WxUSAF

ALEET ALEET Digital Blue Fix at 12z ALEET ALEET

D12-15 on the 6z GEFS = wooo baby

Maybe a squirrel is farting on my PWS, but it has not gotten as cold as nearby stations the last couple days. 34F now verbatim while my neighbor is 30 and BWI is in the 20s.

Ok soccer fans…what does a draw mean for their chances here? Assuming a win against Iran and loss against England, it may come down to goals for/against?

Hi Chuck

Yup! And IAD had 3 days +20 or more!

Temp departures from normal yesterday: BWI: -15.4 IAD: -12.6 DCA: -12.8 RIC: -11.6

^straight up RELOADED there! That’s a nice look. Hope that holds more or less.

20.5 for the low so far IMBY. BWI and IAD have both gotten at least to 19, so ok @CAPE, that’s a solid November low temp.

Dropping like a rock now. 24.8F on my PWS

Record low max of 38F tied at BWI

Sharp defense, but offense was flat and sloppy.

To emphasize how subtle differences in the Siberian/Arctic PV could change how the RELAX looks, check the 12z vs 6z GEFS. 12z: farther south in Siberia and less organized. -NAO looks worse actually relative to 6z, but without a pig PV setting up north of AK, we’re actually able to get some BN temps verbatim. 6z: -NAO looking nice with ridging into Greenland and Davis straights, but the PV is stronger and more consolidated, driving a -PNA and floods the conus with PAC air. Given that, I wouldn’t put much stock in anything after the 28th or so. @CoastalWx mentioned this could be due to weak tropical forcing and hence the models bouncing around a lot. Makes sense, but with that PV, it could bounce between torch ahead of a cutter, but then a good cold push behind it with a transient -EPO.

Racking up our cold wind seasonal totals already!!

I raked yesterday. With this wind, you probably won’t notice by noon today.

I liked last winter having a January that felt like January. As long as Xmas week isn’t a flamethrower torch, I can gut through another disappointing December. But I’m cautiously hopeful it has some wintry appeal.

Yesterdays GEFS extended

I’m keeping expectations in check. Last few days were fairly pathetic. Area wide. Expecting DCA will sneak down to 30 tonight!

Weak sauce low temps.

Near-record strong -EPO with most of Canada snow covered and we’re going to struggle to get 2 or 3 days with double digit negative departures out of it. Must be all JB’s underwater volcanoes

Repainted the snow board with semigloss to help reflect more sunlight. Just need to refill the liquid N2 tank and it will be ready for winter!

Gov. Hogan tweeting yesterdays Hrrr

Low of 28

Our slim odds of anything frozen from the Black Friday storm look slimmer now, so let’s check in on the RELAX and RELOAD. Going into the beginning of December, the most robust feature on the ensembles is broad ridging over Europe, Scandinavia, the eastern Arctic Ocean, and extending into Greenland. This -NAO has been pretty stable on the ensembles in the D10-15 period with most of the variation on how far west it extends (e.g. into Baffin Island or Hudson Bay). The other robust feature is the one I mentioned in my last long post: the trop PV over eastern Siberia. All the ensembles have it, but how it plays with the other trop PV closer to the pole seems unclear. What I was hoping for, the Siberian PV to move east to Kamchatka and force the -EPO doesn’t seem to want to happen. The interaction of the 2 PVs keeps the NPac ridge flat. But there are subtle differences between the 3 that change the pattern over the CONUS and maybe what comes after for the RELOAD. Start with the worst: GEPS. GEPS is Nina-tastic. Cold western Canada, -NAO, and SE ridge is very reminiscent of last December and is a classic Nina look. Not what we want to see. GEFS is somewhat intermediary, but also not a look I love. It seems to want to merge the two PVs, maybe toward AK, which is a torchy pattern for us. Don’t be deceived by the blue over us. That’s a little induced trough below the NAO ridge. Extended GEFS show it getting worse after this but then with a somewhat remarkable reversal to a workable pattern around D25-30. Maybe a reflection of tropical forcing? Dunno. EPS is the best look by far even though it’s not dramatically different than the above 2. It weakens the PV over the pole and also the Siberian PV. This weakens the WPO ridge but also the -PNA. The shorter wavelengths put the ridge over the SW CONUS. With the -NAO, that’s a pattern that would be workable with minimal changes, even in early December. This all has been pretty changeable so EPS could be trash and the GEFS looking nice by tomorrow, but this is where we are for now. Think we do relax for the first week of December at least, but TBD if it’s just seasonable (maybe even leaning a little BN) or a borderline torch. Seems like the PV strength and interactions will drive this. Then hopefully the MJO progression leads to another -EPO period while the -NAO is still kicking.

Got something falling here but just melted snow I think