OceanStWx

The EFI looks at the 5 week window centered on the forecast period and compares model climate to ensemble distribution. The more ensembles higher or lower than the m-climate the higher or lower EFI will be. Irrespective of sign, EFI closer to 1 is more unusual. Shift of tails looks at the top 10% of ensemble members. The more extreme those members, the higher the shift of tails will be. That can clue you in to just how big the potential is with certain events.

The Euro EFI stuff can help with that too. The shift of tails shows you what the outliers at the top end are saying, but the shading tells you where the meat of the ensemble is.

Right on time to set everyone's expectations unreasonably high.

But how much snow?

DESI tossing out 4 clusters, but there are two dominant ones accounting for 64% of ensemble members. More or less varying degrees of amplification. But the snowier solutions are more amplified trof. The more you lower heights locally, he snowier the outcomes. Which is a pretty wild difference when you think about it. Some clusters feature a ridge overhead 08.00z, vs other clusters featuring a trof. So nothing is locked.

Just some ?

High stakes. Can't wait for Dendrite to steal all the snow.

Compare BOS to MSP for the upcoming stretch. You can see at least three windows at BOS where QPF is clustered closer in timing (that signal at 300+ hours is actually pretty strong given the natural increasing uncertainty at that forecast range). If you squint at MSP you can see maybe one window of tighter clustering in time. You can also see the whiff potential in the BOS plot. Those gaps of no QPF in the first window show members that are fish storms. Of course this is just QPF, so a cutter can still have a great signal but a poor result for the weenies.

I would actually say the signal may be even stronger for 1/10. Ensembles for BOS are pretty tight clustering in timing for 1/7 and 1/10, lesser so for the next one after that. But it's definitely a strong QPF signal for an active stretch. Usually those 24 hr QPF meteograms look like a shotgun spray, but these all have well defined windows for QPF, which is a higher confidence signal.

"may be" "could" "assuming enough" La la lock it in...

Yeah, the tide was a couple hours earlier down there and overlapped the winds better. 4-5 ft surge is impressive.

We actually ended up not even flooding at PWM. A few vulnerable coastal spots did, but otherwise it was NBD on the coastal flooding up here. So if anything we hyped that too much. I think the timing of the tide and worst winds didn't overlap like forecasts showed 24 hours earlier. This was my Sunday evening update that expanded the high wind warning. I'm not upset with it at all. 50 mph all the way to Sugarloaf? That's going to do some damage.

You're proving my point. This isn't widespread. Criehaven is a rock in the middle of the Gulf of Maine. It was a good wind event and high impact, but I don't believe the impacts came from the magnitude of the wind gusts. I think it was the duration of the wind gusts and antecedent conditions that made this one of the record books.

I think it was a pretty normal wind event from a magnitude perspective, which is how the utilities prepare. Everything is based on wind speeds and time of year (relative to leaves). The high impacts I think came from a longer duration 50+ mph from a classically damaging direction and over a large area. In your dreams? I just don't see evidence that 60+ was that widespread. But the inland penetration of 50+ mph winds was pretty expansive.

I think that's just CMP.

This has been a great December so far. Spotters calling in with 3, 4, 5 inches and I don't know if they mean rain or snow.

It's funny, our list of CWOP sites that report good wind don't have many big gusts. Only 13 with gusts above 58 mph, and one of those was MWN.

I mean mesos were spitting out quite a large area of 60 kt gusts, which definitely didn't happen. But like Ryan said, it was a pretty solid signal for an extended period of 50 kt possible.

I think another factor has been the duration of winds. We're usually a 3 hour window of the LLJ, but this event started at like 9 am for PWM and they were still gusting over 35 kt last hour. That's a long time to beat on infrastructure. Even if models like the HRRR and RAP tend to mix too deeply, there was a good signal for a long duration wind event greater than advisory thresholds.

Sounds like an absolute disaster around Sunday River. Bunch of water rescues going on. If I had to guess, people are trying to bail on their vacations but are running into high water and washouts everywhere.

Some of the towers have wind thresholds and they have to evacuate (PWM nearly did today).

Nope, and the ASOS line is busy. So we may never recover that.

CMP saying my power is back on, which it definitely isn't. But at least they are cutting rates next year?

Actually Oct 2017 was tops, I think we pushed 500,000. 1998 was around 300,000.

They gusted to 54 kt, which is the highest since 1995. That place is sited in a pit and has never gusted above 50 kt until today.