CAPE

Yeah March of 18 was a nice event here. If you look at the mean (without the anomalies) for the period leading up you can see more clearly there was a bit of a ridge out west though. PNA looks neutral/slightly positive.

The second wave is in alignment with what the ens means have been advertising as the initial chance for something other than rain for days now. This place would be a lot less bipolar if folks paid less attention/didn't react to every model cycle of the operational runs at long leads. eta- the ensembles will have some run-to- run variability, but it won't be the wild swings that we see with the higher res operational models. The basic idea is to use them as a tool to reduce the uncertainty in the long range for a given outcome at a specific time.

We are in the range now where the operational models are beginning to flash the potential for the period beginning early February that has been depicted on the ensembles for several days. Currently the means suggest the chances for frozen increase around Feb 2nd.

6z GFS has more confluence to our north with the timing of the NS shortwave, as a bit of energy ejects eastward out of the southwest. Brings a band of snow across the area.

The propensity for ridging to develop along the east coast even with a -NAO is problematic lately. TNH + Nina + warmer SSTs might be contributing to that recently. I still want to see what happens when we get a moderate Nino with legitimate blocking. In the past a significant number of our big snow events in a Nino have occurred when the PNA was 'unfavorable', but I am pretty sure recently (2009-10 and 2016) all the events had some semblance of a PNA ridge leading in. Ofc there is more of a tendency for a +PNA during a Nino historically. With -PNA seemingly more prevalent now overall, the -NAO/-PNA combo during a CP based Nino needs to be "tested" .

Yes and the GEPS does to a lesser degree too. Pretty nice look here on the EPS for the Feb 2 potential.

Nice signal for a wave moving along the boundary on all 3 global ens means, with cold coming in with/behind the predecessor wave.

But there were 3 waves, and you probably ended up with more snow than any of those areas. In most cases if you post an anomaly map like that for a given MA winter the NW areas will be closer to (or exceed) mean snowfall. More typical. It just didn't work out that way last winter, but many areas still got some snow despite being below average. I doubt that becomes the new bar for what is 'good' lol.

Of the big 3 global ensembles, the EPS overall has had the driest look with the cold in place.

Re: last winter. Jan into early Feb was a pretty cold period, and there were 3 all-snow events for eastern areas during January. Other areas in our region got in on at least one of those. The pattern was progressive, and favorable for late/offshore coastal development with legit cold air and the thermal boundary displaced eastward, but it wasn't just one lucky/fluky wave. For the region overall I suppose you can say it was god awful, but areas to the NW did at least okay in Feb and March iirc. It was the the in-between areas along I-95 that mostly missed out, and as you have said- that's pretty typical in a Nina. It's ultimately an IMBY deal, so yes I remember it as a pretty good winter even though Feb/March yielded nothing of significance. Could have easily ended up with 25-30".

He already informed me lol. Lets just get some snow up in here.

lol no. I know full well the reality but prefer to track the chances when they present themselves. I know what the odds are and the ways it can't work. No fun beating that dead horse.

Bad trends!!

Nah that was just for you.

Remember I claimed all storms in the Feb 1-8 window. Most y'all think its dead anyway lol.

Interesting look.

Not really seeing it outside of run to run noise. The window is still roughly the first 8-10 days of Feb. Better h5 look than 12z yesterday imo.

Some snow mainly for places just to our SE.

Low solar and many -NAO years that decade. I did a year by year analysis of the h5 composites and many of those winters were impressively cold in the midlatitudes- some Nina, some Nino, some Neutral. Some of those looks.. just hard to imagine seeing them today.

Didn't realize he was predicting a +PNA. That's a switch lol. But yeah we shall see if the hints on the latest guidance of a +PNA is a mirage. If that's real, the mid month period might be workable. Most extended products have the NAO trending towards neutral/negative just after mid month fwiw.

But it's been clear the rest of Jan was toast minus front end slop chances for the NW crew this week. You have been honking about Feb 4-7 for days now. Well yeah, that is still 10 days out. The ens means continue to advertise chances for early February.

I missed that one lol. If we have a ++NAO, that likely means there is a +AO, so that's not favorable for cold and snow chances here. There are exceptions, like a -EPO/+PNA driven pattern, which can bring the cold but frozen events tend to be light to moderate from weaker waves, and amped systems tend to track inland or cut west.

It's not complicated, so that's a plus. We always have the failure modes.

There is a neutral PNA look towards the end of the EPS and GEPS runs, with hints of it trending positive. GEFS suggestive of this too. Have to see how that plays out. Looks like the NPJ retracts a bit but haven't looked into it enough to get an idea if that is something of persistence going forward. It sure would help the mid month period.

Not much has changed on the means. The GEFS and GEPS hint at an initial wave on Feb 1, then another one right on its heels a day later with colder air involved. I didn't dig into the members so it could just be timing differences, but the upshot is there is a chance for some frozen as the cold arrives in the Feb 1-3 window. There are other chances beyond that with colder air in place. We begin to moderate around the 10th as the TPV lifts out and the NAO trends significantly positive.