.

I think euro is the only model showing such a depiction. Either it will cave, or all the other models will cave to the euro. I think we will know with tonight’s 00z runs.

Fwiw both aifs ensembles and EPS have been cleaning up with verification scores at 500mb over CONUS. Other models aren’t even coming close.

Euro gives me a 6 hour thump before flip. If it’s correct, maybe my shoe will be on the menu……

The mid month warm up was to be expected. However the +epo is projected to wane at the end of the 15 day forecast period.

I think those who were saying less amp called it, and gfs took a step in that direction. Not saying its gonna snow, its too warm for the lowlands. Still thinking coating to 2” slop far NW of fall line.