OceanStWx

Euro may be a little too flat on this run based on observed heights around the shortwave, but overall my concerns are still tied to the RH in the DGZ. Not as solid as I would like to see for a widespread advisory event.

Ascent so often in the cool season is sloped ascent too. So the rising air at 850 mb doesn't go straight up, it slopes towards the colder air (i.e. north) and continues rising through 700 mb. That's a signal for widespread, broadbrushed snow. When you start stacking 700 mb lifts on top of 850 mb lift, that's when you get concentrated bands of heavy snow.

College of DuPage has the dynamic tropopause for the GFS, and Alicia Bentley has some good stuff on her UAlbany webpage. Pretty sure Tidbits does some now too. Yes The PV anomaly has a cyclonic circulation around it, which can contribute to vorticity at 500 mb (but that's just one level which is the problem if the shortwave is located higher up in the atmosphere). The circulation that develops at the surface as a result can then result in low level PV generation once WAA gets going (diabatic heat release (convection) is the most common way). This then induces enhanced circulation aloft, and so on. Kind of like constructive interference where the lower and upper levels continue to feed off one another.

I find that it can highlight the more subtle waves better than traditional vorticity maps can. Especially warm season stuff.

Different PV. This is not the polar vortex, but potential vorticity. High potential voriticity induces cyclonic flow in the low levels, so can enhance low pressure systems. High potential vorticity is also typically associated with stratospheric air, so when people talk about trop folds these are big potential vorticity anomlies in the upper to mid levels of the atmosphere.

Looks like we're in for some wild swings. PV streamer drifting across the country and it all depends on how the northern stream captures it. Could be a cutoff for Florida or Nova Scotia.

Delivery angle will help too. Not quite shot from James Bay, but definitely much better than via the Dakotas.

The block will matter more late in the game, right now the uncertainty is in the shortwave coming onshore out west tonight. 00z run should've had a decent sample on it.

Yeah this suite got colder, but the shortwave isn't onshore until tonight and I'm not going to bank on this being a long term trend until we sample that with some balloons.

There is definitely some thump potential. Definite mid level warmth worries down in SNE, as the thump may already be too warm. Overall if we don't cool the column a bit even CNE and NNE run the risk of a very elevated DGZ and saturation issues. F-gen looks nice though.

Hayden's on it, high wind warnings for the Cape and Islands.

I get it. I don't want to be working this Friday night either...

I'm a little surprised by that. We issued an advisory with the 10 AM update, so it's not like there wasn't time to get out there and pre-treat or even get ready to treat.

Is it possible the Cape is in for a big blow this afternoon? Seems like a pretty meh advisory for 50-55 knots 500 ft off the deck at CHH. There's a nice surge from the warm front this afternoon too. I think I'm taking the over on 55 mph wind gusts for the Cape/Islands.

You know it must be a good December if we're talking about EMLs Functionally I don't think there is any difference between the source region. What there has been some research into is the role aerosols play in worsening tornado outbreaks (hypothesis is that adding aerosols warms the lower levels, lowers LCLs, and increases wind shear). It's definitely an emerging area of research, but I think the Mexican aspect loops in because EMLs originating in that area tend of have more aerosols from Central American slash and burn operations.

I have two within 15 minutes of home! Does nothing for my putting game, but just to swing the club 1000 times over a winter is enough to keep my from losing muscle memory I hope. My biggest issue last year was not giving my partner enough of a hanidcap. He was a beginner and played like a 40-50 handicap easily. We gave him a 25

Nothing like getting sea sick with your feet up on the coffee table.

I like a nice sand lined course, it looks sharper to my eye than rough lined. That's not to say I play any better on them. Speaking of my play, I'll be in the simulator league again this winter. We'll see if that gives me a jump start on the spring swing.

FWIW, coop average depth is just add up all the daily depth reports and divide by the number of days in the month.

Yes, that's the current regional criteria.

You get some leeway with criteria (theirs is 3") if you want to say impacts will be a problem. They can claim the commute will make 1 or 2 inches problematic and thus issue an advisory for it.

Reaching?

I always sign my last name, Legro. I still think someone in SNE could pull off a 3-4" report, but the question is how do you want to message it. Do you prefer to paint a narrow band and potentially put it in the wrong spot? Or would you rather broad brush 3-4" everywhere and know some of that will be wrong?

Oof, on the HRRRX reflectivity product you can see clouds streets showing up in the Gulf of Maine starting around 08z tonight. Not great if you're looking for snow on land up in NNE.

The tough part is that 850 mb f-gen is well east of the 700 mb forcing. i.e. way too sloped to really help enhance omega for warning criteria amounts.