WxUSAF

And Ukie.

TJ Watt was reactivated by the Stillers. I mean, I’m glad he doesn’t have covid, but wouldn’t have minded another 2 days in testing ambiguity… Question now is where’s the O/U on his sack total for tomorrow? 3.5?

@MillvilleWx if we can’t get a good, old-fashioned cold shot with the source region that frigid, by mid January at the latest, then it might be time to quit winter in the Mid-Atlantic. I’m not even talking anything that dramatic. Like highs near freezing and lows in the low-mid 10s without snowcover and perfect radiational cooling conditions. Shouldn’t be as hard as it’s been for the last 2-3 years!!

Check the 3rd graphic in this tweet: composite 500mb height pattern for December MJO phase 7 in Nina’s. Quite a few similarities to the GEFS plot that @CAPEposted with -EPO, start of NAO ridging and gradient pattern over us.

Weren’t we supposed to get down into the 30s this morning? Only 44F at my house. Freaking DCA is colder than that.

Gradient pattern. Would not be surprising if the pattern evolves to that as it wouldn’t take major events like an SSW, etc. Gradient patterns can work but would favor points to our north. Good news is that Canada has plenty of cold air to work with.

Ukie is real live actual snowstorm. Just like JB promised!!

That’s odd since JB is touting his 95-96 analog so much!!

Shortwave is trending flatter which is good for us so it limits WAA ahead of it. GFS still hates it, but its moving flatter as well. Still doubt we thread that needle.

Mid-Atlantic Niña winter: now only 99% hopeless!

It’s almost all southern stream, which is much better for us. But the souther shortwave is also stronger, so more ridging and WAA ahead of it. That could work in Jan/Feb or with a good airmass but we just get fringed with the cold air from the earlier FROPA.

It’s close and would be a nice setup with a better airmass or later in the season. But this thing is going to bleed away from us. Just don’t see it happening.

This possible event has it all: Great Lakes Low? Check! Perfectly timed mediocre airmass? Check! Early December? Check!

Certainly very cold air in Canada with that look ^^^, so any digging shortwave or transient ridge out west should be able to tap into that.

The wave-3 pattern that’s setup is pretty stable, but you’re right that the long range guidance slowly evolves it extending those ridges more poleward, which pushes the PV farther south into Canada. That should squash the SE ridge and also push the storm track to a more favorable latitude. But it’s a way off and very subject to change.

GGEM and Euro both give us a little snow in a week from a low passing through the Lakes. Those always work out

Parrs Ridge itself

Dude, you’re living in the promised land now. There are no sucky winters anymore.

Despite how seemingly chilly it was, BWI was only -1.5F on the month. 14 days with freezing low temps, minimum of 27F. Compared to recent years number of days below freezing and min temp in November: 2020: 3/25 2019: 10/22 2018: 13/24 2017: 13/21 2016: 9/23 2015: 7/28 2014: 10/18 2013: 17/19 2012: 15/25 So you can see that 14 freezing days is quite respectable compared to the last decade, but a minimum of only 27F is weak sauce.

Low of 29 on the first day of winter

The advertised MJO pulse into phases 7-8 looks to largely peter out and just make it into Phase 7 at low amplitude. We had a weak strat vortex to start the season in October and early November, but it has quickly consolidated and there’s fairly weak poleward and upward wave forcing to disrupt it now and forecast. Combine that with the Niña/PDO base state and there’s not a lot available to dislodge cold out of NW Canada.

Well, model guidance has not been friendly of late. GEFS keeps bouncing around with the strength of the two primary NHEM ridges in the WPO domain and western Russia/Scandinavia. 12z has them fairly flat. That leads to a strong trop PV that is coupled to a strong strat PV…++AO. So we torch. No sign of JB’s promised snowstorms or big strat warming. I guess the Dec 6-10 window isn’t totally closed for something, but I wouldn’t bet on it. This looks like a shut the blinds situation for awhile I think, these sort of patterns take awhile to breakdown, particularly when it is supported by SST and subseasonal patterns like MJO.

And will again today

Didn’t notice before, but BWI recorded a T on Sunday.

Flurries in Greenbelt as I arrive at work